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  1. Avian Influenza A (H5N1)

    Centers for Disease Control (CDC) Podcasts

    In this podcast, CDC's Dr. Tim Uyeki discusses H5N1, a subtype of influenza A virus. This highly pathogenic H5N1 virus doesn't usually infect people, although some rare infections with H5N1 viruses have occurred in humans. We need to use a comprehensive strategy to prevent the spread of H5N1 virus among birds, including having human health and animal health work closely together.

  2. Avian Influenza A (H5N1)

    Centers for Disease Control (CDC) Podcasts

    2009-05-27

    In this podcast, CDC's Dr. Tim Uyeki discusses H5N1, a subtype of influenza A virus. This highly pathogenic H5N1 virus doesn't usually infect people, although some rare infections with H5N1 viruses have occurred in humans. We need to use a comprehensive strategy to prevent the spread of H5N1 virus among birds, including having human health and animal health work closely together.  Created: 5/27/2009 by Emerging Infectious Diseases.   Date Released: 5/27/2009.

  3. Sensitization with vaccinia virus encoding H5N1 hemagglutinin restores immune potential against H5N1 influenza virus.

    Science.gov (United States)

    Yasui, Fumihiko; Itoh, Yasushi; Ikejiri, Ai; Kitabatake, Masahiro; Sakaguchi, Nobuo; Munekata, Keisuke; Shichinohe, Shintaro; Hayashi, Yukiko; Ishigaki, Hirohito; Nakayama, Misako; Sakoda, Yoshihiro; Kida, Hiroshi; Ogasawara, Kazumasa; Kohara, Michinori

    2016-11-28

    H5N1 highly pathogenic avian influenza (H5N1 HPAI) virus causes elevated mortality compared with seasonal influenza viruses like H1N1 pandemic influenza (H1N1 pdm) virus. We identified a mechanism associated with the severe symptoms seen with H5N1 HPAI virus infection. H5N1 HPAI virus infection induced a decrease of dendritic cell number in the splenic extrafollicular T-cell zone and impaired formation of the outer layers of B-cell follicles, resulting in insufficient levels of antibody production after infection. However, in animals vaccinated with a live recombinant vaccinia virus expressing the H5 hemagglutinin, infection with H5N1 HPAI virus induced parafollicular dendritic cell accumulation and efficient antibody production. These results indicate that a recombinant vaccinia encoding H5 hemagglutinin gene does not impair dendritic cell recruitment and can be a useful vaccine candidate.

  4. Evaluation of twenty rapid antigen tests for the detection of human influenza A H5N1, H3N2, H1N1, and B viruses.

    Science.gov (United States)

    Taylor, Janette; McPhie, Kenneth; Druce, Julian; Birch, Chris; Dwyer, Dominic E

    2009-11-01

    Twenty rapid antigen assays were compared for their ability to detect influenza using dilutions of virus culture supernatants from human isolates of influenza A H5N1 (clade 1 and 2 strains), H3N2 and H1N1 viruses, and influenza B. There was variation amongst the rapid antigen assays in their ability to detect different influenza viruses. Six of the 12 assays labeled as distinguishing between influenza A and B had comparable analytical sensitivities for detecting both influenza A H5N1 strains, although their ability to detect influenza A H3N2 and H1N1 strains varied. The two assays claiming H5 specificity did not detect either influenza A H5N1 strains, and the two avian influenza-specific assays detected influenza A H5N1, but missed some influenza A H3N2 virus supernatants. Clinical trials of rapid antigen tests for influenza A H5N1 are limited. For use in a pandemic where novel influenza strains are circulating (such as the current novel influenza A H1N1 09 virus), rapid antigen tests should ideally have comparable sensitivity and specificity for the new strains as for co-circulating seasonal influenza strains.

  5. A duplex real-time RT-PCR assay for detecting H5N1 avian influenza virus and pandemic H1N1 influenza virus

    OpenAIRE

    Kang, Xiao-ping; Jiang, Tao; Li, Yong-qiang; Lin, Fang; Liu, Hong; Chang, Guo-hui; Zhu, Qing-yu; Qin, E-de; Qin, Cheng-feng; Yang, Yin-hui

    2010-01-01

    Abstract A duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay was improved for simultaneous detection of highly pathogenic H5N1 avian influenza virus and pandemic H1N1 (2009) influenza virus, which is suitable for early diagnosis of influenza-like patients and for epidemiological surveillance. The sensitivity of this duplex real-time RT-PCR assay was 0.02 TCID50 (50% tissue culture infective dose) for H5N1 and 0.2 TCID50 for the pandemic H1N1, which was the same a...

  6. A study of analysis PB1-F2 protein of Influenza Viruses A/H1N1pdm09, A/ H3N2, and A/H5N1

    Directory of Open Access Journals (Sweden)

    Hana Apsari Pawestri

    2016-07-01

    Full Text Available Abstrak Tujuan. Protein PB1-F2 (polymerase basic 1-frame 2 adalah protein terbaru yang ditemukan pada virus Influenza dan telah terbukti berperan dalam induksi kematian sel dan patogenitas. Tujuan dari tulisan ini adalah untuk menganalisis protein PB1-F2 pada virus Influenza A/H5N1 dan A/H1N1pdm09. Metode. Kami melakukan pencarian data yang relevan yaitu sekuens gen virus Influenza A/H5N1 dan A/H1N1pdm09 dari Gen Bank National Center for Biotechnology Information (NCBI selama tahun 1997-2015. Data yang digunakan adalah data sekuens nukleotida gen PB1 (polymerase basic1 virus influenza A/H5N1 dan A/H1N1pdm09. Kemudian dilakukan analisis alignment untuk mengetahui variasi protein dan mutasi yang berhubungan dengan patogenitas dan virulensi. Hasil. Kami melakukan penelitian terhadap sekuens PB1-F2 sebanyak 3262 influenza A/H5N1 dan 2472 Influenza A/H1N1pdm09. Hasil analisis menunjukkan bahwa semua sekuens A/H5N1 memiliki panjang yang penuh sebanyak 90 asam amino, kecuali influenza pandemi 2009 hanya memiliki panjang 87 asam amino. Kemudian, ditemukan mutasi yang berhubungan dengan virulensi yang ditunjukan dengan perubahan asam amino Asparagin (N menjadi Serin (S. Mutasi tersebut terjadi pada Influenza A/H5N1 sebanyak 8.5% dan Influenza A/H1N1pdm09 sebanyak 0.5%. Kesimpulan. Ditemukan beberapa variasi panjang asam amino dan mutasi penting pada sekuens PB1-F2 dari subtipe yang berbeda yaitu influenza A/H5N1 dan A/H1N1pdm09  yang mengindikasikan seleksi spesifik karena introduksi dan adaptasi terhadap inang yang berbeda. Diperlukan penelitian lanjutan untuk lebih memahami variasi dan kontribusi protein PB1-F2 tersebut terhadap virulensi dan patogenitas virus Influenza. Kata kunci : Patogenesis, Virus Influenza, Protein  PB1-F2 Abstract Aim. Influenza virus PB1-F2 (polymerase basic 1-frame 2 protein is a novel protein previously shown to be involved in cell death induction and pathogenesis. Here we analysis the PB1-F2 protein of Influenza virus A/H

  7. A study of analysis PB1-F2 protein of Influenza Viruses A/H1N1pdm09, A/ H3N2, and A/H5N1

    Directory of Open Access Journals (Sweden)

    Hana Apsari Pawestri

    2016-07-01

    Full Text Available Abstrak Tujuan. Protein PB1-F2 (polymerase basic 1-frame 2 adalah protein terbaru yang ditemukan pada virus Influenza dan telah terbukti berperan dalam induksi kematian sel dan patogenitas. Tujuan dari tulisan ini adalah untuk menganalisis protein PB1-F2 pada virus Influenza A/H5N1 dan A/H1N1pdm09. Metode. Kami melakukan pencarian data yang relevan yaitu sekuens gen virus Influenza A/H5N1 dan A/H1N1pdm09 dari Gen Bank National Center for Biotechnology Information (NCBI selama tahun 1997-2015. Data yang digunakan adalah data sekuens nukleotida gen PB1 (polymerase basic1 virus influenza A/H5N1 dan A/H1N1pdm09. Kemudian dilakukan analisis alignment untuk mengetahui variasi protein dan mutasi yang berhubungan dengan patogenitas dan virulensi. Hasil. Kami melakukan penelitian terhadap sekuens PB1-F2 sebanyak 3262 influenza A/H5N1 dan 2472 Influenza A/H1N1pdm09. Hasil analisis menunjukkan bahwa semua sekuens A/H5N1 memiliki panjang yang penuh sebanyak 90 asam amino, kecuali influenza pandemi 2009 hanya memiliki panjang 87 asam amino. Kemudian, ditemukan mutasi yang berhubungan dengan virulensi yang ditunjukan dengan perubahan asam amino Asparagin (N menjadi Serin (S. Mutasi tersebut terjadi pada Influenza A/H5N1 sebanyak 8.5% dan Influenza A/H1N1pdm09 sebanyak 0.5%. Kesimpulan. Ditemukan beberapa variasi panjang asam amino dan mutasi penting pada sekuens PB1-F2 dari subtipe yang berbeda yaitu influenza A/H5N1 dan A/H1N1pdm09  yang mengindikasikan seleksi spesifik karena introduksi dan adaptasi terhadap inang yang berbeda. Diperlukan penelitian lanjutan untuk lebih memahami variasi dan kontribusi protein PB1-F2 tersebut terhadap virulensi dan patogenitas virus Influenza. Kata kunci : Patogenesis, Virus Influenza, Protein  PB1-F2 Abstract Aim. Influenza virus PB1-F2 (polymerase basic 1-frame 2 protein is a novel protein previously shown to be involved in cell death induction and pathogenesis. Here we analysis the PB1-F2 protein of Influenza virus A/H

  8. A duplex real-time RT-PCR assay for detecting H5N1 avian influenza virus and pandemic H1N1 influenza virus

    Directory of Open Access Journals (Sweden)

    Qin E-de

    2010-06-01

    Full Text Available Abstract A duplex real-time reverse transcriptase polymerase chain reaction (RT-PCR assay was improved for simultaneous detection of highly pathogenic H5N1 avian influenza virus and pandemic H1N1 (2009 influenza virus, which is suitable for early diagnosis of influenza-like patients and for epidemiological surveillance. The sensitivity of this duplex real-time RT-PCR assay was 0.02 TCID50 (50% tissue culture infective dose for H5N1 and 0.2 TCID50 for the pandemic H1N1, which was the same as that of each single-target RT-PCR for pandemic H1N1 and even more sensitive for H5N1 with the same primers and probes. No cross reactivity of detecting other subtype influenza viruses or respiratory tract viruses was observed. Two hundred and thirty-six clinical specimens were tested by comparing with single real-time RT-PCR and result from the duplex assay was 100% consistent with the results of single real-time RT-PCR and sequence analysis.

  9. Experimental infection of clade 1.1.2 (H5N1), clade 2.3.2.1c (H5N1) and clade 2.3.4.4 (H5N6) highly pathogenic avian influenza viruses in dogs.

    Science.gov (United States)

    Lyoo, K S; Na, W; Phan, L V; Yoon, S W; Yeom, M; Song, D; Jeong, D G

    2017-12-01

    Since the emergence of highly pathogenic avian influenza (HPAI) H5N1 in Asia, the haemagglutinin (HA) gene of this virus lineage has continued to evolve in avian populations, and H5N1 lineage viruses now circulate concurrently worldwide. Dogs may act as an intermediate host, increasing the potential for zoonotic transmission of influenza viruses. Virus transmission and pathologic changes in HPAI clade 1.1.2 (H5N1)-, 2.3.2.1c (H5N1)- and 2.3.4.4 (H5N6)-infected dogs were investigated. Mild respiratory signs and antibody response were shown in dogs intranasally infected with the viruses. Lung histopathology showed lesions that were associated with moderate interstitial pneumonia in the infected dogs. In this study, HPAI H5N6 virus replication in dogs was demonstrated for the first time. Dogs have been suspected as a "mixing vessel" for reassortments between avian and human influenza viruses to occur. The replication of these three subtypes of the H5 lineage of HPAI viruses in dogs suggests that dogs could serve as intermediate hosts for avian-human influenza virus reassortment if they are also co-infected with human influenza viruses. © 2017 Blackwell Verlag GmbH.

  10. Avian influenza A (H5N1)

    NARCIS (Netherlands)

    de Jong, Menno D.; Hien, Tran Tinh

    2006-01-01

    Since their reemergence in 2003, highly pathogenic avian influenza A (H5N1) viruses have reached endemic levels among poultry in several southeast Asian countries and have caused a still increasing number of more than 100 reported human infections with high mortality. These developments have ignited

  11. Prior infection of chickens with H1N1 or H1N2 avian influenza elicits partial heterologous protection against highly pathogenic H5N1.

    Science.gov (United States)

    Nfon, Charles; Berhane, Yohannes; Pasick, John; Embury-Hyatt, Carissa; Kobinger, Gary; Kobasa, Darwyn; Babiuk, Shawn

    2012-01-01

    There is a critical need to have vaccines that can protect against emerging pandemic influenza viruses. Commonly used influenza vaccines are killed whole virus that protect against homologous and not heterologous virus. Using chickens we have explored the possibility of using live low pathogenic avian influenza (LPAI) A/goose/AB/223/2005 H1N1 or A/WBS/MB/325/2006 H1N2 to induce immunity against heterologous highly pathogenic avian influenza (HPAI) A/chicken/Vietnam/14/2005 H5N1. H1N1 and H1N2 replicated in chickens but did not cause clinical disease. Following infection, chickens developed nucleoprotein and H1 specific antibodies, and reduced H5N1 plaque size in vitro in the absence of H5 neutralizing antibodies at 21 days post infection (DPI). In addition, heterologous cell mediated immunity (CMI) was demonstrated by antigen-specific proliferation and IFN-γ secretion in PBMCs re-stimulated with H5N1 antigen. Following H5N1 challenge of both pre-infected and naïve controls chickens housed together, all naïve chickens developed acute disease and died while H1N1 or H1N2 pre-infected chickens had reduced clinical disease and 70-80% survived. H1N1 or H1N2 pre-infected chickens were also challenged with H5N1 and naïve chickens placed in the same room one day later. All pre-infected birds were protected from H5N1 challenge but shed infectious virus to naïve contact chickens. However, disease onset, severity and mortality was reduced and delayed in the naïve contacts compared to directly inoculated naïve controls. These results indicate that prior infection with LPAI virus can generate heterologous protection against HPAI H5N1 in the absence of specific H5 antibody.

  12. Prior infection of chickens with H1N1 or H1N2 avian influenza elicits partial heterologous protection against highly pathogenic H5N1.

    Directory of Open Access Journals (Sweden)

    Charles Nfon

    Full Text Available There is a critical need to have vaccines that can protect against emerging pandemic influenza viruses. Commonly used influenza vaccines are killed whole virus that protect against homologous and not heterologous virus. Using chickens we have explored the possibility of using live low pathogenic avian influenza (LPAI A/goose/AB/223/2005 H1N1 or A/WBS/MB/325/2006 H1N2 to induce immunity against heterologous highly pathogenic avian influenza (HPAI A/chicken/Vietnam/14/2005 H5N1. H1N1 and H1N2 replicated in chickens but did not cause clinical disease. Following infection, chickens developed nucleoprotein and H1 specific antibodies, and reduced H5N1 plaque size in vitro in the absence of H5 neutralizing antibodies at 21 days post infection (DPI. In addition, heterologous cell mediated immunity (CMI was demonstrated by antigen-specific proliferation and IFN-γ secretion in PBMCs re-stimulated with H5N1 antigen. Following H5N1 challenge of both pre-infected and naïve controls chickens housed together, all naïve chickens developed acute disease and died while H1N1 or H1N2 pre-infected chickens had reduced clinical disease and 70-80% survived. H1N1 or H1N2 pre-infected chickens were also challenged with H5N1 and naïve chickens placed in the same room one day later. All pre-infected birds were protected from H5N1 challenge but shed infectious virus to naïve contact chickens. However, disease onset, severity and mortality was reduced and delayed in the naïve contacts compared to directly inoculated naïve controls. These results indicate that prior infection with LPAI virus can generate heterologous protection against HPAI H5N1 in the absence of specific H5 antibody.

  13. Prophylactic and therapeutic efficacy of avian antibodies against influenza virus H5N1 and H1N1 in mice.

    Directory of Open Access Journals (Sweden)

    Huan H Nguyen

    Full Text Available BACKGROUND: Pandemic influenza poses a serious threat to global health and the world economy. While vaccines are currently under development, passive immunization could offer an alternative strategy to prevent and treat influenza virus infection. Attempts to develop monoclonal antibodies (mAbs have been made. However, passive immunization based on mAbs may require a cocktail of mAbs with broader specificity in order to provide full protection since mAbs are generally specific for single epitopes. Chicken immunoglobulins (IgY found in egg yolk have been used mainly for treatment of infectious diseases of the gastrointestinal tract. Because the recent epidemic of highly pathogenic avian influenza virus (HPAIV strain H5N1 has resulted in serious economic losses to the poultry industry, many countries including Vietnam have introduced mass vaccination of poultry with H5N1 virus vaccines. We reasoned that IgY from consumable eggs available in supermarkets in Vietnam could provide protection against infections with HPAIV H5N1. METHODS AND FINDINGS: We found that H5N1-specific IgY that are prepared from eggs available in supermarkets in Vietnam by a rapid and simple water dilution method cross-protect against infections with HPAIV H5N1 and related H5N2 strains in mice. When administered intranasally before or after lethal infection, the IgY prevent the infection or significantly reduce viral replication resulting in complete recovery from the disease, respectively. We further generated H1N1 virus-specific IgY by immunization of hens with inactivated H1N1 A/PR/8/34 as a model virus for the current pandemic H1N1/09 and found that such H1N1-specific IgY protect mice from lethal influenza virus infection. CONCLUSIONS: The findings suggest that readily available H5N1-specific IgY offer an enormous source of valuable biological material to combat a potential H5N1 pandemic. In addition, our study provides a proof-of-concept for the approach using virus

  14. Avian Influenza Virus (H5N1): a Threat to Human Health

    OpenAIRE

    Peiris, J. S. Malik; de Jong, Menno D.; Guan, Yi

    2007-01-01

    Pandemic influenza virus has its origins in avian influenza viruses. The highly pathogenic avian influenza virus subtype H5N1 is already panzootic in poultry, with attendant economic consequences. It continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. Therefore, H5N1 virus has rightly received attention as a potential pandemic threat. However, it is noted that the pandemics of 1957 and 1968 did not arise from highly pathogenic influenza viruses, ...

  15. Outbreaks of avian influenza A (H5N2), (H5N8), and (H5N1) among birds--United States, December 2014-January 2015.

    Science.gov (United States)

    Jhung, Michael A; Nelson, Deborah I

    2015-02-06

    During December 15, 2014-January 16, 2015, the U.S. Department of Agriculture received 14 reports of birds infected with Asian-origin, highly pathogenic avian influenza A (HPAI) (H5N2), (H5N8), and (H5N1) viruses. These reports represent the first reported infections with these viruses in U.S. wild or domestic birds. Although these viruses are not known to have caused disease in humans, their appearance in North America might increase the likelihood of human infection in the United States. Human infection with other avian influenza viruses, such as HPAI (H5N1) and (H5N6) viruses and (H7N9) virus, has been associated with severe, sometimes fatal, disease, usually following contact with poultry.

  16. Infection of mice with a human influenza A/H3N2 virus induces protective immunity against lethal infection with influenza A/H5N1 virus.

    Science.gov (United States)

    Kreijtz, J H C M; Bodewes, R; van den Brand, J M A; de Mutsert, G; Baas, C; van Amerongen, G; Fouchier, R A M; Osterhaus, A D M E; Rimmelzwaan, G F

    2009-08-06

    The transmission of highly pathogenic avian influenza (HPAI) A viruses of the H5N1 subtype from poultry to man and the high case fatality rate fuels the fear for a pandemic outbreak caused by these viruses. However, prior infections with seasonal influenza A/H1N1 and A/H3N2 viruses induce heterosubtypic immunity that could afford a certain degree of protection against infection with the HPAI A/H5N1 viruses, which are distantly related to the human influenza A viruses. To assess the protective efficacy of such heterosubtypic immunity mice were infected with human influenza virus A/Hong Kong/2/68 (H3N2) 4 weeks prior to a lethal infection with HPAI virus A/Indonesia/5/05 (H5N1). Prior infection with influenza virus A/Hong Kong/2/68 reduced clinical signs, body weight loss, mortality and virus replication in the lungs as compared to naive mice infected with HPAI virus A/Indonesia/5/05. Priming by infection with respiratory syncytial virus, a non-related virus did not have a beneficial effect on the outcome of A/H5N1 infections, indicating that adaptive immune responses were responsible for the protective effect. In mice primed by infection with influenza A/H3N2 virus cytotoxic T lymphocytes (CTL) specific for NP(366-374) epitope ASNENMDAM and PA(224-232) SCLENFRAYV were observed. A small proportion of these CTL was cross-reactive with the peptide variant derived from the influenza A/H5N1 virus (ASNENMEVM and SSLENFRAYV respectively) and upon challenge infection with the influenza A/H5N1 virus cross-reactive CTL were selectively expanded. These CTL, in addition to those directed to conserved epitopes, shared by the influenza A/H3N2 and A/H5N1 viruses, most likely contributed to accelerated clearance of the influenza A/H5N1 virus infection. Although also other arms of the adaptive immune response may contribute to heterosubtypic immunity, the induction of virus-specific CTL may be an attractive target for development of broad protective vaccines. Furthermore the

  17. Characterization of avian influenza H5N1 virosome

    Directory of Open Access Journals (Sweden)

    Chatchai Sarachai

    2014-04-01

    Full Text Available The purpose of this study was to prepare and characterize virosome containing envelope proteins of the avian influenza (H5N1 virus. The virosome was prepared by the solubilization of virus with octaethyleneglycol mono (n-dodecyl ether (C12E8 followed by detergent removal with SM2 Bio-Beads. Biochemical analysis by SDS-PAGE and western blotting, indicated that avian influenza H5N1 virosome had similar characteristics to the parent virus and contained both the hemagglutinin (HA, 60-75 kDa and neuraminidase (NA, 220 kDa protein, with preserved biological activity, such as hemagglutination activity. The virosome structure was analyzed by negative stained transmission electron microscope (TEM demonstrated that the spherical shapes of vesicles with surface glycoprotein spikes were harbored. In conclusion, the biophysical properties of the virosome were similar to the parent virus, and the use of octaethyleneglycol mono (n-dodecyl ether to solubilize viral membrane, followed by removal of detergent using polymer beads adsorption (Bio-Beads SM2 was the preferable method for obtaining avian influenza virosome. The outcome of this study might be useful for further development veterinary virus vaccines.

  18. Rapid and highly informative diagnostic assay for H5N1 influenza viruses.

    Directory of Open Access Journals (Sweden)

    Nader Pourmand

    Full Text Available A highly discriminative and information-rich diagnostic assay for H5N1 avian influenza would meet immediate patient care needs and provide valuable information for public health interventions, e.g., tracking of new and more dangerous variants by geographic area as well as avian-to-human or human-to-human transmission. In the present study, we have designed a rapid assay based on multilocus nucleic acid sequencing that focuses on the biologically significant regions of the H5N1 hemagglutinin gene. This allows the prediction of viral strain, clade, receptor binding properties, low- or high-pathogenicity cleavage site and glycosylation status. H5 HA genes were selected from nine known high-pathogenicity avian influenza subtype H5N1 viruses, based on their diversity in biologically significant regions of hemagglutinin and/or their ability to cause infection in humans. We devised a consensus pre-programmed pyrosequencing strategy, which may be used as a faster, more accurate alternative to de novo sequencing. The available data suggest that the assay described here is a reliable, rapid, information-rich and cost-effective approach for definitive diagnosis of H5N1 avian influenza. Knowledge of the predicted functional sequences of the HA will enhance H5N1 avian influenza surveillance efforts.

  19. Rapid detection of the avian influenza virus H5N1 subtype in Egypt

    African Journals Online (AJOL)

    Dr

    highly pathogenic avian influenza virus subtype H5N1 in Egypt is threatening poultry and ... Key words: Avian influenza virus, H5N1, fluorescent antibody enzyme-linked immunosorbent assay (ELISA) ..... poultry and is potentially zoonotic.

  20. Subclinical avian influenza A(H5N1) virus infection in human, Vietnam

    NARCIS (Netherlands)

    Le, Mai Quynh; Horby, Peter; Fox, Annette; Nguyen, Hien Tran; Le Nguyen, Hang Khanh; Hoang, Phuong Mai Vu; Nguyen, Khanh Cong; de Jong, Menno D.; Jeeninga, Rienk E.; Rogier van Doorn, H.; Farrar, Jeremy; Wertheim, Heiman F. L.

    2013-01-01

    Laboratory-confirmed cases of subclinical infection with avian influenza A(H5N1) virus in humans are rare, and the true number of these cases is unknown. We describe the identification of a laboratory-confirmed subclinical case in a woman during an influenza A(H5N1) contact investigation in northern

  1. Influenza A H5N1 and HIV co-infection: case report

    Directory of Open Access Journals (Sweden)

    Simmons Cameron

    2010-06-01

    Full Text Available Abstract Background The role of adaptive immunity in severe influenza is poorly understood. The occurrence of influenza A/H5N1 in a patient with HIV provided a rare opportunity to investigate this. Case Presentation A 30-year-old male was admitted on day 4 of influenza-like-illness with tachycardia, tachypnea, hypoxemia and bilateral pulmonary infiltrates. Influenza A/H5N1 and HIV tests were positive and the patient was treated with Oseltamivir and broad-spectrum antibiotics. Initially his condition improved coinciding with virus clearance by day 6. He clinically deteriorated as of day 10 with fever recrudescence and increasing neutrophil counts and died on day 16. His admission CD4 count was 100/μl and decreased until virus was cleared. CD8 T cells shifted to a CD27+CD28- phenotype. Plasma chemokine and cytokine levels were similar to those found previously in fatal H5N1. Conclusions The course of H5N1 infection was not notably different from other cases. Virus was cleared despite profound CD4 T cell depletion and aberrant CD8 T cell activation but this may have increased susceptibility to a fatal secondary infection.

  2. Advances and Future Challenges in Recombinant Adenoviral Vectored H5N1 Influenza Vaccines

    Directory of Open Access Journals (Sweden)

    Jianfeng Zhang

    2012-11-01

    Full Text Available The emergence of a highly pathogenic avian influenza virus H5N1 has increased the potential for a new pandemic to occur. This event highlights the necessity for developing a new generation of influenza vaccines to counteract influenza disease. These vaccines must be manufactured for mass immunization of humans in a timely manner. Poultry should be included in this policy, since persistent infected flocks are the major source of avian influenza for human infections. Recombinant adenoviral vectored H5N1 vaccines are an attractive alternative to the currently licensed influenza vaccines. This class of vaccines induces a broadly protective immunity against antigenically distinct H5N1, can be manufactured rapidly, and may allow mass immunization of human and poultry. Recombinant adenoviral vectors derived from both human and non-human adenoviruses are currently being investigated and appear promising both in nonclinical and clinical studies. This review will highlight the current status of various adenoviral vectored H5N1 vaccines and will outline novel approaches for the future.

  3. The influence of social-cognitive factors on personal hygiene practices to protect against influenzas: using modelling to compare avian A/H5N1 and 2009 pandemic A/H1N1 influenzas in Hong Kong.

    Science.gov (United States)

    Liao, Qiuyan; Cowling, Benjamin J; Lam, Wendy Wing Tak; Fielding, Richard

    2011-06-01

    Understanding population responses to influenza helps optimize public health interventions. Relevant theoretical frameworks remain nascent. To model associations between trust in information, perceived hygiene effectiveness, knowledge about the causes of influenza, perceived susceptibility and worry, and personal hygiene practices (PHPs) associated with influenza. Cross-sectional household telephone surveys on avian influenza A/H5N1 (2006) and pandemic influenza A/H1N1 (2009) gathered comparable data on trust in formal and informal sources of influenza information, influenza-related knowledge, perceived hygiene effectiveness, worry, perceived susceptibility, and PHPs. Exploratory factor analysis confirmed domain content while confirmatory factor analysis was used to evaluate the extracted factors. The hypothesized model, compiled from different theoretical frameworks, was optimized with structural equation modelling using the A/H5N1 data. The optimized model was then tested against the A/H1N1 dataset. The model was robust across datasets though corresponding path weights differed. Trust in formal information was positively associated with perceived hygiene effectiveness which was positively associated with PHPs in both datasets. Trust in formal information was positively associated with influenza worry in A/H5N1 data, and with knowledge of influenza cause in A/H1N1 data, both variables being positively associated with PHPs. Trust in informal information was positively associated with influenza worry in both datasets. Independent of information trust, perceived influenza susceptibility associated with influenza worry. Worry associated with PHPs in A/H5N1 data only. Knowledge of influenza cause and perceived PHP effectiveness were associated with PHPs. Improving trust in formal information should increase PHPs. Worry was significantly associated with PHPs in A/H5N1.

  4. Induction of long-term protective immune responses by influenza H5N1 virus-like particles.

    Directory of Open Access Journals (Sweden)

    Sang-Moo Kang

    Full Text Available Recurrent outbreaks of highly pathogenic H5N1 avian influenza virus pose a threat of eventually causing a pandemic. Early vaccination of the population would be the single most effective measure for the control of an emerging influenza pandemic.Influenza virus-like particles (VLPs produced in insect cell-culture substrates do not depend on the availability of fertile eggs for vaccine manufacturing. We produced VLPs containing influenza A/Viet Nam1203/04 (H5N1 hemagglutinin, neuraminidase, and matrix proteins, and investigated their preclinical immunogenicity and protective efficacy. Mice immunized intranasally with H5N1 VLPs developed high levels of H5N1 specific antibodies and were 100% protected against a high dose of homologous H5N1 virus infection at 30 weeks after immunization. Protection is likely to be correlated with humoral and cellular immunologic memory at systemic and mucosal sites as evidenced by rapid anamnestic responses to re-stimulation with viral antigen in vivo and in vitro.These results provide support for clinical evaluation of H5N1 VLP vaccination as a public health intervention to mitigate a possible pandemic of H5N1 influenza.

  5. Influenza H5N1 and H1N1 virus replication and innate immune responses in bronchial epithelial cells are influenced by the state of differentiation.

    Directory of Open Access Journals (Sweden)

    Renee W Y Chan

    Full Text Available Influenza H5N1 virus continues to be enzootic in poultry and transmits zoonotically to humans. Although a swine-origin H1N1 virus has emerged to become pandemic, its virulence for humans remains modest in comparison to that seen in zoonotic H5N1 disease. As human respiratory epithelium is the primary target cells for influenza viruses, elucidating the viral tropism and host innate immune responses of influenza H5N1 virus in human bronchial epithelium may help to understand the pathogenesis. Here we established primary culture of undifferentiated and well differentiated normal human bronchial epithelial (NHBE cells and infected with highly pathogenic influenza H5N1 virus (A/Vietnam/3046/2004 and a seasonal influenza H1N1 virus (A/Hong Kong/54/1998, the viral replication kinetics and cytokine and chemokine responses were compared by qPCR and ELISA. We found that the in vitro culture of the well differentiated NHBE cells acquired the physiological properties of normal human bronchi tissue which express high level of alpha2-6-linked sialic acid receptors and human airway trypsin-like (HAT protease, in contrast to the low expression in the non-differentiated NHBE cells. When compared to H1N1 virus, the H5N1 virus replicated more efficiently and induced a stronger type I interferon response in the undifferentiated NHBE cells. In contrast, in well differentiated cultures, H5N1 virus replication was less efficient and elicited a lower interferon-beta response in comparison with H1N1 virus. Our data suggest that the differentiation of bronchial epithelial cells has a major influence in cells' permissiveness to human H1N1 and avian H5N1 viruses and the host innate immune responses. The reduced virus replication efficiency partially accounts for the lower interferon-beta responses in influenza H5N1 virus infected well differentiated NHBE cells. Since influenza infection in the bronchial epithelium will lead to tissue damage and associate with the

  6. Avian influenza virus (H5N1): a threat to human health

    NARCIS (Netherlands)

    Peiris, J. S. Malik; de Jong, Menno D.; Guan, Yi

    2007-01-01

    Pandemic influenza virus has its origins in avian influenza viruses. The highly pathogenic avian influenza virus subtype H5N1 is already panzootic in poultry, with attendant economic consequences. It continues to cross species barriers to infect humans and other mammals, often with fatal outcomes.

  7. Differential host determinants contribute to the pathogenesis of 2009 pandemic H1N1 and human H5N1 influenza A viruses in experimental mouse models.

    Science.gov (United States)

    Otte, Anna; Sauter, Martina; Alleva, Lisa; Baumgarte, Sigrid; Klingel, Karin; Gabriel, Gülsah

    2011-07-01

    Influenza viruses are responsible for high morbidities in humans and may, eventually, cause pandemics. Herein, we compared the pathogenesis and host innate immune responses of a seasonal H1N1, two 2009 pandemic H1N1, and a human H5N1 influenza virus in experimental BALB/c and C57BL/6J mouse models. We found that both 2009 pandemic H1N1 isolates studied (A/Hamburg/05/09 and A/Hamburg/NY1580/09) were low pathogenic in BALB/c mice [log mouse lethal dose 50 (MLD(50)) >6 plaque-forming units (PFU)] but displayed remarkable differences in virulence in C57BL/6J mice. A/Hamburg/NY1580/09 was more virulent (logMLD(50) = 3.5 PFU) than A/Hamburg/05/09 (logMLD(50) = 5.2 PFU) in C57BL/6J mice. In contrast, the H5N1 influenza virus was more virulent in BALB/c mice (logMLD(50) = 0.3 PFU) than in C57BL/6J mice (logMLD(50) = 1.8 PFU). Seasonal H1N1 influenza revealed marginal pathogenicity in BALB/c or C57BL/6J mice (logMLD(50) >6 PFU). Enhanced susceptibility of C57BL/6J mice to pandemic H1N1 correlated with a depressed cytokine response. In contrast, enhanced H5N1 virulence in BALB/c mice correlated with an elevated proinflammatory cytokine response. These findings highlight that host determinants responsible for the pathogenesis of 2009 pandemic H1N1 influenza viruses are different from those contributing to H5N1 pathogenesis. Our results show, for the first time to our knowledge, that the C57BL/6J mouse strain is more appropriate for the evaluation and identification of intrinsic pathogenicity markers of 2009 pandemic H1N1 influenza viruses that are "masked" in BALB/c mice. Copyright © 2011 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  8. New Orf virus (Parapoxvirus) recombinant expressing H5 hemagglutinin protects mice against H5N1 and H1N1 influenza A virus.

    Science.gov (United States)

    Rohde, Jörg; Amann, Ralf; Rziha, Hanns-Joachim

    2013-01-01

    Previously we demonstrated the versatile utility of the Parapoxvirus Orf virus (ORFV) as a vector platform for the development of potent recombinant vaccines. In this study we present the generation of new ORFV recombinants expressing the hemagglutinin (HA) or nucleoprotein (NP) of the highly pathogenic avian influenza virus (HPAIV) H5N1. Correct foreign gene expression was examined in vitro by immunofluorescence, Western blotting and flow cytometry. The protective potential of both recombinants was evaluated in the mouse challenge model. Despite adequate expression of NP, the recombinant D1701-V-NPh5 completely failed to protect mice from lethal challenge. However, the H5 HA-expressing recombinant D1701-V-HAh5n mediated solid protection in a dose-dependent manner. Two intramuscular (i.m.) injections of the HA-expressing recombinant protected all animals from lethal HPAIV infection without loss of body weight. Notably, the immunized mice resisted cross-clade H5N1 and heterologous H1N1 (strain PR8) influenza virus challenge. In vivo antibody-mediated depletion of CD4-positive and/or CD8-posititve T-cell subpopulations during immunization and/or challenge infection implicated the relevance of CD4-positive T-cells for induction of protective immunity by D1701-V-HAh5n, whereas the absence of CD8-positive T-cells did not significantly influence protection. In summary, this study validates the potential of the ORFV vectored vaccines also to combat HPAIV.

  9. New Orf virus (Parapoxvirus recombinant expressing H5 hemagglutinin protects mice against H5N1 and H1N1 influenza A virus.

    Directory of Open Access Journals (Sweden)

    Jörg Rohde

    Full Text Available Previously we demonstrated the versatile utility of the Parapoxvirus Orf virus (ORFV as a vector platform for the development of potent recombinant vaccines. In this study we present the generation of new ORFV recombinants expressing the hemagglutinin (HA or nucleoprotein (NP of the highly pathogenic avian influenza virus (HPAIV H5N1. Correct foreign gene expression was examined in vitro by immunofluorescence, Western blotting and flow cytometry. The protective potential of both recombinants was evaluated in the mouse challenge model. Despite adequate expression of NP, the recombinant D1701-V-NPh5 completely failed to protect mice from lethal challenge. However, the H5 HA-expressing recombinant D1701-V-HAh5n mediated solid protection in a dose-dependent manner. Two intramuscular (i.m. injections of the HA-expressing recombinant protected all animals from lethal HPAIV infection without loss of body weight. Notably, the immunized mice resisted cross-clade H5N1 and heterologous H1N1 (strain PR8 influenza virus challenge. In vivo antibody-mediated depletion of CD4-positive and/or CD8-posititve T-cell subpopulations during immunization and/or challenge infection implicated the relevance of CD4-positive T-cells for induction of protective immunity by D1701-V-HAh5n, whereas the absence of CD8-positive T-cells did not significantly influence protection. In summary, this study validates the potential of the ORFV vectored vaccines also to combat HPAIV.

  10. Recombinant Parainfluenza Virus 5 Expressing Hemagglutinin of Influenza A Virus H5N1 Protected Mice against Lethal Highly Pathogenic Avian Influenza Virus H5N1 Challenge

    Science.gov (United States)

    Li, Zhuo; Mooney, Alaina J.; Gabbard, Jon D.; Gao, Xiudan; Xu, Pei; Place, Ryan J.; Hogan, Robert J.; Tompkins, S. Mark

    2013-01-01

    A safe and effective vaccine is the best way to prevent large-scale highly pathogenic avian influenza virus (HPAI) H5N1 outbreaks in the human population. The current FDA-approved H5N1 vaccine has serious limitations. A more efficacious H5N1 vaccine is urgently needed. Parainfluenza virus 5 (PIV5), a paramyxovirus, is not known to cause any illness in humans. PIV5 is an attractive vaccine vector. In our studies, a single dose of a live recombinant PIV5 expressing a hemagglutinin (HA) gene of H5N1 (rPIV5-H5) from the H5N1 subtype provided sterilizing immunity against lethal doses of HPAI H5N1 infection in mice. Furthermore, we have examined the effect of insertion of H5N1 HA at different locations within the PIV5 genome on the efficacy of a PIV5-based vaccine. Interestingly, insertion of H5N1 HA between the leader sequence, the de facto promoter of PIV5, and the first viral gene, nucleoprotein (NP), did not lead to a viable virus. Insertion of H5N1 HA between NP and the next gene, V/phosphorprotein (V/P), led to a virus that was defective in growth. We have found that insertion of H5N1 HA at the junction between the small hydrophobic (SH) gene and the hemagglutinin-neuraminidase (HN) gene gave the best immunity against HPAI H5N1 challenge: a dose as low as 1,000 PFU was sufficient to protect against lethal HPAI H5N1 challenge in mice. The work suggests that recombinant PIV5 expressing H5N1 HA has great potential as an HPAI H5N1 vaccine. PMID:23077314

  11. Human influenza A (H5N1): a brief review and recommendations for travelers.

    Science.gov (United States)

    Hurtado, Timothy R

    2006-01-01

    Although avian influenza A (H5N1) is common in birds worldwide, it has only recently led to disease in humans. Humans who are infected with the disease (referred to as human influenza A [H5N1]) have a greater than 50% mortality rate. Currently there has not been documented sustained human-to-human transmission; however, should the virus mutate and make this possible, the world could experience an influenza pandemic. Probable risk factors for infection include slaughtering, defeathering, and butchering fowl; close contact with wild birds or caged poultry; ingestion of undercooked poultry products; direct contact with surfaces contaminated with poultry feces; and close contact with infected humans. Possible risk factors include swimming in or ingesting water contaminated with bird feces or dead birds and the use of unprocessed poultry feces as fertilizer. Clinically, early human influenza A (H5N1) resembles typical influenza illnesses, with fever and a preponderance of lower respiratory tract symptoms. Often, patients develop rapidly progressive respiratory failure and require ventilatory support. Treatment is primarily supportive care with the addition of antiviral medications. Currently, travelers to countries with both human and avian influenza A (H5N1) have a low risk of developing the disease. There are no current recommended travel restrictions. Travelers are advised to avoid contact with all birds, especially poultry; avoid surfaces contaminated with poultry feces; and avoid undercooked poultry products. The use of prophylactic antiviral medications is not recommended.

  12. Homosubtypic and heterosubtypic antibodies against highly pathogenic avian influenza H5N1 recombinant proteins in H5N1 survivors and non-H5N1 subjects.

    Science.gov (United States)

    Noisumdaeng, Pirom; Pooruk, Phisanu; Prasertsopon, Jarunee; Assanasen, Susan; Kitphati, Rungrueng; Auewarakul, Prasert; Puthavathana, Pilaipan

    2014-04-01

    Six recombinant vaccinia viruses containing HA, NA, NP, M or NS gene insert derived from a highly pathogenic avian influenza H5N1 virus, and the recombinant vaccinia virus harboring plasmid backbone as the virus control were constructed. The recombinant proteins were characterized for their expression and subcellular locations in TK(-) cells. Antibodies to the five recombinant proteins were detected in all 13 sequential serum samples collected from four H5N1 survivors during four years of follow-up; and those directed to rVac-H5 HA and rVac-NA proteins were found in higher titers than those directed to the internal proteins as revealed by indirect immunofluorescence assay. Although all 28 non-H5N1 subjects had no neutralizing antibodies against H5N1 virus, they did have cross-reactive antibodies to those five recombinant proteins. A significant increase in cross-reactive antibody titer to rVac-H5 HA and rVac-NA was found in paired blood samples from patients infected with the 2009 pandemic virus. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Estimation of transmission parameters of H5N1 avian influenza virus in chickens.

    Directory of Open Access Journals (Sweden)

    Annemarie Bouma

    2009-01-01

    Full Text Available Despite considerable research efforts, little is yet known about key epidemiological parameters of H5N1 highly pathogenic influenza viruses in their avian hosts. Here we show how these parameters can be estimated using a limited number of birds in experimental transmission studies. Our quantitative estimates, based on Bayesian methods of inference, reveal that (i the period of latency of H5N1 influenza virus in unvaccinated chickens is short (mean: 0.24 days; 95% credible interval: 0.099-0.48 days; (ii the infectious period of H5N1 virus in unvaccinated chickens is approximately 2 days (mean: 2.1 days; 95%CI: 1.8-2.3 days; (iii the reproduction number of H5N1 virus in unvaccinated chickens need not be high (mean: 1.6; 95%CI: 0.90-2.5, although the virus is expected to spread rapidly because it has a short generation interval in unvaccinated chickens (mean: 1.3 days; 95%CI: 1.0-1.5 days; and (iv vaccination with genetically and antigenically distant H5N2 vaccines can effectively halt transmission. Simulations based on the estimated parameters indicate that herd immunity may be obtained if at least 80% of chickens in a flock are vaccinated. We discuss the implications for the control of H5N1 avian influenza virus in areas where it is endemic.

  14. Newcastle disease virus-based H5 influenza vaccine protects chickens from lethal challenge with a highly pathogenic H5N2 avian influenza virus

    OpenAIRE

    Ma, Jingjiao; Lee, Jinhwa; Liu, Haixia; Mena, Ignacio; Davis, A. Sally; Sunwoo, Sun Young; Lang, Yuekun; Duff, Michael; Morozov, Igor; Li, Yuhao; Yang, Jianmei; García-Sastre, Adolfo; Richt, Juergen A.; Ma, Wenjun

    2017-01-01

    Since December 2014, Eurasian-origin, highly pathogenic avian influenza H5 viruses including H5N1, H5N2, and H5N8 subtypes (called H5Nx viruses), which belong to the H5 clade 2.3.4.4, have been detected in U.S. wild birds. Subsequently, highly pathogenic H5N2 and H5N8 viruses have caused outbreaks in U.S. domestic poultry. Vaccination is one of the most effective ways to control influenza outbreaks and protect animal and public health. Newcastle disease virus (NDV)-based influenza vaccines ha...

  15. Inactivation of influenza A virus H1N1 by disinfection process.

    Science.gov (United States)

    Jeong, Eun Kyo; Bae, Jung Eun; Kim, In Seop

    2010-06-01

    Because any patient, health care worker, or visitor is capable of transmitting influenza to susceptible persons within hospitals, hospital-acquired influenza has been a clinical concern. Disinfection and cleaning of medical equipment, surgical instruments, and hospital environment are important measures to prevent transmission of influenza virus from hospitals to individuals. This study was conducted to evaluate the efficacy of disinfection processes, which can be easily operated at hospitals, in inactivating influenza A virus H1N1 (H1N1). The effects of 0.1 mol/L NaOH, 70% ethanol, 70% 1-propanol, solvent/detergent (S/D) using 0.3% tri (n-butyl)-phosphate and 1.0% Triton X-100, heat, and ethylene oxide (EO) treatments in inactivating H1N1 were determined. Inactivation of H1N1 was kinetically determined by the treatment of disinfectants to virus solution. Also, a surface test method, which involved drying an amount of virus on a surface and then applying the inactivation methods for 1 minute of contact time, was used to determine the virucidal activity. H1N1 was completely inactivated to undetectable levels in 1 minute of 70% ethanol, 70% 1-propanol, and solvent/detergent treatments in the surface tests as well as in the suspension tests. H1N1 was completely inactivated in 1 minute of 0.1 mol/L NaOH treatment in the suspension tests and also effectively inactivated in the surface tests with the log reduction factor of 3.7. H1N1 was inactivated to undetectable levels within 5 minutes, 2.5 minutes, and 1 minute of heat treatment at 70, 80, and 90 degrees C, respectively in the suspension tests. Also, H1N1 was completely inactivated by EO treatment in the surface tests. Common disinfectants, heat, and EO tested in this study were effective at inactivating H1N1. These results would be helpful in implementing effective disinfecting measures to prevent hospital-acquired infections. Copyright 2010 Association for Professionals in Infection Control and Epidemiology, Inc

  16. Avian influenza H5N1 viral and bird migration networks in Asia

    Science.gov (United States)

    Tian, Huaivu; Zhou, Sen; Dong, Lu; Van Boeckel, Thomas P.; Cui, Yujun; Newman, Scott H.; Takekawa, John Y.; Prosser, Diann J.; Xiao, Xiangming; Wu, Yarong; Cazelles, Bernard; Huang, Shanqian; Yang, Ruifu; Grenfell, Bryan T.; Xu, Bing

    2015-01-01

    The spatial spread of the highly pathogenic avian influenza virus H5N1 and its long-term persistence in Asia have resulted in avian influenza panzootics and enormous economic losses in the poultry sector. However, an understanding of the regional long-distance transmission and seasonal patterns of the virus is still lacking. In this study, we present a phylogeographic approach to reconstruct the viral migration network. We show that within each wild fowl migratory flyway, the timing of H5N1 outbreaks and viral migrations are closely associated, but little viral transmission was observed between the flyways. The bird migration network is shown to better reflect the observed viral gene sequence data than other networks and contributes to seasonal H5N1 epidemics in local regions and its large-scale transmission along flyways. These findings have potentially far-reaching consequences, improving our understanding of how bird migration drives the periodic reemergence of H5N1 in Asia.

  17. Treatment and Prevention of Pandemic H1N1 Influenza.

    Science.gov (United States)

    Rewar, Suresh; Mirdha, Dashrath; Rewar, Prahlad

    2015-01-01

    Swine influenza is a respiratory infection common to pigs worldwide caused by type A influenza viruses, principally subtypes H1N1, H1N2, H2N1, H3N1, H3N2, and H2N3. Swine influenza viruses also can cause moderate to severe illness in humans and affect persons of all age groups. People in close contact with swine are at especially high risk. Until recently, epidemiological study of influenza was limited to resource-rich countries. The World Health Organization declared an H1N1 pandemic on June 11, 2009, after more than 70 countries reported 30,000 cases of H1N1 infection. In 2015, incidence of swine influenza increased substantially to reach a 5-year high. In India in 2015, 10,000 cases of swine influenza were reported with 774 deaths. The Centers for Disease Control and Prevention recommend real-time polymerase chain reaction as the method of choice for diagnosing H1N1. Antiviral drugs are the mainstay of clinical treatment of swine influenza and can make the illness milder and enable the patient to feel better faster. Antiviral drugs are most effective when they are started within the first 48 hours after the clinical signs begin, although they also may be used in severe or high-risk cases first seen after this time. The Centers for Disease Control and Prevention recommends use of oseltamivir (Tamiflu, Genentech) or zanamivir (Relenza, GlaxoSmithKline). Prevention of swine influenza has 3 components: prevention in swine, prevention of transmission to humans, and prevention of its spread among humans. Because of limited treatment options, high risk for secondary infection, and frequent need for intensive care of individuals with H1N1 pneumonia, environmental control, including vaccination of high-risk populations and public education are critical to control of swine influenza out breaks. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Serosurvey of antibody to highly pathogenic avian influenza (H5N1 ...

    African Journals Online (AJOL)

    Avian influenza is a disease of economic and public health importance that has been described in most domestic animals and humans. Highly pathogenic avian influenza H5N1 epidemic in Nigeria was observed in agro-ecological zones where pigs and chickens are raised in shared environment with chances of ...

  19. The emergence of influenza A H7N9 in human beings 16 years after influenza A H5N1: a tale of two cities.

    Science.gov (United States)

    To, Kelvin K W; Chan, Jasper F W; Chen, Honglin; Li, Lanjuan; Yuen, Kwok-Yung

    2013-09-01

    Infection with either influenza A H5N1 virus in 1997 or avian influenza A H7N9 virus in 2013 caused severe pneumonia that did not respond to typical or atypical antimicrobial treatment, and resulted in high mortality. Both viruses are reassortants with internal genes derived from avian influenza A H9N2 viruses that circulate in Asian poultry. Both viruses have genetic markers of mammalian adaptation in their haemagglutinin and polymerase PB2 subunits, which enhanced binding to human-type receptors and improved replication in mammals, respectively. Hong Kong (affected by H5N1 in 1997) and Shanghai (affected by H7N9 in 2013) are two rapidly flourishing cosmopolitan megacities that were increasing in human population and poultry consumption before the outbreaks. Both cities are located along the avian migratory route at the Pearl River delta and Yangtze River delta. Whether the widespread use of the H5N1 vaccine in east Asia-with suboptimum biosecurity measures in live poultry markets and farms-predisposed to the emergence of H7N9 or other virus subtypes needs further investigation. Why H7N9 seems to be more readily transmitted from poultry to people than H5N1 is still unclear. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. Live bird markets of Bangladesh: H9N2 viruses and the near absence of highly pathogenic H5N1 influenza.

    Directory of Open Access Journals (Sweden)

    Nicholas J Negovetich

    2011-04-01

    Full Text Available Avian influenza surveillance in Bangladesh has been passive, relying on poultry farmers to report suspected outbreaks of highly pathogenic H5N1 influenza. Here, the results of an active surveillance effort focusing on the live-bird markets are presented. Prevalence of influenza infection in the birds of the live bird markets is 23.0%, which is similar to that in poultry markets in other countries. Nearly all of the isolates (94% were of the non-pathogenic H9N2 subtype, but viruses of the H1N2, H1N3, H3N6, H4N2, H5N1, and H10N7 subtypes were also observed. The highly pathogenic H5N1-subtype virus was observed at extremely low prevalence in the surveillance samples (0.08%, and we suggest that the current risk of infection for humans in the retail poultry markets in Bangladesh is negligible. However, the high prevalence of the H9 subtype and its potential for interaction with the highly pathogenic H5N1-subtype, i.e., reassortment and attenuation of host morbidity, highlight the importance of active surveillance of the poultry markets.

  1. Acid Stability of the Hemagglutinin Protein Regulates H5N1 Influenza Virus Pathogenicity

    Energy Technology Data Exchange (ETDEWEB)

    DuBois, Rebecca M.; Zaraket, Hassan; Reddivari, Muralidhar; Heath, Richard J.; White, Stephen W.; Russell, Charles J. (Tennessee-HSC); (SJCH)

    2012-12-10

    Highly pathogenic avian influenza viruses of the H5N1 subtype continue to threaten agriculture and human health. Here, we use biochemistry and x-ray crystallography to reveal how amino-acid variations in the hemagglutinin (HA) protein contribute to the pathogenicity of H5N1 influenza virus in chickens. HA proteins from highly pathogenic (HP) A/chicken/Hong Kong/YU562/2001 and moderately pathogenic (MP) A/goose/Hong Kong/437-10/1999 isolates of H5N1 were found to be expressed and cleaved in similar amounts, and both proteins had similar receptor-binding properties. However, amino-acid variations at positions 104 and 115 in the vestigial esterase sub-domain of the HA1 receptor-binding domain (RBD) were found to modulate the pH of HA activation such that the HP and MP HA proteins are activated for membrane fusion at pH 5.7 and 5.3, respectively. In general, an increase in H5N1 pathogenicity in chickens was found to correlate with an increase in the pH of HA activation for mutant and chimeric HA proteins in the observed range of pH 5.2 to 6.0. We determined a crystal structure of the MP HA protein at 2.50 {angstrom} resolution and two structures of HP HA at 2.95 and 3.10 {angstrom} resolution. Residues 104 and 115 that modulate the acid stability of the HA protein are situated at the N- and C-termini of the 110-helix in the vestigial esterase sub-domain, which interacts with the B loop of the HA2 stalk domain. Interactions between the 110-helix and the stalk domain appear to be important in regulating HA protein acid stability, which in turn modulates influenza virus replication and pathogenesis. Overall, an optimal activation pH of the HA protein is found to be necessary for high pathogenicity by H5N1 influenza virus in avian species.

  2. A highly pathogenic avian influenza virus H5N1 with 2009 pandemic H1N1 internal genes demonstrated increased replication and transmission in pigs

    Science.gov (United States)

    This study investigated the pathogenicity and transmissibility of a reverse-genetics derived highly pathogenic avian influenza (HPAI) H5N1 influenza A virus (IAV), A/Iraq/775/06, and a reassortant virus comprised of the HA and NA from A/Iraq/775/06 and the internal genes of a 2009 pandemic H1N1, A/N...

  3. An H5N1-based matrix protein 2 ectodomain tetrameric peptide vaccine provides cross-protection against lethal infection with H7N9 influenza virus.

    Science.gov (United States)

    Leung, Ho-Chuen; Chan, Chris Chung-Sing; Poon, Vincent Kwok-Man; Zhao, Han-Jun; Cheung, Chung-Yan; Ng, Fai; Huang, Jian-Dong; Zheng, Bo-Jian

    2015-04-01

    In March 2013, a patient infected with a novel avian influenza A H7N9 virus was reported in China. Since then, there have been 458 confirmed infection cases and 177 deaths. The virus contains several human-adapted markers, indicating that H7N9 has pandemic potential. The outbreak of this new influenza virus highlighted the need for the development of universal influenza vaccines. Previously, we demonstrated that a tetrameric peptide vaccine based on the matrix protein 2 ectodomain (M2e) of the H5N1 virus (H5N1-M2e) could protect mice from lethal infection with different clades of H5N1 and 2009 pandemic H1N1 influenza viruses. In this study, we investigated the cross-protection of H5N1-M2e against lethal infection with the new H7N9 virus. Although five amino acid differences existed at positions 13, 14, 18, 20, and 21 between M2e of H5N1 and H7N9, H5N1-M2e vaccination with either Freund's adjuvant or the Sigma adjuvant system (SAS) induced a high level of anti-M2e antibody, which cross-reacted with H7N9-M2e peptide. A mouse-adapted H7N9 strain, A/Anhui/01/2013m, was used for lethal challenge in animal experiments. H5N1-M2e vaccination provided potent cross-protection against lethal challenge of the H7N9 virus. Reduced viral replication and histopathological damage of mouse lungs were also observed in the vaccinated mice. Our results suggest that the tetrameric H5N1-M2e peptide vaccine could protect against different subtypes of influenza virus infections. Therefore, this vaccine may be an ideal candidate for developing a universal vaccine to prevent the reemergence of avian influenza A H7N9 virus and the emergence of potential novel reassortants of influenza virus.

  4. Transforming growth factor-β: activation by neuraminidase and role in highly pathogenic H5N1 influenza pathogenesis.

    Directory of Open Access Journals (Sweden)

    Christina M Carlson

    2010-10-01

    Full Text Available Transforming growth factor-beta (TGF-β, a multifunctional cytokine regulating several immunologic processes, is expressed by virtually all cells as a biologically inactive molecule termed latent TGF-β (LTGF-β. We have previously shown that TGF-β activity increases during influenza virus infection in mice and suggested that the neuraminidase (NA protein mediates this activation. In the current study, we determined the mechanism of activation of LTGF-β by NA from the influenza virus A/Gray Teal/Australia/2/1979 by mobility shift and enzyme inhibition assays. We also investigated whether exogenous TGF-β administered via a replication-deficient adenovirus vector provides protection from H5N1 influenza pathogenesis and whether depletion of TGF-β during virus infection increases morbidity in mice. We found that both the influenza and bacterial NA activate LTGF-β by removing sialic acid motifs from LTGF-β, each NA being specific for the sialic acid linkages cleaved. Further, NA likely activates LTGF-β primarily via its enzymatic activity, but proteases might also play a role in this process. Several influenza A virus subtypes (H1N1, H1N2, H3N2, H5N9, H6N1, and H7N3 except the highly pathogenic H5N1 strains activated LTGF-β in vitro and in vivo. Addition of exogenous TGF-β to H5N1 influenza virus-infected mice delayed mortality and reduced viral titers whereas neutralization of TGF-β during H5N1 and pandemic 2009 H1N1 infection increased morbidity. Together, these data show that microbe-associated NAs can directly activate LTGF-β and that TGF-β plays a pivotal role protecting the host from influenza pathogenesis.

  5. Ferrets develop fatal influenza after inhaling small particle aerosols of highly pathogenic avian influenza virus A/Vietnam/1203/2004 (H5N1

    Directory of Open Access Journals (Sweden)

    Sosna William A

    2010-09-01

    Full Text Available Abstract Background There is limited knowledge about the potential routes for H5N1 influenza virus transmission to and between humans, and it is not clear whether humans can be infected through inhalation of aerosolized H5N1 virus particles. Ferrets are often used as a animal model for humans in influenza pathogenicity and transmissibility studies. In this manuscript, a nose-only bioaerosol inhalation exposure system that was recently developed and validated was used in an inhalation exposure study of aerosolized A/Vietnam/1203/2004 (H5N1 virus in ferrets. The clinical spectrum of influenza resulting from exposure to A/Vietnam/1203/2004 (H5N1 through intranasal verses inhalation routes was analyzed. Results Ferrets were successfully infected through intranasal instillation or through inhalation of small particle aerosols with four different doses of Influenza virus A/Vietnam/1203/2004 (H5N1. The animals developed severe influenza encephalomyelitis following intranasal or inhalation exposure to 101, 102, 103, or 104 infectious virus particles per ferret. Conclusions Aerosolized Influenza virus A/Vietnam/1203/2004 (H5N1 is highly infectious and lethal in ferrets. Clinical signs appeared earlier in animals infected through inhalation of aerosolized virus compared to those infected through intranasal instillation.

  6. Influenza H5N1 virus infection of polarized human alveolar epithelial cells and lung microvascular endothelial cells

    Directory of Open Access Journals (Sweden)

    Yuen Kit M

    2009-10-01

    Full Text Available Abstract Background Highly pathogenic avian influenza (HPAI H5N1 virus is entrenched in poultry in Asia and Africa and continues to infect humans zoonotically causing acute respiratory disease syndrome and death. There is evidence that the virus may sometimes spread beyond respiratory tract to cause disseminated infection. The primary target cell for HPAI H5N1 virus in human lung is the alveolar epithelial cell. Alveolar epithelium and its adjacent lung microvascular endothelium form host barriers to the initiation of infection and dissemination of influenza H5N1 infection in humans. These are polarized cells and the polarity of influenza virus entry and egress as well as the secretion of cytokines and chemokines from the virus infected cells are likely to be central to the pathogenesis of human H5N1 disease. Aim To study influenza A (H5N1 virus replication and host innate immune responses in polarized primary human alveolar epithelial cells and lung microvascular endothelial cells and its relevance to the pathogenesis of human H5N1 disease. Methods We use an in vitro model of polarized primary human alveolar epithelial cells and lung microvascular endothelial cells grown in transwell culture inserts to compare infection with influenza A subtype H1N1 and H5N1 viruses via the apical or basolateral surfaces. Results We demonstrate that both influenza H1N1 and H5N1 viruses efficiently infect alveolar epithelial cells from both apical and basolateral surface of the epithelium but release of newly formed virus is mainly from the apical side of the epithelium. In contrast, influenza H5N1 virus, but not H1N1 virus, efficiently infected polarized microvascular endothelial cells from both apical and basolateral aspects. This provides a mechanistic explanation for how H5N1 virus may infect the lung from systemic circulation. Epidemiological evidence has implicated ingestion of virus-contaminated foods as the source of infection in some instances and our

  7. Highly Pathogenic H5N1 Avian Influenza Viruses Exhibit Few Barriers to Gene Flow in Vietnam

    Science.gov (United States)

    Carrel, Margaret; Wan, Xiu-Feng; Nguyen, Tung; Emch, Michael

    2013-01-01

    Locating areas where genetic change is inhibited can illuminate underlying processes that drive evolution of pathogens. The persistence of highly pathogenic H5N1 avian influenza in Vietnam since 2003, and the continuous molecular evolution of Vietnamese avian influenza viruses, indicates that local environmental factors are supportive not only of incidence but also of viral adaptation. This article explores whether gene flow is constant across Vietnam, or whether there exist boundary areas where gene flow exhibits discontinuity. Using a dataset of 125 highly pathogenic H5N1 avian influenza viruses, principal components analysis and wombling analysis are used to indicate the location, magnitude, and statistical significance of genetic boundaries. Results show that a small number of geographically minor boundaries to gene flow in highly pathogenic H5N1 avian influenza viruses exist in Vietnam, but that overall there is little division in genetic exchange. This suggests that differences in genetic characteristics of viruses from one region to another are not the result of barriers to H5N1 viral exchange in Vietnam, and that H5N1 avian influenza is able to spread relatively unimpeded across the country. PMID:22350419

  8. Reassortant H1N1 influenza virus vaccines protect pigs against pandemic H1N1 influenza virus and H1N2 swine influenza virus challenge.

    Science.gov (United States)

    Yang, Huanliang; Chen, Yan; Shi, Jianzhong; Guo, Jing; Xin, Xiaoguang; Zhang, Jian; Wang, Dayan; Shu, Yuelong; Qiao, Chuanling; Chen, Hualan

    2011-09-28

    Influenza A (H1N1) virus has caused human influenza outbreaks in a worldwide pandemic since April 2009. Pigs have been found to be susceptible to this influenza virus under experimental and natural conditions, raising concern about their potential role in the pandemic spread of the virus. In this study, we generated a high-growth reassortant virus (SC/PR8) that contains the hemagglutinin (HA) and neuraminidase (NA) genes from a novel H1N1 isolate, A/Sichuan/1/2009 (SC/09), and six internal genes from A/Puerto Rico/8/34 (PR8) virus, by genetic reassortment. The immunogenicity and protective efficacy of this reassortant virus were evaluated at different doses in a challenge model using a homologous SC/09 or heterologous A/Swine/Guangdong/1/06(H1N2) virus (GD/06). Two doses of SC/PR8 virus vaccine elicited high-titer serum hemagglutination inhibiting (HI) antibodies specific for the 2009 H1N1 virus and conferred complete protection against challenge with either SC/09 or GD/06 virus, with reduced lung lesions and viral shedding in vaccine-inoculated animals compared with non-vaccinated control animals. These results indicated for the first time that a high-growth SC/PR8 reassortant H1N1 virus exhibits properties that are desirable to be a promising vaccine candidate for use in swine in the event of a pandemic H1N1 influenza. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Purification of neuraminidase from Influenza virus subtype H5N1

    Directory of Open Access Journals (Sweden)

    Simson Tariga

    2009-03-01

    Full Text Available Influenza-virus neuraminidase plays vital role in the survival of the organisms. Vaccination of animals with this glycoprotein confers immune responses so that enable it to protect the animals from incoming infection. Supplementation of conventional vaccines with this glycoprotein increases the protection and longevity of the vaccine. Purified neuraminidase can also be used to develop serological tests for differentiation of serologically positive animals due to infection or to vaccination. In this study purification of neuraminidase from influenza virus subtype H5N1 was described. Triton x-100 and Octyl β-D-glucopyranoside were used to extract and diluted the glycoprotein membrane. The enzymatic activity of the neuraminidase was assayed using a fluorochrome substrate, 4-methylumbelliferyl-a-D-N-acetyl neuraminic acid, which was found to be simple, sensitive and suitable for the purification purpose. The neuraminidase was absorbed selectively on an oxamic-acid agarose column. The purity of neuraminidase eluted from this affinity column was high. A higher purity of the neuraminidase was obtained by further separation with gel filtration on Superdex-200. The purified neuraminidase was enzymatically active and did not contain any detectable haemagglutinin, either by haemagglutination assay or by monospecific antibodies raised against H5N1 hemagglutinin. The purified neuraminidase was recognized strongly by antibodies raised against an internal but only weakly by that against C-terminal regions of the neuraminidase protein of H5N1-influenza virus. The purified neuraminidase was in tetrameric forms but dissociated into monomeric form on reducing condition, or mostly dimeric form on non-reducing SDS-PAGE.

  10. Inefficient Transmission of H5N1 Influenza Viruses in a Ferret Contact Model▿

    OpenAIRE

    Yen, Hui-Ling; Lipatov, Aleksandr S.; Ilyushina, Natalia A.; Govorkova, Elena A.; Franks, John; Yilmaz, Neziha; Douglas, Alan; Hay, Alan; Krauss, Scott; Rehg, Jerold E.; Hoffmann, Erich; Webster, Robert G.

    2007-01-01

    The abilities to infect and transmit efficiently among humans are essential for a novel influenza A virus to cause a pandemic. To evaluate the pandemic potential of widely disseminated H5N1 influenza viruses, a ferret contact model using experimental groups comprised of one inoculated ferret and two contact ferrets was used to study the transmissibility of four human H5N1 viruses isolated from 2003 to 2006. The effects of viral pathogenicity and receptor binding specificity (affinity to synth...

  11. Virulence of H5N1 Influenza Virus in Cattle Egrets (Bubulcus Ibis)

    DEFF Research Database (Denmark)

    Phuong, Do Quy; Dung, Nguyen Tien; Jørgensen, Poul Henrik

    2011-01-01

    for insect control in households. In this study, six Cattle Egrets were experimentally infected intranasally with highly pathogenic avian influenza (AI) A/duck/Vietnam/40D/04 (H5N1) to investigate a possible epidemiologic role for Cattle Egrets in outbreaks of H5N1 AI in Vietnam. The Cattle Egrets were...

  12. Predicting Avian Influenza Co-Infection with H5N1 and H9N2 in Northern Egypt

    Directory of Open Access Journals (Sweden)

    Sean G. Young

    2016-09-01

    Full Text Available Human outbreaks with avian influenza have been, so far, constrained by poor viral adaptation to non-avian hosts. This could be overcome via co-infection, whereby two strains share genetic material, allowing new hybrid strains to emerge. Identifying areas where co-infection is most likely can help target spaces for increased surveillance. Ecological niche modeling using remotely-sensed data can be used for this purpose. H5N1 and H9N2 influenza subtypes are endemic in Egyptian poultry. From 2006 to 2015, over 20,000 poultry and wild birds were tested at farms and live bird markets. Using ecological niche modeling we identified environmental, behavioral, and population characteristics of H5N1 and H9N2 niches within Egypt. Niches differed markedly by subtype. The subtype niches were combined to model co-infection potential with known occurrences used for validation. The distance to live bird markets was a strong predictor of co-infection. Using only single-subtype influenza outbreaks and publicly available ecological data, we identified areas of co-infection potential with high accuracy (area under the receiver operating characteristic (ROC curve (AUC 0.991.

  13. Probable Tiger-to-Tiger Transmission of Avian Influenza H5N1

    Science.gov (United States)

    Thanawongnuwech, Roongroje; Amonsin, Alongkorn; Tantilertcharoen, Rachod; Damrongwatanapokin, Sudarat; Theamboonlers, Apiradee; Payungporn, Sunchai; Nanthapornphiphat, Kamonchart; Ratanamungklanon, Somchuan; Tunak, Eakchai; Songserm, Thaweesak; Vivatthanavanich, Veravit; Lekdumrongsak, Thawat; Kesdangsakonwut, Sawang; Tunhikorn, Schwann

    2005-01-01

    During the second outbreak of avian influenza H5N1 in Thailand, probable horizontal transmission among tigers was demonstrated in the tiger zoo. Sequencing and phylogenetic analysis of those viruses showed no differences from the first isolate obtained in January 2004. This finding has implications for influenza virus epidemiology and pathogenicity in mammals. PMID:15890122

  14. Comparison of temporal and spatial dynamics of seasonal H3N2, pandemic H1N1 and highly pathogenic avian influenza H5N1 virus infections in ferrets.

    Directory of Open Access Journals (Sweden)

    Judith M A van den Brand

    Full Text Available Humans may be infected by different influenza A viruses--seasonal, pandemic, and zoonotic--which differ in presentation from mild upper respiratory tract disease to severe and sometimes fatal pneumonia with extra-respiratory spread. Differences in spatial and temporal dynamics of these infections are poorly understood. Therefore, we inoculated ferrets with seasonal H3N2, pandemic H1N1 (pH1N1, and highly pathogenic avian H5N1 influenza virus and performed detailed virological and pathological analyses at time points from 0.5 to 14 days post inoculation (dpi, as well as describing clinical signs and hematological parameters. H3N2 infection was restricted to the nose and peaked at 1 dpi. pH1N1 infection also peaked at 1 dpi, but occurred at similar levels throughout the respiratory tract. H5N1 infection occurred predominantly in the alveoli, where it peaked for a longer period, from 1 to 3 dpi. The associated lesions followed the same spatial distribution as virus infection, but their severity peaked between 1 and 6 days later. Neutrophil and monocyte counts in peripheral blood correlated with inflammatory cell influx in the alveoli. Of the different parameters used to measure lower respiratory tract disease, relative lung weight and affected lung tissue allowed the best quantitative distinction between the virus groups. There was extra-respiratory spread to more tissues--including the central nervous system--for H5N1 infection than for pH1N1 infection, and to none for H3N2 infection. This study shows that seasonal, pandemic, and zoonotic influenza viruses differ strongly in the spatial and temporal dynamics of infection in the respiratory tract and extra-respiratory tissues of ferrets.

  15. Features of pathology in mice experimentally infected with highly pathogenic H5N1 influenza virus

    International Nuclear Information System (INIS)

    Ryabchikova, E. I.; Taranov, O. S.; Malkova, E. M.; Gritsyk, O. B.; Demina, O. K.

    2009-01-01

    Avian influenza became a new threat and has set people thinking about possibility of new influenza pandemic which may be caused by highly pathogenic H5N1 influenza virus. The virus could acquire ability of fast spreading between the humans and new pandemics could kill millions. Influenza virus H5N1 exhibited its deadly essence by taking out many millions of birds in nature and aviculture; other millions of chicks and ducks were killed to prevent spread of the epizootic. The strains isolated in Russia belong to Qinghai group of H5N1 influenza virus, and were imported to Russia by migratory birds. We examined time-course changes in mice blood and lungs after intranasal infection with strains A /Chicken/ Kurgan/ 05/2005, A/ Duck/ Kurgan/08/ 2005 and A/ Chicken/ Suzdalka/ Nov-11/2005 differing in virulence for this animal species. Development of leucopenia and severe damage of hemopoiesis were found in mice infected with all H5N1 influenza virus strains. Pathological changes in mice lungs during the infection with above mentioned strains, and strain-specific features have been examined. Main characteristics of lung pathology in all mice were focal nature of the alterations, severe damage of bronchial epithelium and pronounced alteration of lung vasculature. Strain A/Chicken/Suzdalka/Nov-11/2005 induced massive apoptosis of infected bronchial cells which may be a part of mechanism responsible for avirulent properties of this strain. The most interesting finding was absence of serious direct virus damage of the lung evidencing for principal role of the host humoral mechanisms in pathogenesis of H5N1 influenza in mice.(author)

  16. 2.1 Natural History of Highly Pathogenic Avian Influenza H5N1

    Science.gov (United States)

    Sonnberg, Stephanie; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    The ecology of highly pathogenic avian influenza (HPAI) H5N1 has significantly changed from sporadic outbreaks in terrestrial poultry to persistent circulation in terrestrial and aquatic poultry and potentially in wild waterfowl. A novel genotype of HPAI H5N1 arose in 1996 in southern China and through ongoing mutation, reassortment, and natural selection, has diverged into distinct lineages and expanded into multiple reservoir hosts. The evolution of Goose/Guangdong-lineage highly pathogenic H5N1 viruses is ongoing: while stable interactions exist with some reservoir hosts, these viruses are continuing to evolve and adapt to others, and pose an un-calculable risk to sporadic hosts, including humans. PMID:23735535

  17. Epidemiology of avian influenza H5N1 virus in Egypt and its zoonotic potential

    Directory of Open Access Journals (Sweden)

    Nahed Hamed Ghoneim

    2014-09-01

    Full Text Available Objective: To investigate the epidemiology of avian influenza H5N1 virus in domestic poultry and its zoonotic potential in Egypt. Methods: Tracheal swabs were collected from two hundred and forty three domestic poultry (chickens, ducks and geese from commercial farms and backyards, and thirty two blood samples from unvaccinated chickens. Fifty two throat swabs and twenty blood samples were collected from persons who are in contact with diseased and/or infected birds. Tracheal and throat swabs were examined for the presence of avian influenza virus H5N1 genome by real-time RT-PCR whereas blood samples were tested by competitive ELISA for the presence of avian influenza virus H5 antibodies. Results: The overall prevalence of H5N1 in the examined birds was 5.3% while the prevalence rates among different poultry species were 9%, 4.7% and 0% for ducks, chicken and geese respectively. Moreover, we detected H5 antibodies in 12.5% of the examined backyard chickens. All examined humans were negative for both viral RNA and antibodies. Conclusions: Our findings highlight the broad circulation of H5N1 virus among poultry in Egypt whereas it still has a limited zoonotic potential so far.

  18. Adaptation of high-growth influenza H5N1 vaccine virus in Vero cells: implications for pandemic preparedness.

    Directory of Open Access Journals (Sweden)

    Yu-Fen Tseng

    Full Text Available Current egg-based influenza vaccine production technology can't promptly meet the global demand during an influenza pandemic as shown in the 2009 H1N1 pandemic. Moreover, its manufacturing capacity would be vulnerable during pandemics caused by highly pathogenic avian influenza viruses. Therefore, vaccine production using mammalian cell technology is becoming attractive. Current influenza H5N1 vaccine strain (NIBRG-14, a reassortant virus between A/Vietnam/1194/2004 (H5N1 virus and egg-adapted high-growth A/PR/8/1934 virus, could grow efficiently in eggs and MDCK cells but not Vero cells which is the most popular cell line for manufacturing human vaccines. After serial passages and plaque purifications of the NIBRG-14 vaccine virus in Vero cells, one high-growth virus strain (Vero-15 was generated and can grow over 10(8 TCID(50/ml. In conclusion, one high-growth H5N1 vaccine virus was generated in Vero cells, which can be used to manufacture influenza H5N1 vaccines and prepare reassortant vaccine viruses for other influenza A subtypes.

  19. Signal Immune Reactions of Macrophages Differentiated from THP-1 Monocytes to Infection with Pandemic H1N1PDM09 Virus and H5N2 and H9N2 Avian Influenza A Virus.

    Science.gov (United States)

    Sokolova, T M; Poloskov, V V; Shuvalov, A N; Rudneva, I A; Timofeeva, T A

    2018-03-01

    In culture of THP-1 cells differentiated into macrophages with PMA (THP-PMA macrophages) infected with influenza viruses of subtypes H1, H5 and H9, we measured the expression of TLR7 and RIG1 receptor genes, sensors of viral RNA and ribonucleoprotein, and the levels of production of inflammatory cytokines IL-1β, TNFα, IL-10, and IFNα. The sensitivity and inflammatory response of THP-PMA macrophages to pandemic influenza A virus H1N1pdm09 and avian influenza H5N2 and H9N2 viruses correlate with the intracellular level of their viral RNA and activation of the RIG1 gene. Abortive infection is accompanied by intensive macrophage secretion of TNFα, IL-1β, and toxic factors inducing cell death. Activity of endosomal TLR7 receptor gene changed insignificantly in 24 h after infection and significantly decreased in 48 and 72 h under the action of H5N2 and H9N2, which correlated with manifestation of the cytopathogenic effect of these viruses. H5N2 and H9N2 avian viruses in THP-PMA macrophages are strong activators of the expression of the gene of the cytoplasmic RIG1 receptor 24 and 48 h after infection, and the pandemic virus H1N1pdm09 is a weak stimulator of RIG1 gene. Avian influenza H5N2 and H9N2 viruses are released by rapid induction of the inflammatory response in macrophages. At the late stages of infection, we observed a minor increase in IL-10 secretion in macrophages and, probably, the polarization of a part of the population in type M2. The studied influenza A viruses are weak inductors of IFN in THP-PMA macrophages. In the culture medium of THP-PMA macrophages infected with H9N2 and H5N2 viruses, MTT test revealed high levels of toxic factors causing the death of Caco-2 cells. In contrast to avian viruses, pandemic virus H1N1pdm09 did not induce production of toxic factors.

  20. H5N1 avian influenza virus: human cases reported in southern China.

    NARCIS (Netherlands)

    Crofts, J.; Paget, J.; Karcher, F.

    2003-01-01

    Two cases of confirmed influenza due to the avian influenza A H5N1 virus were reported last week in Hong Kong (1). The cases occurred in a Hong Kong family who had recently visited Fujian province in southern China. The daughter, aged 8 years, died following a respiratory illness. The cause of her

  1. Evidence for common ancestry among viruses isolated from wild birds in Beringia and highly pathogenic intercontinental reassortant H5N1 and H5N2 influenza A viruses

    Science.gov (United States)

    Ramey, Andy M.; Reeves, Andrew; Teslaa, Joshua L.; Nashold, Sean W.; Donnelly, Tyrone F.; Bahl, Justin; Hall, Jeffrey S.

    2016-01-01

    Highly pathogenic clade 2.3.4.4 H5N8, H5N2, and H5N1 influenza A viruses were first detected in wild, captive, and domestic birds in North America in November–December 2014. In this study, we used wild waterbird samples collected in Alaska prior to the initial detection of clade 2.3.4.4 H5 influenza A viruses in North America to assess the evidence for: (1) dispersal of highly pathogenic influenza A viruses from East Asia to North America by migratory birds via Alaska and (2) ancestral origins of clade 2.3.4.4 H5 reassortant viruses in Beringia. Although we did not detect highly pathogenic influenza A viruses in our sample collection from western Alaska, we did identify viruses that contained gene segments sharing recent common ancestry with intercontinental reassortant H5N2 and H5N1 viruses. Results of phylogenetic analyses and estimates for times of most recent common ancestry support migratory birds sampled in Beringia as maintaining viral diversity closely related to novel highly pathogenic influenza A virus genotypes detected in North America. Although our results do not elucidate the route by which highly pathogenic influenza A viruses were introduced into North America, genetic evidence is consistent with the hypothesized trans-Beringian route of introduction via migratory birds.

  2. Psychosocial effects assocPsychosocial effects associated with highly pathogenic avian influenza (H5N1 in Nigeriaiated with highly pathogenic avian influenza (H5N1 in Nigeria

    Directory of Open Access Journals (Sweden)

    Chiara Rafanelli

    2010-12-01

    Full Text Available Highly pathogenic avian influenza H5N1 (HPAI H5N1 infected poultry in Nigeria in 2006. The outbreaks caused significant economic losses and had serious zoonotic repercussions. The outbreaks have also had psychosocial effects on Nigerian farmers. To date, empirical data on the effect of outbreaks on humans are scarce. In this study, field data on HPAI H5N1 in Nigeria were analysed. Although only one human case leading to death was reported in Nigeria, the fact that HPAI H5N1 caused a human death created a disruption in social order and in the well-being of farmers (stress, altered livelihood and trauma and affected the rural economy. The implication of the above on health communication, the importance of successful control measures in poultry and policy implementation are stressed. Further studies are encouraged.

  3. Presence of serum antibodies to influenza A subtypes H5 and N1 in swans and ibises in French wetlands, irrespective of highly pathogenic H5N1 natural infection.

    Science.gov (United States)

    Niqueux, Eric; Guionie, Olivier; Schmitz, Audrey; Hars, Jean; Jestin, Véronique

    2010-03-01

    Highly pathogenic (HP) avian influenza A viruses (AIVs) subtype H5N1 (subclade 2.2) were detected in wild birds during outbreaks in France during winter 2006 and summer 2007 in la Dombes wetlands (eastern France) and in Moselle wetlands (northeastern France), respectively. Blood samples from apparently healthy wild birds were collected in 2006 and 2007 from the end of the outbreak to several weeks after the influenza A outbreak inside and outside the contaminated areas, and in 2008 outside the contaminated areas. The samples were tested for the presence and/or quantitation of serum antibodies to influenza A subtypes H5 and N1 using hemagglutination inhibition tests (HITs), a commercial N1-specific enzyme-linked immunosorbent assay kit, and virus neutralization assay. In the HIT, low pathogenicity (LP) and HP H5 AIVs (belonging to H5N1, H5N2, and H5N3 subtypes) were used as antigens. One hundred mute swans were bled in the la Dombes outbreak area in 2006. During 2007, 46 mallards, 69 common pochards, and 59 mute swans were sampled in the Moselle outbreak area. For comparison, blood samples were also collected in 2007 from 60 mute swans from the Marne department where no HP H5N1 influenza A cases have been reported, and in 2008 from 111 sacred ibises in western France where no HP H5N1 influenza A infections in wild birds have been reported either. Mute swans (irrespective of their origin and time of sampling) and sacred ibises (from an area with no known outbreaks) had the highest prevalence of positive sera in the H5 HIT (49-69% and 64%, respectively). The prevalence of anti-H5 antibodies in mallards and common pochards was lower (28% and 27%, respectively). Positive H5- and N1-antibody responses were also significantly associated in swans (irrespective of their origin and time of sampling) and in sacred ibises. However, in swans from the area without outbreaks, the HIT titer against an H5N1 LPAIV was significantly higher than against an H5N1 2.2.1 HPAIV, whereas no

  4. 75 FR 69046 - Notice of Determination of the High Pathogenic Avian Influenza Subtype H5N1 Status of Czech...

    Science.gov (United States)

    2010-11-10

    ... Avian Influenza Subtype H5N1 Status of Czech Republic and Sweden AGENCY: Animal and Plant Health... the highly pathogenic avian influenza (HPAI) subtype H5N1 status of the Czech Republic and Sweden... status of the Czech Republic and Sweden relative to highly pathogenic avian influenza (HPAI) subtype H5N1...

  5. Reassortant H9N2 influenza viruses containing H5N1-like PB1 genes isolated from black-billed magpies in Southern China.

    Directory of Open Access Journals (Sweden)

    Guoying Dong

    Full Text Available H9N2 influenza A viruses have become endemic in different types of terrestrial poultry and wild birds in Asia, and are occasionally transmitted to humans and pigs. To evaluate the role of black-billed magpies (Pica pica in the evolution of influenza A virus, we conducted two epidemic surveys on avian influenza viruses in wild black-billed magpies in Guangxi, China in 2005 and characterized three isolated black-billed magpie H9N2 viruses (BbM viruses. Phylogenetic analysis indicated that three BbM viruses were almost identical with 99.7 to 100% nucleotide homology in their whole genomes, and were reassortants containing BJ94-like (Ck/BJ/1/94 HA, NA, M, and NS genes, SH/F/98-like (Ck/SH/F/98 PB2, PA, and NP genes, and H5N1-like (Ck/YN/1252/03, clade 1 PB1 genes. Genetic analysis showed that BbM viruses were most likely the result of multiple reassortments between co-circulating H9N2-like and H5N1-like viruses, and were genetically different from other H9N2 viruses because of the existence of H5N1-like PB1 genes. Genotypical analysis revealed that BbM viruses evolved from diverse sources and belonged to a novel genotype (B46 discovered in our recent study. Molecular analysis suggested that BbM viruses were likely low pathogenic reassortants. However, results of our pathogenicity study demonstrated that BbM viruses replicated efficiently in chickens and a mammalian mouse model but were not lethal for infected chickens and mice. Antigenic analysis showed that BbM viruses were antigenic heterologous with the H9N2 vaccine strain. Our study is probably the first report to document and characterize H9N2 influenza viruses isolated from black-billed magpies in southern China. Our results suggest that black-billed magpies were susceptible to H9N2 influenza viruses, which raise concerns over possible transmissions of reassortant H9N2 viruses among poultry and wild birds.

  6. Seroprevalence survey of avian influenza A(H5N1) among live poultry market workers in northern Viet Nam, 2011.

    Science.gov (United States)

    Dung, Tham Chi; Dinh, Pham Ngoc; Nam, Vu Sinh; Tan, Luong Minh; Hang, Nguyen Le Khanh; Thanh, Le Thi; Mai, Le Quynh

    2014-01-01

    Highly pathogenic avian influenza A(H5N1) is endemic in poultry in Viet Nam. The country has experienced the third highest number of human infections with influenza A(H5N1) in the world. A study in Hanoi in 2001, before the epizootic that was identified in 2003, found influenza A(H5N1) specific antibodies in 4% of poultry market workers (PMWs). We conducted a seroprevalence survey to determine the seroprevalence of antibodies to influenza A(H5N1) among PMWs in Hanoi, Thaibinh and Thanhhoa provinces. We selected PMWs from five markets, interviewed them and collected blood samples. These were then tested using a horse haemagglutination inhibition assay and a microneutralization assay with all three clades of influenza A(H5N1) viruses that have circulated in Viet Nam since 2004. The overall seroprevalence was 6.1% (95% confidence interval: 4.6-8.3). The highest proportion (7.2%) was found in PMWs in Hanoi, and the majority of seropositive subjects (70.3%) were slaughterers or sellers of poultry. The continued circulation and evolution of influenza A(H5N1) requires comprehensive surveillance of both human and animal sites throughout the country with follow-up studies on PMWs to estimate the risk of avian-human transmission of influenza A(H5N1) in Viet Nam.

  7. Influenza A (H1N1) organising pneumonia.

    Science.gov (United States)

    Torrego, Alfons; Pajares, Virginia; Mola, Anna; Lerma, Enrique; Franquet, Tomás

    2010-04-27

    In November 2009, countries around the world reported confirmed cases of pandemic influenza H1N1, including over 6000 deaths. No peak in activity has been seen. The most common causes of death are pneumonia and acute respiratory distress syndrome. We report a case of a 55-year-old woman who presented with organising pneumonia associated with influenza A (H1N1) infection confirmed by transbronchial lung biopsy. Organising pneumonia should also be considered as a possible complication of influenza A (H1N1) infection, given that these patients can benefit from early diagnosis and appropriate specific management.

  8. Physician's knowledge, attitudes, and practices regarding seasonal influenza, pandemic influenza, and highly pathogenic avian influenza A (H5N1) virus infections of humans in Indonesia

    OpenAIRE

    Mangiri, Amalya; Iuliano, A. Danielle; Wahyuningrum, Yunita; Praptiningsih, Catharina Y.; Lafond, Kathryn E.; Storms, Aaron D.; Samaan, Gina; Ariawan, Iwan; Soeharno, Nugroho; Kreslake, Jennifer M.; Storey, J. Douglas; Uyeki, Timothy M.

    2016-01-01

    Indonesia has reported highest number of fatal human cases of highly pathogenic avian influenza (HPAI) A (H5N1) virus infection worldwide since 2005. There are limited data available on seasonal and pandemic influenza in Indonesia. During 2012, we conducted a survey of clinicians in two districts in western Java, Indonesia, to assess knowledge, attitudes, and practices (KAP) of clinical diagnosis, testing, and treatment of patients with seasonal influenza, pandemic influenza, or HPAI H5N1 vir...

  9. Highly pathogenic avian influenza H5N1 in Mainland China

    NARCIS (Netherlands)

    X.-L. Li (Xin-Lou); K. Liu (Kun); H.-W. Yao (Hong-Wu); Y. Sun (Ye); W.-J. Chen (Wan-Jun); R.-X. Sun (Ruo-Xi); S.J. de Vlas (Sake); L.Q. Fang (Lily); W.-C. Cao (Wu-Chun)

    2015-01-01

    textabstractHighly pathogenic avian influenza (HPAI) H5N1 has posed a significant threat to both humans and birds, and it has spanned large geographic areas and various ecological systems throughout Asia, Europe and Africa, but especially in mainland China. Great efforts in control and prevention of

  10. Human infection with highly pathogenic H5N1 influenza virus

    NARCIS (Netherlands)

    Gambotto, Andrea; Barratt-Boyes, Simon M.; de Jong, Menno D.; Neumann, Gabriele; Kawaoka, Yoshihiro

    2008-01-01

    Highly pathogenic H5N1 influenza A viruses have spread relentlessly across the globe since 2003, and they are associated with widespread death in poultry, substantial economic loss to farmers, and reported infections of more than 300 people with a mortality rate of 60%. The high pathogenicity of

  11. Protection against H5N1 Highly Pathogenic Avian and Pandemic (H1N1) 2009 Influenza Virus Infection in Cynomolgus Monkeys by an Inactivated H5N1 Whole Particle Vaccine

    Science.gov (United States)

    Nakayama, Misako; Shichinohe, Shintaro; Itoh, Yasushi; Ishigaki, Hirohito; Kitano, Mitsutaka; Arikata, Masahiko; Pham, Van Loi; Ishida, Hideaki; Kitagawa, Naoko; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Ichikawa, Takaya; Tsuchiya, Hideaki; Nakamura, Shinichiro; Le, Quynh Mai; Ito, Mutsumi; Kawaoka, Yoshihiro; Kida, Hiroshi; Ogasawara, Kazumasa

    2013-01-01

    H5N1 highly pathogenic avian influenza virus (HPAIV) infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3), in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1) 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3. PMID:24376571

  12. Protection against H5N1 highly pathogenic avian and pandemic (H1N1 2009 influenza virus infection in cynomolgus monkeys by an inactivated H5N1 whole particle vaccine.

    Directory of Open Access Journals (Sweden)

    Misako Nakayama

    Full Text Available H5N1 highly pathogenic avian influenza virus (HPAIV infection has been reported in poultry and humans with expanding clade designations. Therefore, a vaccine that induces immunity against a broad spectrum of H5N1 viruses is preferable for pandemic preparedness. We established a second H5N1 vaccine candidate, A/duck/Hokkaido/Vac-3/2007 (Vac-3, in our virus library and examined the efficacy of inactivated whole particles of this strain against two clades of H5N1 HPAIV strains that caused severe morbidity in cynomolgus macaques. Virus propagation in vaccinated macaques infected with either of the H5N1 HPAIV strains was prevented compared with that in unvaccinated macaques. This vaccine also prevented propagation of a pandemic (H1N1 2009 virus in macaques. In the vaccinated macaques, neutralization activity, which was mainly shown by anti-hemagglutinin antibody, against H5N1 HPAIVs in plasma was detected, but that against H1N1 virus was not detected. However, neuraminidase inhibition activity in plasma and T-lymphocyte responses in lymph nodes against H1N1 virus were detected. Therefore, cross-clade and heterosubtypic protective immunity in macaques consisted of humoral and cellular immunity induced by vaccination with Vac-3.

  13. Seroprevalence survey of avian influenza A(H5N1 among live poultry market workers in northern Viet Nam, 2011

    Directory of Open Access Journals (Sweden)

    Tham Chi Dung

    2014-11-01

    Full Text Available Objective: Highly pathogenic avian influenza A(H5N1 is endemic in poultry in Viet Nam. The country has experienced the third highest number of human infections with influenza A(H5N1 in the world. A study in Hanoi in 2001, before the epizootic that was identified in 2003, found influenza A(H5N1 specific antibodies in 4% of poultry market workers (PMWs. We conducted a seroprevalence survey to determine the seroprevalence of antibodies to influenza A(H5N1 among PMWs in Hanoi, Thaibinh and Thanhhoa provinces. Methods: We selected PMWs from five markets, interviewed them and collected blood samples. These were then tested using a horse haemagglutination inhibition assay and a microneutralization assay with all three clades of influenza A(H5N1 viruses that have circulated in Viet Nam since 2004. Results: The overall seroprevalence was 6.1% (95% confidence interval: 4.6–8.3. The highest proportion (7.2% was found in PMWs in Hanoi, and the majority of seropositive subjects (70.3% were slaughterers or sellers of poultry. Discussion: The continued circulation and evolution of influenza A(H5N1 requires comprehensive surveillance of both human and animal sites throughout the country with follow-up studies on PMWs to estimate the risk of avian–human transmission of influenza A(H5N1 in Viet Nam.

  14. The special neuraminidase stalk-motif responsible for increased virulence and pathogenesis of H5N1 influenza A virus.

    Directory of Open Access Journals (Sweden)

    Hongbo Zhou

    Full Text Available The variation of highly pathogenic avian influenza H5N1 virus results in gradually increased virulence in poultry, and human cases continue to accumulate. The neuraminidase (NA stalk region of influenza virus varies considerably and may associate with its virulence. The NA stalk region of all N1 subtype influenza A viruses can be divided into six different stalk-motifs, H5N1/2004-like (NA-wt, WSN-like, H5N1/97-like, PR/8-like, H7N1/99-like and H5N1/96-like. The NA-wt is a special NA stalk-motif which was first observed in H5N1 influenza virus in 2000, with a 20-amino acid deletion in the 49(th to 68(th positions of the stalk region. Here we show that there is a gradual increase of the special NA stalk-motif in H5N1 isolates from 2000 to 2007, and notably, the special stalk-motif is observed in all 173 H5N1 human isolates from 2004 to 2007. The recombinant H5N1 virus with the special stalk-motif possesses the highest virulence and pathogenicity in chicken and mice, while the recombinant viruses with the other stalk-motifs display attenuated phenotype. This indicates that the special stalk-motif has contributed to the high virulence and pathogenicity of H5N1 isolates since 2000. The gradually increasing emergence of the special NA stalk-motif in H5N1 isolates, especially in human isolates, deserves attention by all.

  15. Thermal inactivation of H5N2 high-pathogenicity avian influenza virus in dried egg white with 7.5% moisture.

    Science.gov (United States)

    Thomas, Colleen; Swayne, David E

    2009-09-01

    High-pathogenicity avian influenza viruses (HPAIV) cause severe systemic disease with high mortality in chickens. Isolation of HPAIV from the internal contents of chicken eggs has been reported, and this is cause for concern because HPAIV can be spread by movement of poultry products during marketing and trade activity. This study presents thermal inactivation data for the HPAIV strain A/chicken/PA/1370/83 (H5N2) (PA/83) in dried egg white with a moisture content (7.5%) similar to that found in commercially available spray-dried egg white products. The 95% upper confidence limits for D-values calculated from linear regression of the survival curves at 54.4, 60.0, 65.5, and 71.1 degrees C were 475.4, 192.2, 141.0, and 50.1 min, respectively. The line equation y = [0.05494 x degrees C] + 5.5693 (root mean square error = 0.0711) was obtained by linear regression of experimental D-values versus temperature. Conservative predictions based on the thermal inactivation data suggest that standard industry pasteurization protocols would be very effective for HPAIV inactivation in dried egg white. For example, these calculations predict that a 7-log reduction would take only 2.6 days at 54.4 degrees C.

  16. Mucosal immunity induced by adenovirus-based H5N1 HPAI vaccine confers protection against a lethal H5N2 avian influenza virus challenge

    International Nuclear Information System (INIS)

    Park, Ki Seok; Lee, Jiyeung; Ahn, So Shin; Byun, Young-Ho; Seong, Baik Lin; Baek, Yun Hee; Song, Min-Suk; Choi, Young Ki; Na, Yun Jeong; Hwang, Inhwan; Sung, Young Chul; Lee, Chang Geun

    2009-01-01

    Development of effective vaccines against highly pathogenic avian influenza (HPAI) H5N1 viruses is a global public health priority. Considering the difficulty in predicting HPAI H5N1 pandemic strains, one strategy used in their design includes the development of formulations with the capacity of eliciting broad cross-protective immunity against multiple viral antigens. To this end we constructed a replication-defective recombinant adenovirus-based avian influenza virus vaccine (rAdv-AI) expressing the codon-optimized M2eX-HA-hCD40L and the M1-M2 fusion genes from HPAI H5N1 human isolate. Although there were no significant differences in the systemic immune responses observed between the intramuscular prime-intramuscular boost regimen (IM/IM) and the intranasal prime-intramuscular boost regimen (IN/IM), IN/IM induced more potent CD8 + T cell and antibody responses at mucosal sites than the IM/IM vaccination, resulting in more effective protection against lethal H5N2 avian influenza (AI) virus challenge. These findings suggest that the strategies used to induce multi-antigen-targeted mucosal immunity, such as IN/IM delivery of rAdv-AI, may be a promising approach for developing broad protective vaccines that may be more effective against the new HPAI pandemic strains.

  17. Influenza A (H1N1) neuraminidase inhibitors from Vitis amurensis

    DEFF Research Database (Denmark)

    Nguyen, Ngoc Anh; Dao, Trong Tuan; Tung, Bui Thanh

    2011-01-01

    Recently, a novel H1N1 influenza A virus (H1N1/09 virus) was identified and considered a strong candidate for a novel influenza pandemic. As part of an ongoing anti-influenza screening programme on natural products, eight oligostilbenes were isolated as active principles from the methanol extract...... of Vitis amurensis. This manuscript reports the isolation, structural elucidation, and anti-viral activities of eight compounds on various neuraminidases from influenza A/PR/8/34 (H1N1), novel swine-origin influenza A (H1N1), and oseltamivir-resistant novel H1N1 (H274Y) expressed in 293T cells...

  18. Rapid detection of the avian influenza virus H5N1 subtype in Egypt ...

    African Journals Online (AJOL)

    The unprecedented spread of highly pathogenic avian influenza virus subtype H5N1 in Egypt ... Effective diagnosis and control management are needed to control the disease. ... Reconstituted clinical samples consisting of H5 AIVs mixed with ...

  19. Broadly-reactive human monoclonal antibodies elicited following pandemic H1N1 influenza virus exposure protect mice from highly pathogenic H5N1 challenge.

    Science.gov (United States)

    Nachbagauer, Raffael; Shore, David; Yang, Hua; Johnson, Scott K; Gabbard, Jon D; Tompkins, S Mark; Wrammert, Jens; Wilson, Patrick C; Stevens, James; Ahmed, Rafi; Krammer, Florian; Ellebedy, Ali H

    2018-06-13

    Broadly cross-reactive antibodies that recognize conserved epitopes within the influenza virus hemagglutinin (HA) stalk domain are of particular interest for their potential use as therapeutic and prophylactic agents against multiple influenza virus subtypes including zoonotic virus strains. Here, we characterized four human HA stalk-reactive monoclonal antibodies (mAbs) for their binding breadth and affinity, in vitro neutralization capacity, and in vivo protective potential against an highly pathogenic avian influenza virus. The monoclonal antibodies were isolated from individuals shortly following infection with (70-1F02 and 1009-3B05) or vaccination against (05-2G02 and 09-3A01) A(H1N1)pdm09. Three of the mAbs bound HAs from multiple strains of group 1 viruses, and one mAb, 05-2G02, bound to both group 1 and group 2 influenza A HAs. All four antibodies prophylactically protected mice against a lethal challenge with the highly pathogenic A/Vietnam/1203/04 (H5N1) strain. Two mAbs, 70-1F02 and 09-3A01, were further tested for their therapeutic efficacy against the same strain and showed good efficacy in this setting as well. One mAb, 70-1F02, was co-crystallized with H5 HA and showed similar heavy chain only interactions as a the previously described anti-stalk antibody CR6261. Finally, we showed that antibodies that compete with these mAbs are prevalent in serum from an individual recently infected with A(H1N1)pdm09 virus. The antibodies described here can be developed into broad-spectrum antiviral therapeutics that could be used to combat infections with zoonotic or emerging pandemic influenza viruses. IMPORTANCE The rise in zoonotic infections of humans with emerging influenza viruses is a worldwide public health concern. The majority of recent zoonotic human influenza cases were caused by H7N9 and H5Nx viruses and were associated with high morbidity and mortality. In addition, seasonal influenza viruses are estimated to cause up to 650,000 deaths annually

  20. Distinct Pathogenesis of Hong Kong-Origin H5N1 Viruses in Mice Compared to That of Other Highly Pathogenic H5 Avian Influenza Viruses

    OpenAIRE

    Dybing, Jody K.; Schultz-Cherry, Stacey; Swayne, David E.; Suarez, David L.; Perdue, Michael L.

    2000-01-01

    In 1997, an outbreak of virulent H5N1 avian influenza virus occurred in poultry in Hong Kong (HK) and was linked to a direct transmission to humans. The factors associated with transmission of avian influenza virus to mammals are not fully understood, and the potential risk of other highly virulent avian influenza A viruses infecting and causing disease in mammals is not known. In this study, two avian and one human HK-origin H5N1 virus along with four additional highly pathogenic H5 avian in...

  1. H1N1 influenza (Swine flu)

    Science.gov (United States)

    Swine flu; H1N1 type A influenza ... The H1N1 virus is now considered a regular flu virus. It is one of the three viruses included in the regular (seasonal) flu vaccine . You cannot get H1N1 flu virus from ...

  2. Unusually High Mortality in Waterfowl Caused by Highly Pathogenic Avian Influenza A(H5N1) in Bangladesh

    Science.gov (United States)

    Haider, N.; Sturm-Ramirez, K.; Khan, S. U.; Rahman, M. Z.; Sarkar, S.; Poh, M. K.; Shivaprasad, H. L.; Kalam, M. A.; Paul, S. K.; Karmakar, P. C.; Balish, A.; Chakraborty, A.; Mamun, A. A.; Mikolon, A. B.; Davis, C. T.; Rahman, M.; Donis, R. O.; Heffelfinger, J. D.; Luby, S. P.; Zeidner, N.

    2015-01-01

    Summary Mortality in ducks and geese caused by highly pathogenic avian influenza A (H5N1) infection had not been previously identified in Bangladesh. In June–July 2011, we investigated mortality in ducks, geese and chickens with suspected H5N1 infection in a north-eastern district of the country to identify the aetiologic agent and extent of the outbreak and identify possible associated human infections. We surveyed households and farms with affected poultry flocks in six villages in Netrokona district and collected cloacal and oropharyngeal swabs from sick birds and tissue samples from dead poultry. We conducted a survey in three of these villages to identify suspected human influenza-like illness cases and collected nasopharyngeal and throat swabs. We tested all swabs by real-time RT-PCR, sequenced cultured viruses, and examined tissue samples by histopathology and immunohistochemistry to detect and characterize influenza virus infection. In the six villages, among the 240 surveyed households and 11 small-scale farms, 61% (1789/2930) of chickens, 47% (4816/10 184) of ducks and 73% (358/493) of geese died within 14 days preceding the investigation. Of 70 sick poultry swabbed, 80% (56/70) had detectable RNA for influenza A/H5, including 89% (49/55) of ducks, 40% (2/5) of geese and 50% (5/10) of chickens. We isolated virus from six of 25 samples; sequence analysis of the hemagglutinin and neuraminidase gene of these six isolates indicated clade 2.3.2.1a of H5N1 virus. Histopathological changes and immunohistochemistry staining of avian influenza viral antigens were recognized in the brain, pancreas and intestines of ducks and chickens. We identified ten human cases showing signs compatible with influenza-like illness; four were positive for influenza A/H3; however, none were positive for influenza A/H5. The recently introduced H5N1 clade 2.3.2.1a virus caused unusually high mortality in ducks and geese. Heightened surveillance in poultry is warranted to guide

  3. Challenge for One Health: Co-Circulation of Zoonotic H5N1 and H9N2 Avian Influenza Viruses in Egypt.

    Science.gov (United States)

    Kim, Shin-Hee

    2018-03-09

    Highly pathogenic avian influenza (HPAI) H5N1 viruses are currently endemic in poultry in Egypt. Eradication of the viruses has been unsuccessful due to improper application of vaccine-based control strategies among other preventive measures. The viruses have evolved rapidly with increased bird-to-human transmission efficacy, thus affecting both animal and public health. Subsequent spread of potentially zoonotic low pathogenic avian influenza (LPAI) H9N2 in poultry has also hindered efficient control of avian influenza. The H5N1 viruses acquired enhanced bird-to-human transmissibility by (1) altering amino acids in hemagglutinin (HA) that enable binding affinity to human-type receptors, (2) loss of the glycosylation site and 130 loop in the HA protein and (3) mutation of E627K in the PB2 protein to enhance viral replication in mammalian hosts. The receptor binding site of HA of Egyptian H9N2 viruses has been shown to contain the Q234L substitution along with a H191 mutation, which can increase human-like receptor specificity. Therefore, co-circulation of H5N1 and H9N2 viruses in poultry farming and live bird markets has increased the risk of human exposure, resulting in complication of the epidemiological situation and raising a concern for potential emergence of a new influenza A virus pandemic. For efficient control of infection and transmission, the efficacy of vaccine and vaccination needs to be improved with a comprehensive control strategy, including enhanced biosecurity, education, surveillance, rapid diagnosis and culling of infected poultry.

  4. Challenge for One Health: Co-Circulation of Zoonotic H5N1 and H9N2 Avian Influenza Viruses in Egypt

    Directory of Open Access Journals (Sweden)

    Shin-Hee Kim

    2018-03-01

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 viruses are currently endemic in poultry in Egypt. Eradication of the viruses has been unsuccessful due to improper application of vaccine-based control strategies among other preventive measures. The viruses have evolved rapidly with increased bird-to-human transmission efficacy, thus affecting both animal and public health. Subsequent spread of potentially zoonotic low pathogenic avian influenza (LPAI H9N2 in poultry has also hindered efficient control of avian influenza. The H5N1 viruses acquired enhanced bird-to-human transmissibility by (1 altering amino acids in hemagglutinin (HA that enable binding affinity to human-type receptors, (2 loss of the glycosylation site and 130 loop in the HA protein and (3 mutation of E627K in the PB2 protein to enhance viral replication in mammalian hosts. The receptor binding site of HA of Egyptian H9N2 viruses has been shown to contain the Q234L substitution along with a H191 mutation, which can increase human-like receptor specificity. Therefore, co-circulation of H5N1 and H9N2 viruses in poultry farming and live bird markets has increased the risk of human exposure, resulting in complication of the epidemiological situation and raising a concern for potential emergence of a new influenza A virus pandemic. For efficient control of infection and transmission, the efficacy of vaccine and vaccination needs to be improved with a comprehensive control strategy, including enhanced biosecurity, education, surveillance, rapid diagnosis and culling of infected poultry.

  5. Comparing introduction to Europe of highly pathogenic avian influenza viruses A(H5N8) in 2014 and A(H5N1) in 2005

    NARCIS (Netherlands)

    Adlhoch, C.; Gossner, C.; Koch, G.; Brown, I.; Bouwstra, R.J.; Verdonck, F.; Penttinen, P.; Harder, T.

    2014-01-01

    Since the beginning of November 2014, nine outbreaks of highly pathogenic avian influenza virus (HPAIV) A(H5N8) in poultry have been detected in four European countries. In this report, similarities and differences between the modes of introduction of HPAIV A(H5N1) and A(H5N8) into Europe are

  6. Pandemic influenza--including a risk assessment of H5N1.

    Science.gov (United States)

    Taubenberger, J K; Morens, D M

    2009-04-01

    Influenza pandemics and epidemics have apparently occurred since at least the Middle Ages. When pandemics appear, 50% or more of an affected population can be infected in a single year, and the number of deaths caused by influenza can dramatically exceed what is normally expected. Since 1500, there appear to have been 13 or more influenza pandemics. In the past 120 years there were undoubted pandemics in 1889, 1918, 1957, 1968, and 1977. Although most experts believe we will face another influenza pandemic, it is impossible to predict when it will appear, where it will originate, or how severe it will be. Nor is there agreement about the subtype of influenza virus most likely to cause the next pandemic. The continuing spread of H5N1 highly pathogenic avian influenza viruses has heightened interest in pandemic prediction. Despite uncertainties in the historical record of the pre-virology era, study of previous pandemics may help guide future pandemic planning and lead to a better understanding of the complex ecobiology underlying the formation of pandemic strains of influenza A viruses.

  7. Human mesenchymal stromal cells reduce influenza A H5N1-associated acute lung injury in vitro and in vivo.

    Science.gov (United States)

    Chan, Michael C W; Kuok, Denise I T; Leung, Connie Y H; Hui, Kenrie P Y; Valkenburg, Sophie A; Lau, Eric H Y; Nicholls, John M; Fang, Xiaohui; Guan, Yi; Lee, Jae W; Chan, Renee W Y; Webster, Robert G; Matthay, Michael A; Peiris, J S Malik

    2016-03-29

    Influenza can cause acute lung injury. Because immune responses often play a role, antivirals may not ensure a successful outcome. To identify pathogenic mechanisms and potential adjunctive therapeutic options, we compared the extent to which avian influenza A/H5N1 virus and seasonal influenza A/H1N1 virus impair alveolar fluid clearance and protein permeability in an in vitro model of acute lung injury, defined the role of virus-induced soluble mediators in these injury effects, and demonstrated that the effects are prevented or reduced by bone marrow-derived multipotent mesenchymal stromal cells. We verified the in vivo relevance of these findings in mice experimentally infected with influenza A/H5N1. We found that, in vitro, the alveolar epithelium's protein permeability and fluid clearance were dysregulated by soluble immune mediators released upon infection with avian (A/Hong Kong/483/97, H5N1) but not seasonal (A/Hong Kong/54/98, H1N1) influenza virus. The reduced alveolar fluid transport associated with down-regulation of sodium and chloride transporters was prevented or reduced by coculture with mesenchymal stromal cells. In vivo, treatment of aged H5N1-infected mice with mesenchymal stromal cells increased their likelihood of survival. We conclude that mesenchymal stromal cells significantly reduce the impairment of alveolar fluid clearance induced by A/H5N1 infection in vitro and prevent or reduce A/H5N1-associated acute lung injury in vivo. This potential adjunctive therapy for severe influenza-induced lung disease warrants rapid clinical investigation.

  8. Induction of protective immunity against H1N1 influenza A(H1N1)pdm09 with spray-dried and electron-beam sterilised vaccines in non-human primates.

    Science.gov (United States)

    Scherließ, Regina; Ajmera, Ankur; Dennis, Mike; Carroll, Miles W; Altrichter, Jens; Silman, Nigel J; Scholz, Martin; Kemter, Kristina; Marriott, Anthony C

    2014-04-17

    Currently, the need for cooled storage and the impossibility of terminal sterilisation are major drawbacks in vaccine manufacturing and distribution. To overcome current restrictions a preclinical safety and efficacy study was conducted to evaluate new influenza A vaccine formulations regarding thermal resistance, resistance against irradiation-mediated damage and storage stability. We evaluated the efficacy of novel antigen stabilizing and protecting solutions (SPS) to protect influenza A(H1N1)pdm09 split virus antigen under experimental conditions in vitro and in vivo. Original or SPS re-buffered vaccine (Pandemrix) was spray-dried and terminally sterilised by irradiation with 25 kGy (e-beam). Antigen integrity was monitored by SDS-PAGE, dynamic light scattering, size exclusion chromatography and functional haemagglutination assays. In vitro screening experiments revealed a number of highly stable compositions containing glycyrrhizinic acid (GA) and/or chitosan. The most stable composition was selected for storage tests and in vivo assessment of seroconversion in non-human primates (Macaca fascicularis) using a prime-boost strategy. Redispersed formulations with original adjuvant were administered intramuscularly. Storage data revealed high stability of protected vaccines at 4°C and 25°C, 60% relative humidity, for at least three months. Animals receiving original Pandemrix exhibited expected levels of seroconversion after 21 days (prime) and 48 days (boost) as assessed by haemagglutination inhibition and microneutralisation assays. Animals vaccinated with spray-dried and irradiated Pandemrix failed to exhibit seroconversion after 21 days whereas spray-dried and irradiated, SPS-protected vaccines elicited similar seroconversion levels to those vaccinated with original Pandemrix. Boost immunisation with SPS-protected vaccine resulted in a strong increase in seroconversion but had only minor effects in animals treated with non SPS-protected vaccine. In conclusion

  9. Outbreak of pandemic influenza A/H1N1 2009 in Nepal.

    Science.gov (United States)

    Adhikari, Bal Ram; Shakya, Geeta; Upadhyay, Bishnu Prasad; Prakash Kc, Khagendra; Shrestha, Sirjana Devi; Dhungana, Guna Raj

    2011-03-23

    The 2009 flu pandemic is a global outbreak of a new strain of H1N1 influenza virus. Pandemic influenza A (H1N1) 2009 has posed a serious public health challenge world-wide. Nepal has started Laboratory diagnosis of Pandemic influenza A/H1N1 from mid June 2009 though active screening of febrile travellers with respiratory symptoms was started from April 27, 2009. Out of 609 collected samples, 302 (49.6%) were Universal Influenza A positive. Among the influenza A positive samples, 172(28.3%) were positive for Pandemic influenza A/H1N1 and 130 (21.3%) were Seasonal influenza A. Most of the pandemic cases (53%) were found among young people with ≤ 20 years. Case Fatality Ratio for Pandemic influenza A/H1N1 in Nepal was 1.74%. Upon Molecular characterization, all the isolated pandemic influenza A/H1N1 2009 virus found in Nepal were antigenically and genetically related to the novel influenza A/CALIFORNIA/07/2009-LIKE (H1N1)v type. The Pandemic 2009 influenza virus found in Nepal were antigenically and genetically related to the novel A/CALIFORNIA/07/2009-LIKE (H1N1)v type.

  10. Outbreak of pandemic influenza A/H1N1 2009 in Nepal

    Directory of Open Access Journals (Sweden)

    Shrestha Sirjana

    2011-03-01

    Full Text Available Abstract Background The 2009 flu pandemic is a global outbreak of a new strain of H1N1 influenza virus. Pandemic influenza A (H1N1 2009 has posed a serious public health challenge world-wide. Nepal has started Laboratory diagnosis of Pandemic influenza A/H1N1 from mid June 2009 though active screening of febrile travellers with respiratory symptoms was started from April 27, 2009. Results Out of 609 collected samples, 302 (49.6% were Universal Influenza A positive. Among the influenza A positive samples, 172(28.3% were positive for Pandemic influenza A/H1N1 and 130 (21.3% were Seasonal influenza A. Most of the pandemic cases (53% were found among young people with ≤ 20 years. Case Fatality Ratio for Pandemic influenza A/H1N1 in Nepal was 1.74%. Upon Molecular characterization, all the isolated pandemic influenza A/H1N1 2009 virus found in Nepal were antigenically and genetically related to the novel influenza A/CALIFORNIA/07/2009-LIKE (H1N1v type. Conclusion The Pandemic 2009 influenza virus found in Nepal were antigenically and genetically related to the novel A/CALIFORNIA/07/2009-LIKE (H1N1v type.

  11. Protection of chickens against H5N1 highly pathogenic avian influenza virus infection by live vaccination with infectious laryngotracheitis virus recombinants expressing H5 hemagglutinin and N1 neuraminidase.

    Science.gov (United States)

    Pavlova, Sophia P; Veits, Jutta; Keil, Günther M; Mettenleiter, Thomas C; Fuchs, Walter

    2009-01-29

    Attenuated vaccine strains of the alphaherpesvirus causing infectious laryngotracheitis of chickens (ILTV, gallid herpesvirus 1) can be used for mass application. Previously, we showed that live virus vaccination with recombinant ILTV expressing hemagglutinin of highly pathogenic avian influenza viruses (HPAIV) protected chickens against ILT and fowl plague caused by HPAIV carrying the corresponding hemagglutinin subtypes [Lüschow D, Werner O, Mettenleiter TC, Fuchs W. Protection of chickens from lethal avian influenza A virus infection by live-virus vaccination with infectious laryngotracheitis virus recombinants expressing the hemagglutinin (H5) gene. Vaccine 2001;19(30):4249-59; Veits J, Lüschow D, Kindermann K, Werner O, Teifke JP, Mettenleiter TC, et al. Deletion of the non-essential UL0 gene of infectious laryngotracheitis (ILT) virus leads to attenuation in chickens, and UL0 mutants expressing influenza virus haemagglutinin (H7) protect against ILT and fowl plague. J Gen Virol 2003;84(12):3343-52]. However, protection against H5N1 HPAIV was not satisfactory. Therefore, a newly designed dUTPase-negative ILTV vector was used for rapid insertion of the H5-hemagglutinin, or N1-neuraminidase genes of a recent H5N1 HPAIV isolate. Compared to our previous constructs, protein expression was considerably enhanced by insertion of synthetic introns downstream of the human cytomegalovirus immediate-early promoter within the 5'-nontranslated region of the transgenes. Deletion of the viral dUTPase gene did not affect in vitro replication of the ILTV recombinants, but led to sufficient attenuation in vivo. After a single ocular immunization, all chickens developed H5- or N1-specific serum antibodies. Nevertheless, animals immunized with N1-ILTV died after subsequent H5N1 HPAIV challenge, although survival times were prolonged compared to non-vaccinated controls. In contrast, all chickens vaccinated with either H5-ILTV alone, or H5- and N1-ILTV simultaneously, survived

  12. Using knowledge fusion to analyze avian influenza H5N1 in East and Southeast Asia.

    Directory of Open Access Journals (Sweden)

    Erjia Ge

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1, a disease associated with high rates of mortality in infected human populations, poses a serious threat to public health in many parts of the world. This article reports findings from a study aimed at improving our understanding of the spatial pattern of the highly pathogenic avian influenza, H5N1, risk in East-Southeast Asia where the disease is both persistent and devastating. Though many disciplines have made important contributions to our understanding of H5N1, it remains a challenge to integrate knowledge from different disciplines. This study applies genetic analysis that identifies the evolution of the H5N1 virus in space and time, epidemiological analysis that determines socio-ecological factors associated with H5N1 occurrence, and statistical analysis that identifies outbreak clusters, and then applies a methodology to formally integrate the findings of the three sets of methodologies. The present study is novel in two respects. First it makes the initiative attempt to use genetic sequences and space-time data to create a space-time phylogenetic tree to estimate and map the virus' ability to spread. Second, by integrating the results we are able to generate insights into the space-time occurrence and spread of H5N1 that we believe have a higher level of corroboration than is possible when analysis is based on only one methodology. Our research identifies links between the occurrence of H5N1 by area and a set of socio-ecological factors including altitude, population density, poultry density, and the shortest path distances to inland water, coastlines, migrating routes, railways, and roads. This study seeks to lay a solid foundation for the interdisciplinary study of this and other influenza outbreaks. It will provide substantive information for containing H5N1 outbreaks.

  13. Using knowledge fusion to analyze avian influenza H5N1 in East and Southeast Asia.

    Science.gov (United States)

    Ge, Erjia; Haining, Robert; Li, Chi Pang; Yu, Zuguo; Waye, Miu Yee; Chu, Ka Hou; Leung, Yee

    2012-01-01

    Highly pathogenic avian influenza (HPAI) H5N1, a disease associated with high rates of mortality in infected human populations, poses a serious threat to public health in many parts of the world. This article reports findings from a study aimed at improving our understanding of the spatial pattern of the highly pathogenic avian influenza, H5N1, risk in East-Southeast Asia where the disease is both persistent and devastating. Though many disciplines have made important contributions to our understanding of H5N1, it remains a challenge to integrate knowledge from different disciplines. This study applies genetic analysis that identifies the evolution of the H5N1 virus in space and time, epidemiological analysis that determines socio-ecological factors associated with H5N1 occurrence, and statistical analysis that identifies outbreak clusters, and then applies a methodology to formally integrate the findings of the three sets of methodologies. The present study is novel in two respects. First it makes the initiative attempt to use genetic sequences and space-time data to create a space-time phylogenetic tree to estimate and map the virus' ability to spread. Second, by integrating the results we are able to generate insights into the space-time occurrence and spread of H5N1 that we believe have a higher level of corroboration than is possible when analysis is based on only one methodology. Our research identifies links between the occurrence of H5N1 by area and a set of socio-ecological factors including altitude, population density, poultry density, and the shortest path distances to inland water, coastlines, migrating routes, railways, and roads. This study seeks to lay a solid foundation for the interdisciplinary study of this and other influenza outbreaks. It will provide substantive information for containing H5N1 outbreaks.

  14. H7N9 and H5N1 avian influenza suitability models for China: accounting for new poultry and live-poultry markets distribution data.

    Science.gov (United States)

    Artois, Jean; Lai, Shengjie; Feng, Luzhao; Jiang, Hui; Zhou, Hang; Li, Xiangping; Dhingra, Madhur S; Linard, Catherine; Nicolas, Gaëlle; Xiao, Xiangming; Robinson, Timothy P; Yu, Hongjie; Gilbert, Marius

    2017-01-01

    In the last two decades, two important avian influenza viruses infecting humans emerged in China, the highly pathogenic avian influenza (HPAI) H5N1 virus in the late nineties, and the low pathogenic avian influenza (LPAI) H7N9 virus in 2013. China is home to the largest population of chickens (4.83 billion) and ducks (0.694 billion), representing, respectively 23.1 and 58.6% of the 2013 world stock, with a significant part of poultry sold through live-poultry markets potentially contributing to the spread of avian influenza viruses. Previous models have looked at factors associated with HPAI H5N1 in poultry and LPAI H7N9 in markets. However, these have not been studied and compared with a consistent set of predictor variables. Significant progress was recently made in the collection of poultry census and live-poultry market data, which are key potential factors in the distribution of both diseases. Here we compiled and reprocessed a new set of poultry census data and used these to analyse HPAI H5N1 and LPAI H7N9 distributions with boosted regression trees models. We found a limited impact of the improved poultry layers compared to models based on previous poultry census data, and a positive and previously unreported association between HPAI H5N1 outbreaks and the density of live-poultry markets. In addition, the models fitted for the HPAI H5N1 and LPAI H7N9 viruses predict a high risk of disease presence for the area around Shanghai and Hong Kong. The main difference in prediction between the two viruses concerned the suitability of HPAI H5N1 in north-China around the Yellow sea (outlined with Tianjin, Beijing, and Shenyang city) where LPAI H7N9 has not spread intensely.

  15. Unusually High Mortality in Waterfowl Caused by Highly Pathogenic Avian Influenza A(H5N1) in Bangladesh

    DEFF Research Database (Denmark)

    Haider, Najmul; Sturm-Ramirez, K.; Khan, S. U.

    2017-01-01

    a survey in three of these villages to identify suspected human influenza-like illness cases and collected nasopharyngeal and throat swabs. We tested all swabs by real-time RT-PCR, sequenced cultured viruses, and examined tissue samples by histopathology and immunohistochemistry to detect and characterize...... and immunohistochemistry staining of avian influenza viral antigens were recognized in the brain, pancreas and intestines of ducks and chickens. We identified ten human cases showing signs compatible with influenza-like illness; four were positive for influenza A/H3; however, none were positive for influenza A/H5......Mortality in ducks and geese caused by highly pathogenic avian influenza A(H5N1) infection had not been previously identified in Bangladesh. In June-July 2011, we investigated mortality in ducks, geese and chickens with suspected H5N1 infection in a north-eastern district of the country to identify...

  16. Live, Attenuated Influenza A H5N1 Candidate Vaccines Provide Broad Cross-Protection in Mice and Ferrets

    Science.gov (United States)

    Mills, Kimberly L; Jin, Hong; Duke, Greg; Lu, Bin; Luke, Catherine J; Murphy, Brian; Swayne, David E; Kemble, George; Subbarao, Kanta

    2006-01-01

    Background Recent outbreaks of highly pathogenic influenza A H5N1 viruses in humans and avian species that began in Asia and have spread to other continents underscore an urgent need to develop vaccines that would protect the human population in the event of a pandemic. Methods and Findings Live, attenuated candidate vaccines possessing genes encoding a modified H5 hemagglutinin (HA) and a wild-type (wt) N1 neuraminidase from influenza A H5N1 viruses isolated in Hong Kong and Vietnam in 1997, 2003, and 2004, and remaining gene segments derived from the cold-adapted (ca) influenza A vaccine donor strain, influenza A/Ann Arbor/6/60 ca (H2N2), were generated by reverse genetics. The H5N1 ca vaccine viruses required trypsin for efficient growth in vitro, as predicted by the modification engineered in the gene encoding the HA, and possessed the temperature-sensitive and attenuation phenotypes specified by the internal protein genes of the ca vaccine donor strain. More importantly, the candidate vaccines were immunogenic in mice. Four weeks after receiving a single dose of 106 50% tissue culture infectious doses of intranasally administered vaccines, mice were fully protected from lethality following challenge with homologous and antigenically distinct heterologous wt H5N1 viruses from different genetic sublineages (clades 1, 2, and 3) that were isolated in Asia between 1997 and 2005. Four weeks after receiving two doses of the vaccines, mice and ferrets were fully protected against pulmonary replication of homologous and heterologous wt H5N1 viruses. Conclusions The promising findings in these preclinical studies of safety, immunogenicity, and efficacy of the H5N1 ca vaccines against antigenically diverse H5N1 vaccines provide support for their careful evaluation in Phase 1 clinical trials in humans. PMID:16968127

  17. Live, attenuated influenza A H5N1 candidate vaccines provide broad cross-protection in mice and ferrets.

    Directory of Open Access Journals (Sweden)

    Amorsolo L Suguitan

    2006-09-01

    Full Text Available Recent outbreaks of highly pathogenic influenza A H5N1 viruses in humans and avian species that began in Asia and have spread to other continents underscore an urgent need to develop vaccines that would protect the human population in the event of a pandemic.Live, attenuated candidate vaccines possessing genes encoding a modified H5 hemagglutinin (HA and a wild-type (wt N1 neuraminidase from influenza A H5N1 viruses isolated in Hong Kong and Vietnam in 1997, 2003, and 2004, and remaining gene segments derived from the cold-adapted (ca influenza A vaccine donor strain, influenza A/Ann Arbor/6/60 ca (H2N2, were generated by reverse genetics. The H5N1 ca vaccine viruses required trypsin for efficient growth in vitro, as predicted by the modification engineered in the gene encoding the HA, and possessed the temperature-sensitive and attenuation phenotypes specified by the internal protein genes of the ca vaccine donor strain. More importantly, the candidate vaccines were immunogenic in mice. Four weeks after receiving a single dose of 10(6 50% tissue culture infectious doses of intranasally administered vaccines, mice were fully protected from lethality following challenge with homologous and antigenically distinct heterologous wt H5N1 viruses from different genetic sublineages (clades 1, 2, and 3 that were isolated in Asia between 1997 and 2005. Four weeks after receiving two doses of the vaccines, mice and ferrets were fully protected against pulmonary replication of homologous and heterologous wt H5N1 viruses.The promising findings in these preclinical studies of safety, immunogenicity, and efficacy of the H5N1 ca vaccines against antigenically diverse H5N1 vaccines provide support for their careful evaluation in Phase 1 clinical trials in humans.

  18. Characteristics of atopic children with pandemic H1N1 influenza viral infection: pandemic H1N1 influenza reveals 'occult' asthma of childhood.

    Science.gov (United States)

    Hasegawa, Shunji; Hirano, Reiji; Hashimoto, Kunio; Haneda, Yasuhiro; Shirabe, Komei; Ichiyama, Takashi

    2011-02-01

    The number of human cases of pandemic H1N1 influenza viral infection has increased in Japan since April 2009, as it has worldwide. This virus is widespread in the Yamaguchi prefecture in western Japan, where most infected children exhibited respiratory symptoms. Bronchial asthma is thought to be one of the risk factors that exacerbate respiratory symptoms of pandemic H1N1-infected patients, but the pathogenesis remains unclear. We retrospectively investigated the records of 33 children with pandemic H1N1 influenza viral infection who were admitted to our hospital between October and December 2009 and analyzed their clinical features. The percentage of children with asthma attack, with or without abnormal findings on chest radiographs (pneumonia, atelectasis, etc.), caused by pandemic H1N1 influenza infection was significantly higher than that of children with asthma attack and 2008-2009 seasonal influenza infection. Of the 33 children in our study, 22 (66.7%) experienced an asthma attack. Among these children, 20 (90.9%) did not receive long-term management for bronchial asthma, whereas 7 (31.8%) were not diagnosed with bronchial asthma and had experienced their first asthma attack. However, the severity of the attack did not correlate with the severity of the pulmonary complications of pandemic H1N1 influenza viral infection. The pandemic H1N1 influenza virus greatly increases the risk of lower respiratory tract complications such as asthma attack, pneumonia, and atelectasis, when compared to the seasonal influenza virus. Furthermore, our results suggest that pandemic H1N1 influenza viral infection can easily induce a severe asthma attack, pneumonia, and atelectasis in atopic children without any history of either an asthma attack or asthma treatment. © 2011 John Wiley & Sons A/S.

  19. Unusually High Mortality in Waterfowl Caused by Highly Pathogenic Avian Influenza A(H5N1) in Bangladesh.

    Science.gov (United States)

    Haider, N; Sturm-Ramirez, K; Khan, S U; Rahman, M Z; Sarkar, S; Poh, M K; Shivaprasad, H L; Kalam, M A; Paul, S K; Karmakar, P C; Balish, A; Chakraborty, A; Mamun, A A; Mikolon, A B; Davis, C T; Rahman, M; Donis, R O; Heffelfinger, J D; Luby, S P; Zeidner, N

    2017-02-01

    Mortality in ducks and geese caused by highly pathogenic avian influenza A(H5N1) infection had not been previously identified in Bangladesh. In June-July 2011, we investigated mortality in ducks, geese and chickens with suspected H5N1 infection in a north-eastern district of the country to identify the aetiologic agent and extent of the outbreak and identify possible associated human infections. We surveyed households and farms with affected poultry flocks in six villages in Netrokona district and collected cloacal and oropharyngeal swabs from sick birds and tissue samples from dead poultry. We conducted a survey in three of these villages to identify suspected human influenza-like illness cases and collected nasopharyngeal and throat swabs. We tested all swabs by real-time RT-PCR, sequenced cultured viruses, and examined tissue samples by histopathology and immunohistochemistry to detect and characterize influenza virus infection. In the six villages, among the 240 surveyed households and 11 small-scale farms, 61% (1789/2930) of chickens, 47% (4816/10 184) of ducks and 73% (358/493) of geese died within 14 days preceding the investigation. Of 70 sick poultry swabbed, 80% (56/70) had detectable RNA for influenza A/H5, including 89% (49/55) of ducks, 40% (2/5) of geese and 50% (5/10) of chickens. We isolated virus from six of 25 samples; sequence analysis of the hemagglutinin and neuraminidase gene of these six isolates indicated clade 2.3.2.1a of H5N1 virus. Histopathological changes and immunohistochemistry staining of avian influenza viral antigens were recognized in the brain, pancreas and intestines of ducks and chickens. We identified ten human cases showing signs compatible with influenza-like illness; four were positive for influenza A/H3; however, none were positive for influenza A/H5. The recently introduced H5N1 clade 2.3.2.1a virus caused unusually high mortality in ducks and geese. Heightened surveillance in poultry is warranted to guide appropriate

  20. Risk of influenza A (H5N1) infection among poultry workers, Hong Kong, 1997-1998.

    Science.gov (United States)

    Bridges, Carolyn Buxton; Lim, Wilina; Hu-Primmer, Jean; Sims, Les; Fukuda, Keiji; Mak, K H; Rowe, Thomas; Thompson, William W; Conn, Laura; Lu, Xiuhua; Cox, Nancy J; Katz, Jacqueline M

    2002-04-15

    In 1997, outbreaks of highly pathogenic influenza A (H5N1) among poultry coincided with 18 documented human cases of H5N1 illness. Although exposure to live poultry was associated with human illness, no cases were documented among poultry workers (PWs). To evaluate the potential for avian-to-human transmission of H5N1, a cohort study was conducted among 293 Hong Kong government workers (GWs) who participated in a poultry culling operation and among 1525 PWs. Paired serum samples collected from GWs and single serum samples collected from PWs were considered to be anti-H5 antibody positive if they were positive by both microneutralization and Western blot testing. Among GWs, 3% were seropositive, and 1 seroconversion was documented. Among PWs, approximately 10% had anti-H5 antibody. More-intensive poultry exposure, such as butchering and exposure to ill poultry, was associated with having anti-H5 antibody. These findings suggest an increased risk for avian influenza infection from occupational exposure.

  1. A Meta-Analysis of the Prevalence of Influenza A H5N1 and H7N9 Infection in Birds.

    Science.gov (United States)

    Bui, C; Rahman, B; Heywood, A E; MacIntyre, C R

    2017-06-01

    Despite a much higher rate of human influenza A (H7N9) infection compared to influenza A (H5N1), and the assumption that birds are the source of human infection, detection rates of H7N9 in birds are lower than those of H5N1. This raises a question about the role of birds in the spread and transmission of H7N9 to humans. We conducted a meta-analysis of overall prevalence of H5N1 and H7N9 in different bird populations (domestic poultry, wild birds) and different environments (live bird markets, commercial poultry farms, wild habitats). The electronic database, Scopus, was searched for published papers, and Google was searched for country surveillance reports. A random effect meta-analysis model was used to produce pooled estimates of the prevalence of H5N1 and H7N9 for various subcategories. A random effects logistic regression model was used to compare prevalence rates between H5N1 and H7N9. Both viruses have low prevalence across all bird populations. Significant differences in prevalence rates were observed in domestic birds, farm settings, for pathogen and antibody testing, and during routine surveillance. Random effects logistic regression analyses show that among domestic birds, the prevalence of H5N1 is 47.48 (95% CI: 17.15-133.13, P bird outbreaks), the prevalence of H5N1 is still higher than H7N9 with an OR of 43.02 (95% CI: 16.60-111.53, P birds are postulated to be the source. Much lower rates of H7N9 in birds compared to H5N1 raise doubts about birds as the sole source of high rates of human H7N9 infection. Other sources of transmission of H7N9 need to be considered and explored. © 2016 The Authors. Transboundary and Emerging Diseases Published by Blackwell Verlag GmbH.

  2. Avian Influenza Virus A (H5N1), Detected through Routine Surveillance, in Child, Bangladesh

    Science.gov (United States)

    Alamgir, A.S.M.; Sultana, Rebecca; Islam, M. Saiful; Rahman, Mustafizur; Fry, Alicia M.; Shu, Bo; Lindstrom, Stephen; Nahar, Kamrun; Goswami, Doli; Haider, M. Sabbir; Nahar, Sharifun; Butler, Ebonee; Hancock, Kathy; Donis, Ruben O.; Davis, Charles T.; Zaman, Rashid Uz; Luby, Stephen P.; Uyeki, Timothy M.; Rahman, Mahmudur

    2009-01-01

    We identified avian influenza virus A (H5N1) infection in a child in Bangladesh in 2008 by routine influenza surveillance. The virus was of the same clade and phylogenetic subgroup as that circulating among poultry during the period. This case illustrates the value of routine surveillance for detection of novel influenza virus. PMID:19751601

  3. Reduced experimental infectivity and transmissibility of intercontinental H5 (H5N8 and H5N2) compared to Eurasian H5N1 highly pathogenic avian influenza viruses for chickens, turkeys, and Japanese quail

    Science.gov (United States)

    H5N1 high pathogenicity avian influenza (HPAI) virus (HPAIV) emerged in 1996 in Guangdong China and has since spread to infect and cause deaths in wild birds, poultry and humans in over 63 countries in Asia, Europe and Africa; and more recently a reassortant H5N8 clade 2.3.4.4 HPAI virus has spread ...

  4. [Influenza A/H5N1 virus outbreaks and prepardness to avert flu pandemic].

    Science.gov (United States)

    Haque, A; Lucas, B; Hober, D

    2007-01-01

    This review emphasizes the need to improve the knowledge of the biology of H5N1 virus, a candidate for causing the next influenza pandemic. In-depth knowledge of mode of infection, mechanisms of pathogenesis and immune response will help in devising an efficient and practical control strategy against this flu virus. We have discussed limitations of currently available vaccines and proposed novel approaches for making better vaccines against H5N1 influenza virus. They include cell-culture system, reverse genetics, adjuvant development. Our review has also underscored the concept of therapeutic vaccine (anti-disease vaccine), which is aimed at diminishing 'cytokine storm' seen in acute respiratory distress syndrome and/or hemophagocytosis.

  5. Characterizing wild bird contact and seropositivity to highly pathogenic avian influenza A (H5N1) virus in Alaskan residents.

    Science.gov (United States)

    Reed, Carrie; Bruden, Dana; Byrd, Kathy K; Veguilla, Vic; Bruce, Michael; Hurlburt, Debby; Wang, David; Holiday, Crystal; Hancock, Kathy; Ortiz, Justin R; Klejka, Joe; Katz, Jacqueline M; Uyeki, Timothy M

    2014-09-01

    Highly pathogenic avian influenza A (HPAI) H5N1 viruses have infected poultry and wild birds on three continents with more than 600 reported human cases (59% mortality) since 2003. Wild aquatic birds are the natural reservoir for avian influenza A viruses, and migratory birds have been documented with HPAI H5N1 virus infection. Since 2005, clade 2.2 HPAI H5N1 viruses have spread from Asia to many countries. We conducted a cross-sectional seroepidemiological survey in Anchorage and western Alaska to identify possible behaviors associated with migratory bird exposure and measure seropositivity to HPAI H5N1. We enrolled rural subsistence bird hunters and their families, urban sport hunters, wildlife biologists, and a comparison group without bird contact. We interviewed participants regarding their exposures to wild birds and collected blood to perform serologic testing for antibodies against a clade 2.2 HPAI H5N1 virus strain. Hunters and wildlife biologists reported exposures to wild migratory birds that may confer risk of infection with avian influenza A viruses, although none of the 916 participants had evidence of seropositivity to HPAI H5N1. We characterized wild bird contact among Alaskans and behaviors that may influence risk of infection with avian influenza A viruses. Such knowledge can inform surveillance and risk communication surrounding HPAI H5N1 and other influenza viruses in a population with exposure to wild birds at a crossroads of intercontinental migratory flyways. © 2014 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

  6. Prophylactic and therapeutic efficacy of human monoclonal antibodies against H5N1 influenza.

    Directory of Open Access Journals (Sweden)

    Cameron P Simmons

    2007-05-01

    Full Text Available New prophylactic and therapeutic strategies to combat human infections with highly pathogenic avian influenza (HPAI H5N1 viruses are needed. We generated neutralizing anti-H5N1 human monoclonal antibodies (mAbs and tested their efficacy for prophylaxis and therapy in a murine model of infection.Using Epstein-Barr virus we immortalized memory B cells from Vietnamese adults who had recovered from infections with HPAI H5N1 viruses. Supernatants from B cell lines were screened in a virus neutralization assay. B cell lines secreting neutralizing antibodies were cloned and the mAbs purified. The cross-reactivity of these antibodies for different strains of H5N1 was tested in vitro by neutralization assays, and their prophylactic and therapeutic efficacy in vivo was tested in mice. In vitro, mAbs FLA3.14 and FLD20.19 neutralized both Clade I and Clade II H5N1 viruses, whilst FLA5.10 and FLD21.140 neutralized Clade I viruses only. In vivo, FLA3.14 and FLA5.10 conferred protection from lethality in mice challenged with A/Vietnam/1203/04 (H5N1 in a dose-dependent manner. mAb prophylaxis provided a statistically significant reduction in pulmonary virus titer, reduced associated inflammation in the lungs, and restricted extrapulmonary dissemination of the virus. Therapeutic doses of FLA3.14, FLA5.10, FLD20.19, and FLD21.140 provided robust protection from lethality at least up to 72 h postinfection with A/Vietnam/1203/04 (H5N1. mAbs FLA3.14, FLD21.140 and FLD20.19, but not FLA5.10, were also therapeutically active in vivo against the Clade II virus A/Indonesia/5/2005 (H5N1.These studies provide proof of concept that fully human mAbs with neutralizing activity can be rapidly generated from the peripheral blood of convalescent patients and that these mAbs are effective for the prevention and treatment of H5N1 infection in a mouse model. A panel of neutralizing, cross-reactive mAbs might be useful for prophylaxis or adjunctive treatment of human cases of H5N1

  7. Comparing introduction to Europe of highly pathogenic avian influenza viruses A(H5N8) in 2014 and A(H5N1) in 2005.

    Science.gov (United States)

    Adlhoch, C; Gossner, C; Koch, G; Brown, I; Bouwstra, R; Verdonck, F; Penttinen, P; Harder, T

    2014-12-18

    Since the beginning of November 2014, nine outbreaks of highly pathogenic avian influenza virus (HPAIV) A(H5N8) in poultry have been detected in four European countries. In this report, similarities and differences between the modes of introduction of HPAIV A(H5N1) and A(H5N8) into Europe are described. Experiences from outbreaks of A(H5N1) in Europe demonstrated that early detection to control HPAIV in poultry has proven pivotal to minimise the risk of zoonotic transmission and prevention of human cases.

  8. CD206+ Cell Number Differentiates Influenza A (H1N1pdm09 from Seasonal Influenza A Virus in Fatal Cases

    Directory of Open Access Journals (Sweden)

    Heidi G. Rodriguez-Ramirez

    2014-01-01

    Full Text Available In 2009, a new influenza A (H1N1 virus affected many persons around the world. There is an urgent need for finding biomarkers to distinguish between influenza A (H1N1pdm09 and seasonal influenza virus. We investigated these possible biomarkers in the lung of fatal cases of confirmed influenza A (H1N1pdm09. Cytokines (inflammatory and anti-inflammatory and cellular markers (macrophages and lymphocytes subpopulation markers were analyzed in lung tissue from both influenza A (H1N1pdm09 and seasonal influenza virus. High levels of IL-17, IFN-γ, and TNF-α positive cells were identical in lung tissue from the influenza A (H1N1pdm09 and seasonal cases when compared with healthy lung tissue (P<0.05. Increased IL-4+ cells, and CD4+ and CD14+ cells were also found in high levels in both influenza A (H1N1pdm09 and seasonal influenza virus (P<0.05. Low levels of CD206+ cells (marker of alternatively activated macrophages marker in lung were found in influenza A (H1N1pdm09 when compared with seasonal influenza virus (P<0.05, and the ratio of CD206/CD14+ cells was 2.5-fold higher in seasonal and noninfluenza group compared with influenza A (H1N1pdm09 (P<0.05. In conclusion, CD206+ cells differentiate between influenza A (H1N1pdm09 and seasonal influenza virus in lung tissue of fatal cases.

  9. Fluorescence biosensor based on CdTe quantum dots for specific detection of H5N1 avian influenza virus

    Science.gov (United States)

    Hoa Nguyen, Thi; Dieu Thuy Ung, Thi; Hien Vu, Thi; Tran, Thi Kim Chi; Quyen Dong, Van; Khang Dinh, Duy; Liem Nguyen, Quang

    2012-09-01

    This report highlights the fabrication of fluorescence biosensors based on CdTe quantum dots (QDs) for specific detection of H5N1 avian influenza virus. The core biosensor was composed of (i) the highly luminescent CdTe/CdS QDs, (ii) chromatophores extracted from bacteria Rhodospirillum rubrum, and (iii) the antibody of β-subunit. This core part was linked to the peripheral part of the biosensor via a biotin-streptavidin-biotin bridge and finally connected to the H5N1 antibody to make it ready for detecting H5N1 avian influenza virus. Detailed studies of each constituent were performed showing the image of QDs-labeled chromatophores under optical microscope, proper photoluminescence (PL) spectra of CdTe/CdS QDs, chromatophores and the H5N1 avian influenza viruses.

  10. Highly pathogenic avian influenza virus subtype H5N1 in mute swans (Cygnus olor) in Central Bosnia.

    Science.gov (United States)

    Goletić, Teufik; Gagić, Abdulah; Residbegović, Emina; Kustura, Aida; Kavazović, Aida; Savić, Vladimir; Harder, Timm; Starick, Elke; Prasović, Senad

    2010-03-01

    In order to determine the actual prevalence of avian influenza viruses (AIVs) in wild birds in Bosnia and Herzegovina, extensive surveillance was carried out between October 2005 and April 2006. A total of 394 samples representing 41 bird species were examined for the presence of influenza A virus using virus isolation in embryonated chicken eggs, PCR, and nucleotide sequencing. AIV subtype H5N1 was detected in two mute swans (Cygnus olor). The isolates were determined to be highly pathogenic avian influenza (HPAI) virus and the hemagglutinin sequence was closely similar to A/Cygnus olor/Astrakhan/ Ast05-2-10/2005 (H5N1). This is the first report of HPAI subtype H5N1 in Bosnia and Herzegovina.

  11. Virus-like particles displaying H5, H7, H9 hemagglutinins and N1 neuraminidase elicit protective immunity to heterologous avian influenza viruses in chickens

    International Nuclear Information System (INIS)

    Pushko, Peter; Tretyakova, Irina; Hidajat, Rachmat; Zsak, Aniko; Chrzastek, Klaudia; Tumpey, Terrence M.; Kapczynski, Darrell R.

    2017-01-01

    Avian influenza (AI) viruses circulating in wild birds pose a serious threat to public health. Human and veterinary vaccines against AI subtypes are needed. Here we prepared triple-subtype VLPs that co-localized H5, H7 and H9 antigens derived from H5N1, H7N3 and H9N2 viruses. VLPs also contained influenza N1 neuraminidase and retroviral gag protein. The H5/H7/H9/N1/gag VLPs were prepared using baculovirus expression. Biochemical, functional and antigenic characteristics were determined including hemagglutination and neuraminidase enzyme activities. VLPs were further evaluated in a chicken AI challenge model for safety, immunogenicity and protective efficacy against heterologous AI viruses including H5N2, H7N3 and H9N2 subtypes. All vaccinated birds survived challenges with H5N2 and H7N3 highly pathogenic AI (HPAI) viruses, while all controls died. Immune response was also detectable after challenge with low pathogenicity AI (LPAI) H9N2 virus suggesting that H5/H7/H9/N1/gag VLPs represent a promising approach for the development of broadly protective AI vaccine. - Highlights: •VLPs were prepared that co-localized H5, H7 and H9 subtypes in a VLP envelope. •VLPs were characterized including electron microscopy, HA assay and NA enzyme activity. •Experimental VLP vaccine was evaluated in an avian influenza challenge model. •VLPs induced immune responses against heterologous H5, H7 and H9 virus challenges.

  12. Virus-like particles displaying H5, H7, H9 hemagglutinins and N1 neuraminidase elicit protective immunity to heterologous avian influenza viruses in chickens

    Energy Technology Data Exchange (ETDEWEB)

    Pushko, Peter, E-mail: ppushko@medigen-usa.com [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Tretyakova, Irina; Hidajat, Rachmat [Medigen, Inc., 8420 Gas House Pike, Suite S, Frederick, MD 21701 (United States); Zsak, Aniko; Chrzastek, Klaudia [USDA SEPRL, 934 College Station Rd, Athens, GA (United States); Tumpey, Terrence M. [Influenza Division, CDC,1600 Clifton Road N.E., Atlanta, GA (United States); Kapczynski, Darrell R. [USDA SEPRL, 934 College Station Rd, Athens, GA (United States)

    2017-01-15

    Avian influenza (AI) viruses circulating in wild birds pose a serious threat to public health. Human and veterinary vaccines against AI subtypes are needed. Here we prepared triple-subtype VLPs that co-localized H5, H7 and H9 antigens derived from H5N1, H7N3 and H9N2 viruses. VLPs also contained influenza N1 neuraminidase and retroviral gag protein. The H5/H7/H9/N1/gag VLPs were prepared using baculovirus expression. Biochemical, functional and antigenic characteristics were determined including hemagglutination and neuraminidase enzyme activities. VLPs were further evaluated in a chicken AI challenge model for safety, immunogenicity and protective efficacy against heterologous AI viruses including H5N2, H7N3 and H9N2 subtypes. All vaccinated birds survived challenges with H5N2 and H7N3 highly pathogenic AI (HPAI) viruses, while all controls died. Immune response was also detectable after challenge with low pathogenicity AI (LPAI) H9N2 virus suggesting that H5/H7/H9/N1/gag VLPs represent a promising approach for the development of broadly protective AI vaccine. - Highlights: •VLPs were prepared that co-localized H5, H7 and H9 subtypes in a VLP envelope. •VLPs were characterized including electron microscopy, HA assay and NA enzyme activity. •Experimental VLP vaccine was evaluated in an avian influenza challenge model. •VLPs induced immune responses against heterologous H5, H7 and H9 virus challenges.

  13. Non-Attenuation Of Highly Pathogenic Avian Influenza H5N1 By ...

    African Journals Online (AJOL)

    Avian influenza H5N1 represents one of the most researched viruses in laboratories world-wide in recent times with regards to its epidemiology, ecology, biology and geography. The virus has caused 409 human cases and 256 human fatalities to date. Some laboratory activities and other lab related works predispose ...

  14. Stabilization of Live Attenuated Influenza Vaccines by Freeze Drying, Spray Drying, and Foam Drying.

    Science.gov (United States)

    Lovalenti, Phillip M; Anderl, Jeff; Yee, Luisa; Nguyen, Van; Ghavami, Behnaz; Ohtake, Satoshi; Saxena, Atul; Voss, Thomas; Truong-Le, Vu

    2016-05-01

    The goal of this research is to develop stable formulations for live attenuated influenza vaccines (LAIV) by employing the drying methods freeze drying, spray drying, and foam drying. Formulated live attenuated Type-A H1N1 and B-strain influenza vaccines with a variety of excipient combinations were dried using one of the three drying methods. Process and storage stability at 4, 25 and 37°C of the LAIV in these formulations was monitored using a TCID50 potency assay. Their immunogenicity was also evaluated in a ferret model. The thermal stability of H1N1 vaccine was significantly enhanced through application of unique formulation combinations and drying processes. Foam dried formulations were as much as an order of magnitude more stable than either spray dried or freeze dried formulations, while exhibiting low process loss and full retention of immunogenicity. Based on long-term stability data, foam dried formulations exhibited a shelf life at 4, 25 and 37°C of >2, 1.5 years and 4.5 months, respectively. Foam dried LAIV Type-B manufactured using the same formulation and process parameters as H1N1 were imparted with a similar level of stability. Foam drying processing methods with appropriate selection of formulation components can produce an order of magnitude improvement in LAIV stability over other drying methods.

  15. Single-dose mucosal immunization with a candidate universal influenza vaccine provides rapid protection from virulent H5N1, H3N2 and H1N1 viruses.

    Directory of Open Access Journals (Sweden)

    Graeme E Price

    2010-10-01

    Full Text Available The sudden emergence of novel influenza viruses is a global public health concern. Conventional influenza vaccines targeting the highly variable surface glycoproteins hemagglutinin and neuraminidase must antigenically match the emerging strain to be effective. In contrast, "universal" vaccines targeting conserved viral components could be used regardless of viral strain or subtype. Previous approaches to universal vaccination have required protracted multi-dose immunizations. Here we evaluate a single dose universal vaccine strategy using recombinant adenoviruses (rAd expressing the conserved influenza virus antigens matrix 2 and nucleoprotein.In BALB/c mice, administration of rAd via the intranasal route was superior to intramuscular immunization for induction of mucosal responses and for protection against highly virulent H1N1, H3N2, or H5N1 influenza virus challenge. Mucosally vaccinated mice not only survived, but had little morbidity and reduced lung virus titers. Protection was observed as early as 2 weeks post-immunization, and lasted at least 10 months, as did antibodies and lung T cells with activated phenotypes. Virus-specific IgA correlated with but was not essential for protection, as demonstrated in studies with IgA-deficient animals.Mucosal administration of NP and M2-expressing rAd vectors provided rapid and lasting protection from influenza viruses in a subtype-independent manner. Such vaccines could be used in the interval between emergence of a new virus strain and availability of strain-matched vaccines against it. This strikingly effective single-dose vaccination thus represents a candidate off-the-shelf vaccine for emergency use during an influenza pandemic.

  16. Changes in the viral distribution pattern after the appearance of the novel influenza A H1N1 (pH1N1) virus in influenza-like illness patients in Peru.

    Science.gov (United States)

    Laguna-Torres, Victor Alberto; Gómez, Jorge; Aguilar, Patricia V; Ampuero, Julia S; Munayco, Cesar; Ocaña, Víctor; Pérez, Juan; Gamero, María E; Arrasco, Juan Carlos; Paz, Irmia; Chávez, Edward; Cruz, Rollin; Chavez, Jaime; Mendocilla, Silvia; Gomez, Elizabeth; Antigoni, Juana; Gonzalez, Sofía; Tejada, Cesar; Chowell, Gerardo; Kochel, Tadeusz J

    2010-07-27

    We describe the temporal variation in viral agents detected in influenza like illness (ILI) patients before and after the appearance of the ongoing pandemic influenza A (H1N1) (pH1N1) in Peru between 4-January and 13-July 2009. At the health centers, one oropharyngeal swab was obtained for viral isolation. From epidemiological week (EW) 1 to 18, at the US Naval Medical Research Center Detachment (NMRCD) in Lima, the specimens were inoculated into four cell lines for virus isolation. In addition, from EW 19 to 28, the specimens were also analyzed by real time-polymerase-chain-reaction (rRT-PCR). We enrolled 2,872 patients: 1,422 cases before the appearance of the pH1N1 virus, and 1,450 during the pandemic. Non-pH1N1 influenza A virus was the predominant viral strain circulating in Peru through (EW) 18, representing 57.8% of the confirmed cases; however, this predominance shifted to pH1N1 (51.5%) from EW 19-28. During this study period, most of pH1N1 cases were diagnosed in the capital city (Lima) followed by other cities including Cusco and Trujillo. In contrast, novel influenza cases were essentially absent in the tropical rain forest (jungle) cities during our study period. The city of Iquitos (Jungle) had the highest number of influenza B cases and only one pH1N1 case. The viral distribution in Peru changed upon the introduction of the pH1N1 virus compared to previous months. Although influenza A viruses continue to be the predominant viral pathogen, the pH1N1 virus predominated over the other influenza A viruses.

  17. Changes in the viral distribution pattern after the appearance of the novel influenza A H1N1 (pH1N1 virus in influenza-like illness patients in Peru.

    Directory of Open Access Journals (Sweden)

    Victor Alberto Laguna-Torres

    Full Text Available BACKGROUND: We describe the temporal variation in viral agents detected in influenza like illness (ILI patients before and after the appearance of the ongoing pandemic influenza A (H1N1 (pH1N1 in Peru between 4-January and 13-July 2009. METHODS: At the health centers, one oropharyngeal swab was obtained for viral isolation. From epidemiological week (EW 1 to 18, at the US Naval Medical Research Center Detachment (NMRCD in Lima, the specimens were inoculated into four cell lines for virus isolation. In addition, from EW 19 to 28, the specimens were also analyzed by real time-polymerase-chain-reaction (rRT-PCR. RESULTS: We enrolled 2,872 patients: 1,422 cases before the appearance of the pH1N1 virus, and 1,450 during the pandemic. Non-pH1N1 influenza A virus was the predominant viral strain circulating in Peru through (EW 18, representing 57.8% of the confirmed cases; however, this predominance shifted to pH1N1 (51.5% from EW 19-28. During this study period, most of pH1N1 cases were diagnosed in the capital city (Lima followed by other cities including Cusco and Trujillo. In contrast, novel influenza cases were essentially absent in the tropical rain forest (jungle cities during our study period. The city of Iquitos (Jungle had the highest number of influenza B cases and only one pH1N1 case. CONCLUSIONS: The viral distribution in Peru changed upon the introduction of the pH1N1 virus compared to previous months. Although influenza A viruses continue to be the predominant viral pathogen, the pH1N1 virus predominated over the other influenza A viruses.

  18. Newcastle disease virus-based H5 influenza vaccine protects chickens from lethal challenge with a highly pathogenic H5N2 avian influenza virus.

    Science.gov (United States)

    Ma, Jingjiao; Lee, Jinhwa; Liu, Haixia; Mena, Ignacio; Davis, A Sally; Sunwoo, Sun Young; Lang, Yuekun; Duff, Michael; Morozov, Igor; Li, Yuhao; Yang, Jianmei; García-Sastre, Adolfo; Richt, Juergen A; Ma, Wenjun

    2017-01-01

    Since December 2014, Eurasian-origin, highly pathogenic avian influenza H5 viruses including H5N1, H5N2, and H5N8 subtypes (called H5N x viruses), which belong to the H5 clade 2.3.4.4, have been detected in U.S. wild birds. Subsequently, highly pathogenic H5N2 and H5N8 viruses have caused outbreaks in U.S. domestic poultry. Vaccination is one of the most effective ways to control influenza outbreaks and protect animal and public health. Newcastle disease virus (NDV)-based influenza vaccines have been demonstrated to be efficacious and safe in poultry. Herein, we developed an NDV-based H5 vaccine (NDV-H5) that expresses a codon-optimized ectodomain of the hemagglutinin from the A/chicken/Iowa/04-20/2015 (H5N2) virus and evaluated its efficacy in chickens. Results showed that both live and inactivated NDV-H5 vaccines induced hemagglutinin inhibition antibody titers against the H5N2 virus in immunized chickens after prime and booster, and both NDV-H5 vaccines completely protected chickens from lethal challenge with the highly pathogenic H5N2 A/turkey/Minnesota/9845-4/2015 virus. No clinical signs and only minimal virus shedding was observed in both vaccinated groups. In contrast, all mock-vaccinated, H5N2-infected chickens shed virus and died within 5 days post challenge. Furthermore, one dose of the live NDV-H5 vaccine also provided protection of 90% chickens immunized by coarse spraying; after exposure to H5N2 challenge, sera from vaccinated surviving chickens neutralized both highly pathogenic H5N1 and H5N8 viruses. Taken together, our results suggest that the NDV-based H5 vaccine is able to protect chickens against intercontinental highly pathogenic H5N x viruses and can be used by mass application to protect the poultry industry.

  19. Epidemiological characteristics of Pandemic Influenza A (H1N1 ...

    African Journals Online (AJOL)

    Background: A novel influenza A virus strain (H1N1-2009) spread first in Mexico and the United Stated in late April 2009, leading to the first influenza pandemic of the 21st century. The objective of this study was to determine the epidemiological and virological characteristics of the pandemic influenza A (H1N1-2009) in ...

  20. Epidemiological characteristics of Pandemic Influenza A (H1N1 ...

    African Journals Online (AJOL)

    ... novel influenza A virus strain (H1N1-2009) spread first in Mexico and the United Stated in late April 2009, leading to the first influenza pandemic of the 21st century. The objective of this study was to determine the epidemiological and virological characteristics of the pandemic influenza A (H1N1-2009) in Zhanjiang, China ...

  1. Comprehensive global amino acid sequence analysis of PB1F2 protein of influenza A H5N1 viruses and the influenza A virus subtypes responsible for the 20th‐century pandemics

    Science.gov (United States)

    Pasricha, Gunisha; Mishra, Akhilesh C.; Chakrabarti, Alok K.

    2012-01-01

    Please cite this paper as: Pasricha et al. (2012) Comprehensive global amino acid sequence analysis of PB1F2 protein of influenza A H5N1 viruses and the Influenza A virus subtypes responsible for the 20th‐century pandemics. Influenza and Other Respiratory Viruses 7(4), 497–505. Background  PB1F2 is the 11th protein of influenza A virus translated from +1 alternate reading frame of PB1 gene. Since the discovery, varying sizes and functions of the PB1F2 protein of influenza A viruses have been reported. Selection of PB1 gene segment in the pandemics, variable size and pleiotropic effect of PB1F2 intrigued us to analyze amino acid sequences of this protein in various influenza A viruses. Methods  Amino acid sequences for PB1F2 protein of influenza A H5N1, H1N1, H2N2, and H3N2 subtypes were obtained from Influenza Research Database. Multiple sequence alignments of the PB1F2 protein sequences of the aforementioned subtypes were used to determine the size, variable and conserved domains and to perform mutational analysis. Results  Analysis showed that 96·4% of the H5N1 influenza viruses harbored full‐length PB1F2 protein. Except for the 2009 pandemic H1N1 virus, all the subtypes of the 20th‐century pandemic influenza viruses contained full‐length PB1F2 protein. Through the years, PB1F2 protein of the H1N1 and H3N2 viruses has undergone much variation. PB1F2 protein sequences of H5N1 viruses showed both human‐ and avian host‐specific conserved domains. Global database of PB1F2 protein revealed that N66S mutation was present only in 3·8% of the H5N1 strains. We found a novel mutation, N84S in the PB1F2 protein of 9·35% of the highly pathogenic avian influenza H5N1 influenza viruses. Conclusions  Varying sizes and mutations of the PB1F2 protein in different influenza A virus subtypes with pandemic potential were obtained. There was genetic divergence of the protein in various hosts which highlighted the host‐specific evolution of the virus

  2. Experimental infection with H1N1 European swine influenza virus protects pigs from an infection with the 2009 pandemic H1N1 human influenza virus.

    Science.gov (United States)

    Busquets, Núria; Segalés, Joaquim; Córdoba, Lorena; Mussá, Tufaria; Crisci, Elisa; Martín-Valls, Gerard E; Simon-Grifé, Meritxell; Pérez-Simó, Marta; Pérez-Maíllo, Monica; Núñez, Jose I; Abad, Francesc X; Fraile, Lorenzo; Pina, Sonia; Majó, Natalia; Bensaid, Albert; Domingo, Mariano; Montoya, María

    2010-01-01

    The recent pandemic caused by human influenza virus A(H1N1) 2009 contains ancestral gene segments from North American and Eurasian swine lineages as well as from avian and human influenza lineages. The emergence of this A(H1N1) 2009 poses a potential global threat for human health and the fact that it can infect other species, like pigs, favours a possible encounter with other influenza viruses circulating in swine herds. In Europe, H1N1, H1N2 and H3N2 subtypes of swine influenza virus currently have a high prevalence in commercial farms. To better assess the risk posed by the A(H1N1) 2009 in the actual situation of swine farms, we sought to analyze whether a previous infection with a circulating European avian-like swine A/Swine/Spain/53207/2004 (H1N1) influenza virus (hereafter referred to as SwH1N1) generated or not cross-protective immunity against a subsequent infection with the new human pandemic A/Catalonia/63/2009 (H1N1) influenza virus (hereafter referred to as pH1N1) 21 days apart. Pigs infected only with pH1N1 had mild to moderate pathological findings, consisting on broncho-interstitial pneumonia. However, pigs inoculated with SwH1N1 virus and subsequently infected with pH1N1 had very mild lung lesions, apparently attributed to the remaining lesions caused by SwH1N1 infection. These later pigs also exhibited boosted levels of specific antibodies. Finally, animals firstly infected with SwH1N1 virus and latter infected with pH1N1 exhibited undetectable viral RNA load in nasal swabs and lungs after challenge with pH1N1, indicating a cross-protective effect between both strains. © INRA, EDP Sciences, 2010.

  3. Pandemic influenza – including a risk assessment of H5N1

    Science.gov (United States)

    Taubenberger, J.K.; Morens, D.M.

    2009-01-01

    Summary Influenza pandemics and epidemics have apparently occurred since at least the Middle Ages. When pandemics appear, 50% or more of an affected population can be infected in a single year, and the number of deaths caused by influenza can dramatically exceed what is normally expected. Since 1500, there appear to have been 13 or more influenza pandemics. In the past 120 years there were undoubted pandemics in 1889, 1918, 1957, 1968, and 1977. Although most experts believe we will face another influenza pandemic, it is impossible to predict when it will appear, where it will originate, or how severe it will be. Nor is there agreement about the subtype of influenza virus most likely to cause the next pandemic. The continuing spread of H5N1 highly pathogenic avian influenza viruses has heightened interest in pandemic prediction. Despite uncertainties in the historical record of the pre-virology era, study of previous pandemics may help guide future pandemic planning and lead to a better understanding of the complex ecobiology underlying the formation of pandemic strains of influenza A viruses. PMID:19618626

  4. Cross-protection against lethal H5N1 challenge ferrets with an adjuvanted pandemic influenza vaccine

    NARCIS (Netherlands)

    B. Baras (Benoît); K.J. Stittelaar (Koert); J.H. Simon (James); R.J.M.M. Thoolen (Robert); S.P. Mossman (Sally); F.H. Pistoor (Frank); G. van Amerongen (Geert); M.A. Wettendorff (Martine); E. Hanon (Emmanuel); A.D.M.E. Osterhaus (Albert)

    2008-01-01

    textabstractBackground. Unprecedented spread between birds and mammals of highly pathogenic avian influenza viruses (HPAI) of the H5N1 subtype has resulted in hundreds of human infections with a high fatality rate. This has highlighted the urgent need for the development of H5N1 vaccines that can be

  5. Spatiotemporal structure of molecular evolution of H5N1 highly pathogenic avian influenza viruses in Vietnam.

    Science.gov (United States)

    Carrel, Margaret A; Emch, Michael; Jobe, R Todd; Moody, Aaron; Wan, Xiu-Feng

    2010-01-08

    Vietnam is one of the countries most affected by outbreaks of H5N1 highly pathogenic avian influenza viruses. First identified in Vietnam in poultry in 2001 and in humans in 2004, the virus has since caused 111 cases and 56 deaths in humans. In 2003/2004 H5N1 outbreaks, nearly the entire poultry population of Vietnam was culled. Our earlier study (Wan et al., 2008, PLoS ONE, 3(10): e3462) demonstrated that there have been at least six independent H5N1 introductions into Vietnam and there were nine newly emerged reassortants from 2001 to 2007 in Vietnam. H5N1 viruses in Vietnam cluster distinctly around Hanoi and Ho Chi Minh City. However, the nature of the relationship between genetic divergence and geographic patterns is still unclear. In this study, we hypothesized that genetic distances between H5N1 viruses in Vietnam are correlated with geographic distances, as the result of distinct population and environment patterns along Vietnam's long north to south longitudinal extent. Based on this hypothesis, we combined spatial statistical methods with genetic analytic techniques and explicitly used geographic space to explore genetic evolution of H5N1 highly pathogenic avian influenza viruses at the sub-national scale in Vietnam. Our dataset consisted of 125 influenza viruses (with whole genome sets) isolated in Vietnam from 2003 to 2007. Our results document the significant effect of space and time on genetic evolution and the rise of two regional centers of genetic mixing by 2007. These findings give insight into processes underlying viral evolution and suggest that genetic differentiation is associated with the distance between concentrations of human and poultry populations around Hanoi and Ho Chi Minh City. The results show that genetic evolution of H5N1 viruses in Vietnamese domestic poultry is highly correlated with the location and spread of those viruses in geographic space. This correlation varies by scale, time, and gene, though a classic isolation by

  6. Highly Pathogenic Avian Influenza A(H5N1) Virus Struck Migratory Birds in China in 2015.

    Science.gov (United States)

    Bi, Yuhai; Zhang, Zhenjie; Liu, Wenjun; Yin, Yanbo; Hong, Jianmin; Li, Xiangdong; Wang, Haiming; Wong, Gary; Chen, Jianjun; Li, Yunfeng; Ru, Wendong; Gao, Ruyi; Liu, Di; Liu, Yingxia; Zhou, Boping; Gao, George F; Shi, Weifeng; Lei, Fumin

    2015-08-11

    Approximately 100 migratory birds, including whooper swans and pochards, were found dead in the Sanmenxia Reservoir Area of China during January 2015. The causative agent behind this outbreak was identified as H5N1 highly pathogenic avian influenza virus (HPAIV). Genetic and phylogenetic analyses revealed that this Sanmenxia H5N1 virus was a novel reassortant, possessing a Clade 2.3.2.1c HA gene and a H9N2-derived PB2 gene. Sanmenxia Clade 2.3.2.1c-like H5N1 viruses possess the closest genetic identity to A/Alberta/01/2014 (H5N1), which recently caused a fatal respiratory infection in Canada with signs of meningoencephalitis, a highly unusual symptom with influenza infections in humans. Furthermore, this virus was shown to be highly pathogenic to both birds and mammals, and demonstrate tropism for the nervous system. Due to the geographical location of Sanmenxia, these novel H5N1 viruses also have the potential to be imported to other regions through the migration of wild birds, similar to the H5N1 outbreak amongst migratory birds in Qinghai Lake during 2005. Therefore, further investigation and monitoring is required to prevent this novel reassortant virus from becoming a new threat to public health.

  7. Comprehensive global amino acid sequence analysis of PB1F2 protein of influenza A H5N1 viruses and the influenza A virus subtypes responsible for the 20th-century pandemics.

    Science.gov (United States)

    Pasricha, Gunisha; Mishra, Akhilesh C; Chakrabarti, Alok K

    2013-07-01

    PB1F2 is the 11th protein of influenza A virus translated from +1 alternate reading frame of PB1 gene. Since the discovery, varying sizes and functions of the PB1F2 protein of influenza A viruses have been reported. Selection of PB1 gene segment in the pandemics, variable size and pleiotropic effect of PB1F2 intrigued us to analyze amino acid sequences of this protein in various influenza A viruses. Amino acid sequences for PB1F2 protein of influenza A H5N1, H1N1, H2N2, and H3N2 subtypes were obtained from Influenza Research Database. Multiple sequence alignments of the PB1F2 protein sequences of the aforementioned subtypes were used to determine the size, variable and conserved domains and to perform mutational analysis. Analysis showed that 96·4% of the H5N1 influenza viruses harbored full-length PB1F2 protein. Except for the 2009 pandemic H1N1 virus, all the subtypes of the 20th-century pandemic influenza viruses contained full-length PB1F2 protein. Through the years, PB1F2 protein of the H1N1 and H3N2 viruses has undergone much variation. PB1F2 protein sequences of H5N1 viruses showed both human- and avian host-specific conserved domains. Global database of PB1F2 protein revealed that N66S mutation was present only in 3·8% of the H5N1 strains. We found a novel mutation, N84S in the PB1F2 protein of 9·35% of the highly pathogenic avian influenza H5N1 influenza viruses. Varying sizes and mutations of the PB1F2 protein in different influenza A virus subtypes with pandemic potential were obtained. There was genetic divergence of the protein in various hosts which highlighted the host-specific evolution of the virus. However, studies are required to correlate this sequence variability with the virulence and pathogenicity. © 2012 John Wiley & Sons Ltd.

  8. Influenza A aviária (H5N1: a gripe do frango Avian influenza A (H5N1: the bird flu

    Directory of Open Access Journals (Sweden)

    Cássio da Cunha Ibiapina

    2005-10-01

    Full Text Available Este estudo tem como objetivo rever a literatura sobre o vírus influenza A aviária (H5N1. O levantamento bibliográfico foi realizado nos bancos de dados eletrônicos Medline, MD Consult, HighWire, Medscape e Literatura Latinoamericana y del Caribe en Ciencias de la Salud (LILACS, Literatura Latinoamericana e do Caribe em Ciências da Saúde, e por pesquisa direta, referentes aos últimos dez anos. Foram selecionados 32 artigos originais abordando os surtos recentes de infecção por um subtipo de vírus influenza A aviária, o H5N1, em criações de aves domésticas na Ásia, que resultaram em importantes prejuízos econômicos e repercussões em saúde pública, além de casos de infecção humana de alta letalidade. A maioria dos casos está associada com a exposição direta a aves infectadas ou superfícies contaminadas com excrementos dessas aves, porém foi confirmada a transmissão entre humanos. O período de incubação foi de dois a quatro dias. As manifestações clínicas variaram de infecção assintomática e doença leve do trato respiratório superior a pneumonia grave e falência múltipla de órgãos. A radiografia de tórax pode apresentar infiltrado intersticial bilateral, colapso lobar, consolidação focal e broncograma aéreo sem derrame pleural. A presença de linfopenia indica pior prognóstico. O tratamento de suporte parece ser o único tratamento aceitável. Os fatores de risco para mau prognóstico incluem idade avançada, demora na hospitalização, envolvimento do trato respiratório inferior, baixa contagem de leucócitos totais e linfopenia à admissão. Controlar os surtos em aves domésticas e o contato entre seres humanos e tais aves deve ser a prioridade no manejo da doença em nível de saúde pública, e medidas e conhecimentos acerca da doença devem ser amplamente divulgados.The objective of this study was to review the literature related to avian influenza A (H5N1. The bibliographic research was

  9. Purification and production of monospecific antibody to the hemagglutinin from Subtype H5N1 influenza virus

    Directory of Open Access Journals (Sweden)

    Simson Tarigan

    2010-12-01

    Full Text Available The purpose of this study was to purify the hemagglutinin from H5N1 virus and to generate monospecific antibody appropriate for production of sensitive and specific immunoassay for H5N1 avian influenza. For this purpose, a local isolate H5N1 virus (A/Ck/West Java/Hamd/2006 was propagated in chicken embryos. The viral pellet was dissolved in a Triton-X-100 solution, undissolved viral particles were pelleted by ultracentrifuge, and the supernatant containing viral surface glycoproteins (Hemagglutinin and neuraminidase was collected. The neuraminidase in the supernatant was absorbed by passing the supernatant through an Oxamic-acid-superose column. After dialyzing extensively, the filtrate was further fractionated with an anion exchange chromatography (Q-sepharose column. Proteins adsorbed by the column were eluted stepwisely with 0.10, 0.25, 0.25 and 0.75 M NaCl in 20 mM Tris, ph 8. Hemagglutinin (H5 was found to be eluted from the column with the 0.5 M NaCl elution buffer. The purified H5 was free from other viral proteins based on immunoassays using commercial antibodies to H5N1 nucleoprotein and neuraminidase. When used as ELISA’s coating antigen, the purified H5 proved to be sensitive and specific for hemagglutinin H5. Cross reactions with other type-A-influenza virus, H6, H7 dan H9, were negligibly low. For the production of monospecific antiserum, the purified H5 was separated with SDS-PAGE, the band containing the H5 monomer was cut out , homogenised and injected into rabbits. The antiserum was capable of detecting the presence of inactivated H5N1 virus in a very dilute suspension, with a detection limit of 0.04 heagglutination (HA unit. The purified hemagglutinin and the serum raised against it should be useful for developing specific, sensitive and affordable immunoassay for H5N1 avian influenza.

  10. Streptavidin-biotin-based directional double Nanobody sandwich ELISA for clinical rapid and sensitive detection of influenza H5N1.

    Science.gov (United States)

    Zhu, Min; Gong, Xue; Hu, Yonghong; Ou, Weijun; Wan, Yakun

    2014-12-20

    Influenza H5N1 is one subtype of the influenza A virus which can infect human bodies and lead to death. Timely diagnosis before its breakout is vital to the human health. The current clinical biochemical diagnosis for influenza virus are still flawed, and the diagnostic kits of H5N1 are mainly based on traditional monoclonal antibodies that hardly meet the requirements for clinical applications. Nanobody is a promising tool for diagnostics and treatment due to its smallest size, high specificity and stability. In this study, a novel Nanobody-based bioassay was developed for rapid, low-cost and sensitive detection of the influenza H5N1 virus. Nanobodies specific to H5N1 virus were selected from a VHH library by phage display technology. In this system, the biotinylated Nanobody was directionally captured by streptavidin coated on ELISA plate, which can specifically capture the H5N1 virus. Another Nanobody conjugated with HRP was used as a detector. A novel directional enzyme-linked immunosorbent assay for H5N1 using specific Nanobodies was established and compared to the conventional undirected ELISA assay. We have successfully constructed a high quality phage display Nanobody library and isolated two Nanobodies against H5N1 with high affinity and specificity. These two Nanobodies were further used to prepare the biosensor detection system. This streptavidin-biotin-based directional double Nanobodies sandwich ELISA for H5N1 detection showed superiority over the commonly undirectional ELISA protocol. The linear range of detection for standards in this immunoassay was approximately 50-1000 ng/mL and the detection limit was 14.1 ng/mL. The average recoveries of H5N1 virus from human serum samples were in the range from 94.58% to 114.51%, with a coefficient of variation less than 6.5%. Collectively, these results demonstrated that the proposed detection system is an alternative diagnostic tool that enables a rapid, inexpensive, sensitive and specific detection of the

  11. Seroprevalence of three influenza A viruses (H1N1, H3N2, and H3N8) in pet dogs presented to a veterinary hospital in Ohio.

    Science.gov (United States)

    Jang, Hyesun; Jackson, Yasmine K; Daniels, Joshua B; Ali, Ahmed; Kang, Kyung-Il; Elaish, Mohamed; Lee, Chang-Won

    2017-08-31

    The prevalence of canine H3N8 influenza and human H1N1 and H3N2 influenza in dogs in Ohio was estimated by conducting serologic tests on 1,082 canine serum samples. In addition, risk factors, such as health status and age were examined. The prevalences of human H1N1, H3N2, and canine H3N8 influenzas were 4.0%, 2.4%, and 2.3%, respectively. Two samples were seropositive for two subtypes (H1N1 and H3N2; H1N1 and canine influenza virus [CIV] H3N8). Compared to healthy dogs, dogs with respiratory signs were 5.795 times more likely to be seropositive against H1N1 virus ( p = 0.042). The prevalence of human flu infection increased with dog age and varied by serum collection month. The commercial enzyme-linked immunosorbent assay used in this study did not detect nucleoprotein-specific antibodies from many hemagglutination inhibition positive sera, which indicates a need for the development and validation of rapid tests for influenza screening in canine populations. In summary, we observed low exposure of dogs to CIV and human influenza viruses in Ohio but identified potential risk factors for consideration in future investigations. Our findings support the need for establishment of reliable diagnostic standards for serologic detection of influenza infection in canine species.

  12. Isolation and characterization of highly pathogenic avian influenza virus subtype H5N1 from donkeys

    Science.gov (United States)

    2010-01-01

    Background The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences. Methods Nasal swabs were collected from donkeys suffered from respiratory distress. The virus was isolated from the pooled nasal swabs in specific pathogen free embryonated chicken eggs (SPF-ECE). Reverse transcriptase polymerase chain reaction (RT-PCR) and sequencing of both haemagglutingin and neuraminidase were performed. H5 seroconversion was screened using haemagglutination inhibition (HI) assay on 105 donkey serum samples. Results We demonstrated that H5N1 jumped from poultry to another mammalian host; donkeys. Phylogenetic analysis showed that the virus clustered within the lineage of H5N1 from Egypt, closely related to 2009 isolates. It harboured few genetic changes compared to the closely related viruses from avian and humans. The neuraminidase lacks oseltamivir resistant mutations. Interestingly, HI screening for antibodies to H5 haemagglutinins in donkeys revealed high exposure rate. Conclusions These findings extend the host range of the H5N1 influenza virus, possess implications for influenza virus epidemiology and highlight the need for the systematic surveillance of H5N1 in animals in the vicinity of backyard poultry units especially in endemic areas. PMID:20398268

  13. Mortality, severe acute respiratory infection, and influenza-like illness associated with influenza A(H1N1pdm09 in Argentina, 2009.

    Directory of Open Access Journals (Sweden)

    Eduardo Azziz-Baumgartner

    Full Text Available INTRODUCTION: While there is much information about the burden of influenza A(H1N1pdm09 in North America, little data exist on its burden in South America. METHODS: During April to December 2009, we actively searched for persons with severe acute respiratory infection and influenza-like illness (ILI in three sentinel cities. A proportion of case-patients provided swabs for influenza testing. We estimated the number of case-patients that would have tested positive for influenza by multiplying the number of untested case-patients by the proportion who tested positive. We estimated rates by dividing the estimated number of case-patients by the census population after adjusting for the proportion of case-patients with missing illness onset information and ILI case-patients who visited physicians multiple times for one illness event. RESULTS: We estimated that the influenza A(H1N1pdm09 mortality rate per 100,000 person-years (py ranged from 1.5 among persons aged 5-44 years to 5.6 among persons aged ≥ 65 years. A(H1N1pdm09 hospitalization rates per 100,000 py ranged between 26.9 among children aged <5 years to 41.8 among persons aged ≥ 65 years. Influenza A(H1N1pdm09 ILI rates per 100 py ranged between 1.6 among children aged <5 to 17.1 among persons aged 45-64 years. While 9 (53% of 17 influenza A(H1N1pdm09 decedents with available data had obesity and 7 (17% of 40 had diabetes, less than 4% of surviving influenza A(H1N1pdm09 case-patients had these pre-existing conditions (p ≤ 0.001. CONCLUSION: Influenza A(H1N1pdm09 caused a similar burden of disease in Argentina as in other countries. Such disease burden suggests the potential value of timely influenza vaccinations.

  14. Fitness of Pandemic H1N1 and Seasonal influenza A viruses during Co-infection: Evidence of competitive advantage of pandemic H1N1 influenza versus seasonal influenza.

    Science.gov (United States)

    Perez, Daniel Roberto; Sorrell, Erin; Angel, Matthew; Ye, Jianqiang; Hickman, Danielle; Pena, Lindomar; Ramirez-Nieto, Gloria; Kimble, Brian; Araya, Yonas

    2009-08-24

    On June 11, 2009 the World Health Organization (WHO) declared a new H1N1 influenza pandemic. This pandemic strain is as transmissible as seasonal H1N1 and H3N2 influenza A viruses. Major concerns facing this pandemic are whether the new virus will replace, co-circulate and/or reassort with seasonal H1N1 and/or H3N2 human strains. Using the ferret model, we investigated which of these three possibilities were most likely favored. Our studies showed that the current pandemic virus is more transmissible than, and has a biological advantage over, prototypical seasonal H1 or H3 strains.

  15. Comparative analyses of pandemic H1N1 and seasonal H1N1, H3N2, and influenza B infections depict distinct clinical pictures in ferrets.

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    Stephen S H Huang

    Full Text Available Influenza A and B infections are a worldwide health concern to both humans and animals. High genetic evolution rates of the influenza virus allow the constant emergence of new strains and cause illness variation. Since human influenza infections are often complicated by secondary factors such as age and underlying medical conditions, strain or subtype specific clinical features are difficult to assess. Here we infected ferrets with 13 currently circulating influenza strains (including strains of pandemic 2009 H1N1 [H1N1pdm] and seasonal A/H1N1, A/H3N2, and B viruses. The clinical parameters were measured daily for 14 days in stable environmental conditions to compare clinical characteristics. We found that H1N1pdm strains had a more severe physiological impact than all season strains where pandemic A/California/07/2009 was the most clinically pathogenic pandemic strain. The most serious illness among seasonal A/H1N1 and A/H3N2 groups was caused by A/Solomon Islands/03/2006 and A/Perth/16/2009, respectively. Among the 13 studied strains, B/Hubei-Wujiagang/158/2009 presented the mildest clinical symptoms. We have also discovered that disease severity (by clinical illness and histopathology correlated with influenza specific antibody response but not viral replication in the upper respiratory tract. H1N1pdm induced the highest and most rapid antibody response followed by seasonal A/H3N2, seasonal A/H1N1 and seasonal influenza B (with B/Hubei-Wujiagang/158/2009 inducing the weakest response. Our study is the first to compare the clinical features of multiple circulating influenza strains in ferrets. These findings will help to characterize the clinical pictures of specific influenza strains as well as give insights into the development and administration of appropriate influenza therapeutics.

  16. Avian influenza virus (H5N1; effects of physico-chemical factors on its survival

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    Hameed Sajid

    2009-03-01

    Full Text Available Abstract Present study was performed to determine the effects of physical and chemical agents on infective potential of highly pathogenic avian influenza (HPAI H5N1 (local strain virus recently isolated in Pakistan during 2006 outbreak. H5N1 virus having titer 108.3 ELD50/ml was mixed with sterilized peptone water to get final dilution of 4HA units and then exposed to physical (temperature, pH and ultraviolet light and chemical (formalin, phenol crystals, iodine crystals, CID 20, virkon®-S, zeptin 10%, KEPCIDE 300, KEPCIDE 400, lifebuoy, surf excel and caustic soda agents. Harvested amnio-allantoic fluid (AAF from embryonated chicken eggs inoculated with H5N1 treated virus (0.2 ml/egg was subjected to haemagglutination (HA and haemagglutination inhibition (HI tests. H5N1 virus lost infectivity after 30 min at 56°C, after 1 day at 28°C but remained viable for more than 100 days at 4°C. Acidic pH (1, 3 and basic pH (11, 13 were virucidal after 6 h contact time; however virus retained infectivity at pH 5 (18 h, 7 and 9 (more than 24 h. UV light was proved ineffectual in inactivating virus completely even after 60 min. Soap (lifebuoy®, detergent (surf excel® and alkali (caustic soda destroyed infectivity after 5 min at 0.1, 0.2 and 0.3% dilution. All commercially available disinfectants inactivated virus at recommended concentrations. Results of present study would be helpful in implementing bio-security measures at farms/hatcheries levels in the wake of avian influenza virus (AIV outbreak.

  17. Passive immunotherapy for influenza A H5N1 virus infection with equine hyperimmune globulin F(ab'2 in mice

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    Li Yanbin

    2006-03-01

    Full Text Available Abstract Background Avian influenza virus H5N1 has demonstrated considerable pandemic potential. Currently, no effective vaccines for H5N1 infection are available, so passive immunotherapy may be an alternative strategy. To investigate the possible therapeutic effect of antibody against highly pathogenic H5N1 virus on a mammal host, we prepared specific equine anti-H5N1 IgGs from horses vaccinated with inactivated H5N1 virus, and then obtained the F(ab'2 fragments by pepsin digestion of IgGs. Methods The horses were vaccinated with inactivated H5N1 vaccine to prepare anti-H5N1 IgGs. The F(ab'2 fragments were purified from anti-H5N1 hyperimmune sera by a protocol for 'enhanced pepsin digestion'. The protective effect of the F(ab'2 fragments against H5N1 virus infection was determined in cultured MDCK cells by cytopathic effect (CPE assay and in a BALB/c mouse model by survival rate assay. Results By the protocol for 'enhanced pepsin digestion', total 16 g F(ab'2 fragments were finally obtained from one liter equine antisera with the purity of over 90%. The H5N1-specific F(ab'2 fragments had a HI titer of 1:1024, and the neutralization titre of F(ab'2 reached 1: 2048. The in vivo assay showed that 100 μg of the F(ab'2 fragments could protect BALB/c mice infected with a lethal dose of influenza H5N1 virus. Conclusion The availability of highly purified H5N1-specific F(ab'2 fragments may be promising for treatment of influenza H5N1 infection. Our work has provided experimental support for the application of the therapeutic equine immunoglobulin in future large primate or human trials.

  18. MVA-based H5N1 vaccine affords cross-clade protection in mice against influenza A/H5N1 viruses at low doses and after single immunization.

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    Joost H C M Kreijtz

    Full Text Available Human infections with highly pathogenic avian influenza viruses of the H5N1 subtype, frequently reported since 2003, result in high morbidity and mortality. It is feared that these viruses become pandemic, therefore the development of safe and effective vaccines is desirable. MVA-based H5N1 vaccines already proved to be effective when two immunizations with high doses were used. Dose-sparing strategies would increase the number of people that can be vaccinated when the amount of vaccine preparations that can be produced is limited. Furthermore, protective immunity is induced ideally after a single immunization. Therefore the minimal requirements for induction of protective immunity with a MVA-based H5N1 vaccine were assessed in mice. To this end, mice were vaccinated once or twice with descending doses of a recombinant MVA expressing the HA gene of influenza virus A/Vietnam/1194/04. The protective efficacy was determined after challenge infection with the homologous clade 1 virus and a heterologous virus derived from clade 2.1, A/Indonesia/5/05 by assessing weight loss, virus replication and histopathological changes. It was concluded that MVA-based vaccines allowed significant dose-sparing and afford cross-clade protection, also after a single immunization, which are favorable properties for an H5N1 vaccine candidate.

  19. La influenza A (H1N1: estado actual del conocimiento Influenza A (H1N1 virus: current information

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    Laura Margarita González Valdés

    2010-03-01

    Full Text Available Se revisó la bibliografía actualizada sobre el tema a partir de los principales buscadores, y reuniones internacionales realizadas sobre la pandemia de la influenza A (H1N1. Se tratan los aspectos relacionados con la historia, la aparición de la pandemia, la biología de la enfermedad, la epidemiología, el cuadro clínico, el tratamiento y el pronóstico y la prevención. La gripe A (H1N1 es una pandemia causada por una variante nueva del virus de la Influenza A que ha sufrido cambios antigénicos en la hemaglutinina y la neuraminidasa. Esto hace que la población sea altamente vulnerable a la infección y produce una sobrecarga temporal enorme a los servicios de salud. El virus se trasmite como otros virus Influenza. Su letalidad es similar a la de la influenza estacional, pero puede incrementarse en personas con factores de riesgo y en adultos jóvenes sanos. El asma y el embarazo parecen ser condiciones de base importantes para incrementar la severidad de la infección. Puede existir cierta protección por inmunidad cruzada con cepas que circularon en el pasado. El espectro clínico va desde personas asintomáticas hasta las formas graves que requieren internación en cuidados intensivos, con rápido deterioro hasta llegar a la insuficiencia respiratoria en un plazo de 24 horas. La vacunación durante la pandemia no parece ser suficientemente efectiva. Son necesarios antivirales (oseltamivir y zanamivir, y las medidas preventivas higiénico-sanitarias son muy eficaces.An updated review using the main search motors and international meetings already celebrated related to Influenza A H1N1 pandemics. Items related to the history, the appearance of the pandemics, the biology of the disease, its epidemiology, clinics, treatment, prognosis and prevention. Grippe A H1N1 is a pandemic caused by a new variant of the Influenza A virus that has suffered antigenic changes in haemaglutinin and neuraminidase. This turns populations more susceptible to

  20. Development of a dual-protective live attenuated vaccine against H5N1 and H9N2 avian influenza viruses by modifying the NS1 gene.

    Science.gov (United States)

    Choi, Eun-hye; Song, Min-Suk; Park, Su-Jin; Pascua, Philippe Noriel Q; Baek, Yun Hee; Kwon, Hyeok-il; Kim, Eun-Ha; Kim, Semi; Jang, Hyung-Kwan; Poo, Haryoung; Kim, Chul-Joong; Choi, Young Ki

    2015-07-01

    An increasing number of outbreaks of avian influenza H5N1 and H9N2 viruses in poultry have caused serious economic losses and raised concerns for human health due to the risk of zoonotic transmission. However, licensed H5N1 and H9N2 vaccines for animals and humans have not been developed. Thus, to develop a dual H5N1 and H9N2 live-attenuated influenza vaccine (LAIV), the HA and NA genes from a virulent mouse-adapted avian H5N2 (A/WB/Korea/ma81/06) virus and a recently isolated chicken H9N2 (A/CK/Korea/116/06) virus, respectively, were introduced into the A/Puerto Rico/8/34 backbone expressing truncated NS1 proteins (NS1-73, NS1-86, NS1-101, NS1-122) but still possessing a full-length NS gene. Two H5N2/NS1-LAIV viruses (H5N2/NS1-86 and H5N2/NS1-101) were highly attenuated compared with the full-length and remaining H5N2/NS-LAIV viruses in a mouse model. Furthermore, viruses containing NS1 modifications were found to induce more IFN-β activation than viruses with full-length NS1 proteins and were correspondingly attenuated in mice. Intranasal vaccination with a single dose (10(4.0) PFU/ml) of these viruses completely protected mice from a lethal challenge with the homologous A/WB/Korea/ma81/06 (H5N2), heterologous highly pathogenic A/EM/Korea/W149/06 (H5N1), and heterosubtypic highly virulent mouse-adapted H9N2 viruses. This study clearly demonstrates that the modified H5N2/NS1-LAIV viruses attenuated through the introduction of mutations in the NS1 coding region display characteristics that are desirable for live attenuated vaccines and hold potential as vaccine candidates for mammalian hosts.

  1. Clinical outcomes of seasonal influenza and pandemic influenza A (H1N1 in pediatric inpatients

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    Budd Alicia

    2010-10-01

    Full Text Available Abstract Background In April 2009, a novel influenza A H1N1 (nH1N1 virus emerged and spread rapidly worldwide. News of the pandemic led to a heightened awareness of the consequences of influenza and generally resulted in enhanced infection control practices and strengthened vaccination efforts for both healthcare workers and the general population. Seasonal influenza (SI illness in the pediatric population has been previously shown to result in significant morbidity, mortality, and substantial hospital resource utilization. Although influenza pandemics have the possibility of resulting in considerable illness, we must not ignore the impact that we can experience annually with SI. Methods We compared the outcomes of pediatric patients ≤18 years of age at a large urban hospital with laboratory confirmed influenza and an influenza-like illness (ILI during the 2009 pandemic and two prior influenza seasons. The primary outcome measure was hospital length of stay (LOS. All variables potentially associated with LOS based on univariable analysis, previous studies, or hypothesized relationships were included in the regression models to ensure adjustment for their effects. Results There were 133 pediatric cases of nH1N1 admitted during 2009 and 133 cases of SI admitted during the prior 2 influenza seasons (2007-8 and 2008-9. Thirty-six percent of children with SI and 18% of children with nH1N1 had no preexisting medical conditions (p = 0.14. Children admitted with SI had 1.73 times longer adjusted LOS than children admitted for nH1N1 (95% CI 1.35 - 2.13. There was a trend towards more children with SI requiring mechanical ventilation compared with nH1N1 (16 vs.7, p = 0.08. Conclusions This study strengthens the growing body of evidence demonstrating that SI results in significant morbidity in the pediatric population. Pandemic H1N1 received considerable attention with strong media messages urging people to undergo vaccination and encouraging improved

  2. Impact of influenza in the post-pandemic phase: Clinical features in hospitalized patients with influenza A (H1N1) pdm09 and H3N2 viruses, during 2013 in Santa Fe, Argentina.

    Science.gov (United States)

    Kusznierz, Gabriela; Carolina, Cudós; Manuel, Rudi Juan; Sergio, Lejona; Lucila, Ortellao; Julio, Befani; Mirta, Villani; Pedro, Morana; Graciana, Morera; Andrea, Uboldi; Elsa, Zerbini

    2017-07-01

    It is important to characterize the clinical and epidemiological pattern of the influenza A (H1N1) pdm09 virus and compare it with influenza A (H3N2) virus, as surveyed in just a few studies, in order to contribute to the implementation and strengthening of influenza control and prevention strategies. The aims in this study were to describe influenza clinical and epidemiological characteristics in hospitalized patients, caused by influenza A (H1N1)pdm09 and influenza A (H3N2) viruses during 2013, in Santa Fe, Argentina. A retrospective study was conducted over 2013 among hospitalized patients with laboratory-confirmed influenza diagnosis. In contrast to patients with influenza A (H3N2) (20.5%), a higher proportion of hospitalizations associated with influenza H1N1pdm were reported among adults aged 35-65 years (42.8%). Of all patients, 73.6% had an underlying medical condition. Hospitalized patients with H1N1pdm were subject to 2.6 (95%CI, 1.0-6.8) times higher risk of severity, than those hospitalized with influenza A (H3N2). This results demonstrate the impact in the post-pandemic era of H1N1pdm virus, with increased risk of severe disease, in relation to H3N2 virus, both viruses co-circulating during 2013. © 2017 Wiley Periodicals, Inc.

  3. Oligomeric recombinant H5 HA1 vaccine produced in bacteria protects ferrets from homologous and heterologous wild-type H5N1 influenza challenge and controls viral loads better than subunit H5N1 vaccine by eliciting high-affinity antibodies.

    Science.gov (United States)

    Verma, Swati; Dimitrova, Milena; Munjal, Ashok; Fontana, Juan; Crevar, Corey J; Carter, Donald M; Ross, Ted M; Khurana, Surender; Golding, Hana

    2012-11-01

    Recombinant hemagglutinin from influenza viruses with pandemic potential can be produced rapidly in various cell substrates. In this study, we compared the functionality and immunogenicity of bacterially produced oligomeric or monomeric HA1 proteins from H5N1 (A/Vietnam/1203/04) with those of the egg-based licensed subunit H5N1 (SU-H5N1) vaccine in ferrets challenged with homologous or heterologous H5N1 highly pathogenic influenza strains. Ferrets were vaccinated twice with the oligomeric or monomeric rHA1 or with SU-H5N1 (Sanofi Pasteur) emulsified with Titermax adjuvant and were challenged with wild-type homologous (A/Vietnam/1203/04; clade 1) or heterologous (A/Whooperswan/Mongolia/244/2005; clade 2.2) virus. Only the oligomeric rHA1 (not the monomeric rHA1) immunogen and the SU-H5N1 vaccine provided protection against the lethality and morbidity of homologous and heterologous highly pathogenic H5N1. Oligomeric rHA1 generated more cross-neutralizing antibodies and higher levels of serum antibody binding to HA1, with stronger avidity and a better IgG/IgM ratio, than monomeric HA1 and SU-H5N1 vaccines, as determined by surface plasmon resonance (SPR). Importantly, viral loads after heterologous H5N1 challenge were more efficiently controlled in ferrets vaccinated with the oligomeric rHA1 immunogen than in SU-H5N1-vaccinated ferrets. The reduction of viral loads in the nasal washes correlated strongly with higher-avidity antibodies to oligomeric rHA1 derived from H5N1 clade 1 and clade 2.2 viruses, as measured by SPR. This is the first study to show the role of antibody avidity for the HA1 globular head domain in reduction of viral loads in the upper respiratory tract, which could significantly reduce viral transmission.

  4. Spatiotemporal structure of molecular evolution of H5N1 highly pathogenic avian influenza viruses in Vietnam.

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    Margaret A Carrel

    2010-01-01

    Full Text Available Vietnam is one of the countries most affected by outbreaks of H5N1 highly pathogenic avian influenza viruses. First identified in Vietnam in poultry in 2001 and in humans in 2004, the virus has since caused 111 cases and 56 deaths in humans. In 2003/2004 H5N1 outbreaks, nearly the entire poultry population of Vietnam was culled. Our earlier study (Wan et al., 2008, PLoS ONE, 3(10: e3462 demonstrated that there have been at least six independent H5N1 introductions into Vietnam and there were nine newly emerged reassortants from 2001 to 2007 in Vietnam. H5N1 viruses in Vietnam cluster distinctly around Hanoi and Ho Chi Minh City. However, the nature of the relationship between genetic divergence and geographic patterns is still unclear.In this study, we hypothesized that genetic distances between H5N1 viruses in Vietnam are correlated with geographic distances, as the result of distinct population and environment patterns along Vietnam's long north to south longitudinal extent. Based on this hypothesis, we combined spatial statistical methods with genetic analytic techniques and explicitly used geographic space to explore genetic evolution of H5N1 highly pathogenic avian influenza viruses at the sub-national scale in Vietnam. Our dataset consisted of 125 influenza viruses (with whole genome sets isolated in Vietnam from 2003 to 2007. Our results document the significant effect of space and time on genetic evolution and the rise of two regional centers of genetic mixing by 2007. These findings give insight into processes underlying viral evolution and suggest that genetic differentiation is associated with the distance between concentrations of human and poultry populations around Hanoi and Ho Chi Minh City.The results show that genetic evolution of H5N1 viruses in Vietnamese domestic poultry is highly correlated with the location and spread of those viruses in geographic space. This correlation varies by scale, time, and gene, though a classic

  5. Highly pathogenic avian influenza virus (H5N1) in experimentally infected adult mute swans.

    Science.gov (United States)

    Kalthoff, Donata; Breithaupt, Angele; Teifke, Jens P; Globig, Anja; Harder, Timm; Mettenleiter, Thomas C; Beer, Martin

    2008-08-01

    Adult, healthy mute swans were experimentally infected with highly pathogenic avian influenza virus A/Cygnus cygnus/Germany/R65/2006 subtype H5N1. Immunologically naive birds died, whereas animals with preexisting, naturally acquired avian influenza virus-specific antibodies became infected asymptomatically and shed virus. Adult mute swans are highly susceptible, excrete virus, and can be clinically protected by preexposure immunity.

  6. Isolation and characterization of highly pathogenic avian influenza virus subtype H5N1 from donkeys

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    Abdel-Ghany Ahmad E

    2010-04-01

    Full Text Available Abstract Background The highly pathogenic H5N1 is a major avian pathogen that crosses species barriers and seriously affects humans as well as some mammals. It mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences. Methods Nasal swabs were collected from donkeys suffered from respiratory distress. The virus was isolated from the pooled nasal swabs in specific pathogen free embryonated chicken eggs (SPF-ECE. Reverse transcriptase polymerase chain reaction (RT-PCR and sequencing of both haemagglutingin and neuraminidase were performed. H5 seroconversion was screened using haemagglutination inhibition (HI assay on 105 donkey serum samples. Results We demonstrated that H5N1 jumped from poultry to another mammalian host; donkeys. Phylogenetic analysis showed that the virus clustered within the lineage of H5N1 from Egypt, closely related to 2009 isolates. It harboured few genetic changes compared to the closely related viruses from avian and humans. The neuraminidase lacks oseltamivir resistant mutations. Interestingly, HI screening for antibodies to H5 haemagglutinins in donkeys revealed high exposure rate. Conclusions These findings extend the host range of the H5N1 influenza virus, possess implications for influenza virus epidemiology and highlight the need for the systematic surveillance of H5N1 in animals in the vicinity of backyard poultry units especially in endemic areas.

  7. Histopathological evaluation of the diversity of cells susceptible to H5N1 virulent avian influenza virus.

    Science.gov (United States)

    Ogiwara, Haru; Yasui, Fumihiko; Munekata, Keisuke; Takagi-Kamiya, Asako; Munakata, Tsubasa; Nomura, Namiko; Shibasaki, Futoshi; Kuwahara, Kazuhiko; Sakaguchi, Nobuo; Sakoda, Yoshihiro; Kida, Hiroshi; Kohara, Michinori

    2014-01-01

    Patients infected with highly pathogenic avian influenza A H5N1 viruses (H5N1 HPAIV) show diffuse alveolar damage. However, the temporal progression of tissue damage and repair after viral infection remains poorly defined. Therefore, we assessed the sequential histopathological characteristics of mouse lung after intranasal infection with H5N1 HPAIV or H1N1 2009 pandemic influenza virus (H1N1 pdm). We determined the amount and localization of virus in the lung through IHC staining and in situ hybridization. IHC used antibodies raised against the virus protein and antibodies specific for macrophages, type II pneumocytes, or proliferating cell nuclear antigen. In situ hybridization used RNA probes against both viral RNA and mRNA encoding the nucleoprotein and the hemagglutinin protein. H5N1 HPAIV infection and replication were observed in multiple lung cell types and might result in rapid progression of lung injury. Both type II pneumocytes and macrophages proliferated after H5N1 HPAIV infection. However, the abundant macrophages failed to block the viral attack, and proliferation of type II pneumocytes failed to restore the damaged alveoli. In contrast, mice infected with H1N1 pdm exhibited modest proliferation of type II pneumocytes and macrophages and slight alveolar damage. These results suggest that the virulence of H5N1 HPAIV results from the wide range of cell tropism of the virus, excessive virus replication, and rapid development of diffuse alveolar damage. Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.

  8. Contact variables for exposure to avian influenza H5N1 virus at the human-animal interface.

    Science.gov (United States)

    Rabinowitz, P; Perdue, M; Mumford, E

    2010-06-01

    Although the highly pathogenic avian influenza H5N1 virus continues to cause infections in both avian and human populations, the specific zoonotic risk factors remain poorly understood. This review summarizes available evidence regarding types of contact associated with transmission of H5N1 virus at the human-animal interface. A systematic search of the published literature revealed five analytical studies and 15 case reports describing avian influenza transmission from animals to humans for further review. Risk factors identified in analytical studies were compared, and World Health Organization-confirmed cases, identified in case reports, were classified according to type of contact reported using a standardized algorithm. Although cases were primarily associated with direct contact with sick/unexpectedly dead birds, some cases reported only indirect contact with birds or contaminated environments or contact with apparently healthy birds. Specific types of contacts or activities leading to exposure could not be determined from data available in the publications reviewed. These results support previous reports that direct contact with sick birds is not the only means of human exposure to avian influenza H5N1 virus. To target public health measures and disease awareness messaging for reducing the risk of zoonotic infection with avian influenza H5N1 virus, the specific types of contacts and activities leading to transmission need to be further understood. The role of environmental virus persistence, shedding of virus by asymptomatic poultry and disease pathophysiology in different avian species relative to human zoonotic risk, as well as specific modes of zoonotic transmission, should be determined.

  9. Multivalent HA DNA vaccination protects against highly pathogenic H5N1 avian influenza infection in chickens and mice.

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    Srinivas Rao

    Full Text Available Sustained outbreaks of highly pathogenic avian influenza (HPAI H5N1 in avian species increase the risk of reassortment and adaptation to humans. The ability to contain its spread in chickens would reduce this threat and help maintain the capacity for egg-based vaccine production. While vaccines offer the potential to control avian disease, a major concern of current vaccines is their potency and inability to protect against evolving avian influenza viruses.The ability of DNA vaccines encoding hemagglutinin (HA proteins from different HPAI H5N1 serotypes was evaluated for its ability to elicit neutralizing antibodies and to protect against homologous and heterologous HPAI H5N1 strain challenge in mice and chickens after DNA immunization by needle and syringe or with a pressure injection device. These vaccines elicited antibodies that neutralized multiple strains of HPAI H5N1 when given in combinations containing up to 10 HAs. The response was dose-dependent, and breadth was determined by the choice of the influenza virus HA in the vaccine. Monovalent and trivalent HA vaccines were tested first in mice and conferred protection against lethal H5N1 A/Vietnam/1203/2004 challenge 68 weeks after vaccination. In chickens, protection was observed against heterologous strains of HPAI H5N1 after vaccination with a trivalent H5 serotype DNA vaccine with doses as low as 5 microg DNA given twice either by intramuscular needle injection or with a needle-free device.DNA vaccines offer a generic approach to influenza virus immunization applicable to multiple animal species. In addition, the ability to substitute plasmids encoding different strains enables rapid adaptation of the vaccine to newly evolving field isolates.

  10. Hemagglutinin pseudotyped lentiviral particles: characterization of a new method for avian H5N1 influenza sero-diagnosis.

    OpenAIRE

    Nefkens , Isabelle; Garcia , Jean-Michel; Ling , Chu Shui; Lagarde , Nadège; Nicholls , John; Tang , Dong Jiang; Peiris , Malik; Buchy , Philippe; Altmeyer , Ralf

    2007-01-01

    BACKGROUND: Highly pathogenic avian influenza (HPAI) H5N1 has spread globally in birds and infected over 270 humans with an apparently high mortality rate. Serologic studies to determine the extent of asymptomatic H5N1 infection in humans and other mammals and to investigate the immunogenicity of current H5N1 vaccine candidates have been hampered by the biosafety requirements needed for H5N1 micro-neutralization tests. OBJECTIVE: Development of a serodiagnostic tool for highly pathogenic infl...

  11. (H1N1) Influenza in Saurashtra, India

    African Journals Online (AJOL)

    Mexico in April, 2009,[1] and then in United States (US).[2,3]. This was originally ... duration of hospital stay of such patients was 2‑32 days. All admitted A (H1N1) .... Because of limited resources, only 2009 A (H1N1) influenza virus was tested ...

  12. Evolution of highly pathogenic avian H5N1 influenza viruses

    Energy Technology Data Exchange (ETDEWEB)

    Macken, Catherine A [Los Alamos National Laboratory; Green, Margaret A [Los Alamos National Laboratory

    2009-01-01

    Highly pathogenic avian H5N1 viruses have circulated in Southeast Asia for more than a decade, are now endemic in parts of this region, and have also spread to more than 60 countries on three continents. The evolution of these viruses is characterized by frequent reassortment events that have created a significant number of different genotypes, both transient and longer lasting. However, fundamental questions remain about the generation and perpetuation of this substantial genetic diversity. These gaps in understanding may, in part, be due to the difficulties of genotyping closely related viruses, and limitations in the size of the data sets used in analysis. Using our recently published novel genotyping procedure ('two-time test'), which is amenable to high throughput analysis and provides an increased level of resolution relative to previous analyses, we propose a detailed model for the evolution and diversification of avian H5N1 viruses. Our analysis suggests that (i) all current H5N1 genotypes are derived from a single, clearly defined sequence of initial reassortment events; (ii) reassortment of the polymerase and NP genes may have played an important role in avian H5N1 virus evolution; (iii) the current genotype Z viruses have diverged into three distinguishable sub-genotypes in the absence of reassortment; (iv) some potentially significant molecular changes appear to be correlated with particular genotypes (for example, reassortment of the internal genes is often paralleled by a change in the HA clade); and (v) as noted in earlier studies of avian influenza A virus evolution, novel segments are typically derived from different donors (i.e., there is no obvious pattern of gene linkage in reassortment). The model of avian H5N1 viral evolution by reassortment and mutation that emerges from our study provides a context within which significant amino acid changes may be revealed; it also may help in predicting the 'success' of newly emerging

  13. Incidence and Epidemiology of Hospitalized Influenza Cases in Rural Thailand during the Influenza A (H1N1)pdm09 Pandemic, 2009–2010

    Science.gov (United States)

    Baggett, Henry C.; Chittaganpitch, Malinee; Thamthitiwat, Somsak; Prapasiri, Prabda; Naorat, Sathapana; Sawatwong, Pongpun; Ditsungnoen, Darunee; Olsen, Sonja J.; Simmerman, James M.; Srisaengchai, Prasong; Chantra, Somrak; Peruski, Leonard F.; Sawanpanyalert, Pathom; Maloney, Susan A.; Akarasewi, Pasakorn

    2012-01-01

    Background Data on the burden of the 2009 influenza pandemic in Asia are limited. Influenza A(H1N1)pdm09 was first reported in Thailand in May 2009. We assessed incidence and epidemiology of influenza-associated hospitalizations during 2009–2010. Methods We conducted active, population-based surveillance for hospitalized cases of acute lower respiratory infection (ALRI) in all 20 hospitals in two rural provinces. ALRI patients were sampled 1∶2 for participation in an etiology study in which nasopharyngeal swabs were collected for influenza virus testing by PCR. Results Of 7,207 patients tested, 902 (12.5%) were influenza-positive, including 190 (7.8%) of 2,436 children aged incidence of hospitalized influenza cases was 136 per 100,000, highest in ages 75 years (407 per 100,000). The incidence of influenza A(H1N1)pdm09 was 62 per 100,000 (214 per 100,000 in children <5 years). Eleven influenza-infected patients required mechanical ventilation, and four patients died, all adults with influenza A(H1N1)pdm09 (1) or H3N2 (3). Conclusions Influenza-associated hospitalization rates in Thailand during 2009–10 were substantial and exceeded rates described in western countries. Influenza A(H1N1)pdm09 predominated, but H3N2 also caused notable morbidity. Expanded influenza vaccination coverage could have considerable public health impact, especially in young children. PMID:23139802

  14. Novel reassortant of swine influenza H1N2 virus in Germany.

    Science.gov (United States)

    Zell, Roland; Motzke, Susann; Krumbholz, Andi; Wutzler, Peter; Herwig, Volker; Dürrwald, Ralf

    2008-01-01

    European porcine H1N2 influenza viruses arose after multiple reassortment steps involving a porcine influenza virus with avian-influenza-like internal segments and human H1N1 and H3N2 viruses in 1994. In Germany, H1N2 swine influenza viruses first appeared in 2000. Two German H1N2 swine influenza virus strains isolated from pigs with clinical symptoms of influenza are described. They were characterized by the neutralization test, haemagglutination inhibition (HI) test and complete sequencing of the viral genomes. The data demonstrate that these viruses represent a novel H1N2 reassortant. The viruses showed limited neutralization by sera raised against heterologous A/sw/Bakum/1,832/00-like H1N2 viruses. Sera pools from recovered pigs showed a considerably lower HI reaction, indicative of diagnostic difficulties in using the HI test to detect these viruses with A/sw/Bakum/1,832/00-like H1N2 antigens. Genome sequencing revealed the novel combination of the human-like HAH1 gene of European porcine H1N2 influenza viruses and the NAN2 gene of European porcine H3N2 viruses.

  15. Predictors of H1N1 influenza in the emergency department: proposition for a modified H1N1 case definition.

    Science.gov (United States)

    Flick, H; Drescher, M; Prattes, J; Tovilo, K; Kessler, H H; Vander, K; Seeber, K; Palfner, M; Raggam, R B; Avian, A; Krause, R; Hoenigl, M

    2014-02-01

    Reliable and rapid diagnosis of influenza A H1N1 is essential to initiate appropriate antiviral therapy and preventive measures. We analysed the differences in clinical presentation and laboratory parameters between emergency department patients with PCR-confirmed H1N1 influenza infection (n = 199) and those with PCR-negative influenza-like illness (ILI; n = 252). Cough, wheezing, leucopenia, eosinopenia and a lower C-reactive protein remained significant predictors of H1N1 influenza. Proposed combinations of clinical symptoms with simple laboratory parameters (e.g. reported or measured fever and either cough or leucocytes definitions that use clinical criteria alone. © 2013 The Authors Clinical Microbiology and Infection © 2013 European Society of Clinical Microbiology and Infectious Diseases.

  16. Protection from the 2009 H1N1 pandemic influenza by an antibody from combinatorial survivor-based libraries.

    Directory of Open Access Journals (Sweden)

    Arun K Kashyap

    2010-07-01

    Full Text Available Influenza viruses elude immune responses and antiviral chemotherapeutics through genetic drift and reassortment. As a result, the development of new strategies that attack a highly conserved viral function to prevent and/or treat influenza infection is being pursued. Such novel broadly acting antiviral therapies would be less susceptible to virus escape and provide a long lasting solution to the evolving virus challenge. Here we report the in vitro and in vivo activity of a human monoclonal antibody (A06 against two isolates of the 2009 H1N1 pandemic influenza virus. This antibody, which was obtained from a combinatorial library derived from a survivor of highly pathogenic H5N1 infection, neutralizes H5N1, seasonal H1N1 and 2009 "Swine" H1N1 pandemic influenza in vitro with similar potency and is capable of preventing and treating 2009 H1N1 influenza infection in murine models of disease. These results demonstrate broad activity of the A06 antibody and its utility as an anti-influenza treatment option, even against newly evolved influenza strains to which there is limited immunity in the general population.

  17. Multiplex Reverse Transcription-Polymerase Chain Reaction untuk Deteksi Cepat Virus Flu Burung H5N1 (MULTIPLEX REVERSE TRANSCRIPTION-POLYMERASE CHAIN REACTION FOR RAPID DETECTION OF H5N1 AVIAN INFLUENZA VIRUS

    Directory of Open Access Journals (Sweden)

    Raden Wasito

    2015-05-01

    Full Text Available Avian influenza virus subtype H5N1 (AIV H5N1 is highly pathogenic and fatal in poultry. The virusis still endemic with low virulence rate, although it may play a critical role in causing high morbidity andmortality rates in poultry in Indonesia. In general, diagnostic approach for AIV H5N1 is based onconventional serological and viral isolation methods that have the potential to produce consumings oftime and relatively expensive cost within the laboratory without compromising test utility. Thus, amolecular approach of multiplex reverse transcription-polymerase chain reaction (mRT-PCR was developedand applied for the detection of matrix gene type A influenza viruses, AIV subtype subtype H5hemagglutinin gene with simultaneous detection of N1 nucleoprotein gene. Thirty sera specimens fromthe diseased commercial chickens that were specifically amplified positive-RT-PCR for AIV H5N1 wereselected for mRT-PCR. The mRT-PCR products were visualized by agarose gel electrophoresis and consistedof DNA fragments of AIV of 245 bp, 545 bp and 343 bp for M, H5 and N1 genes, respectively. Thus, themRT-PCR that can rapidly differentiate simultaneously between these genes is very important for thecontrol and even eradication of AIV transmission in poultry in Indonesia.

  18. Anti-pandemic influenza A (H1N1) virus potential of catechin and gallic acid.

    Science.gov (United States)

    You, Huey-Ling; Huang, Chao-Chun; Chen, Chung-Jen; Chang, Cheng-Chin; Liao, Pei-Lin; Huang, Sheng-Teng

    2018-05-01

    The pandemic influenza A (H1N1) virus has spread worldwide and infected a large proportion of the human population. Discovery of new and effective drugs for the treatment of influenza is a crucial issue for the global medical community. According to our previous study, TSL-1, a fraction of the aqueous extract from the tender leaf of Toonasinensis, has demonstrated antiviral activities against pandemic influenza A (H1N1) through the down-regulation of adhesion molecules and chemokine to prevent viral attachment. The aim of the present study was to identify the active compounds in TSL-1 which exert anti-influenza A (H1N1) virus effects. XTT assay was used to detect the cell viability. Meanwhile, the inhibitory effect on the pandemic influenza A (H1N1) virus was analyzed by observing plaque formation, qRT-PCR, neuraminidase activity, and immunofluorescence staining of influenza A-specific glycoprotein. Both catechin and gallic acid were found to be potent inhibitors in terms of influenza virus mRNA replication and MDCK plaque formation. Additionally, both compounds inhibited neuraminidase activities and viral glycoprotein. The 50% effective inhibition concentration (EC 50 ) of catechin and gallic acid for the influenza A (H1N1) virus were 18.4 μg/mL and 2.6 μg/mL, respectively; whereas the 50% cytotoxic concentrations (CC 50 ) of catechin and gallic acid were >100 μg/mL and 22.1 μg/mL, respectively. Thus, the selectivity indexes (SI) of catechin and gallic acid were >5.6 and 22.1, respectively. The present study demonstrates that catechin might be a safe reagent for long-term use to prevent influenza A (H1N1) virus infection; whereas gallic acid might be a sensitive reagent to inhibit influenza virus infection. We conclude that these two phyto-chemicals in TSL-1 are responsible for exerting anti-pandemic influenza A (H1N1) virus effects. Copyright © 2017. Published by Elsevier Taiwan LLC.

  19. TEST KIT FOR THE DETECTION AND GENOTYPING OF HIGHLY PATHOGENIC INFLUENZA VIRUS A H5N1 BY REAL-TIME POLYMERASE CHAIN REACTION

    Directory of Open Access Journals (Sweden)

    S. V. Stepaniuk

    2014-06-01

    Full Text Available Results of the annual monitoring of epizooties indicate that highly pathogenic HPAI/H5N1 avian influenza widely circulated in Eurasian region. Over a period of 2010–2013 years more than 165 cases of outbreaks in 14 countries were found out. Ukraine became one of the first countries in Europe where in Autonomous Republic of Crimea in October 2005 outbreak of avian epizootic with HPAI/H5N1 was documented and until February 2008 more than 236,000 poultry were killed. Since then the question of monitoring of infected both migrating birds and poultry in places of cross contact in Ukraine remains of high priority. The test system is developed for identification and genotyping A H5N1 on three genes (M, H5 and N1 HPAI/H5N1 in real-time mode for polymerase chain reaction. Test kit capacity to detect HPAI/h5n1avian influenza virus and differentiate it from the other viral infection agents of birds and animals were studied by testing of HPAI/H5N1 virus isolated during mass infection outbreak in Crimea in 2005 and cultural specimens of other viral pathogens. It was established that the «DIA Real Avian Influenza» test kit was capable to detect RNA influenza A virus of high pathogenic H5N1 strains having high sensitivity (100% while RNA of the Crimean HPAI/H5N1 isolate studying and specificity (100% while RNA viruses of Newcastle birds disease, fowl powershift, syndrome of drop in egg production and horse influenza studying.

  20. Potency of whole virus particle and split virion vaccines using dissolving microneedle against challenges of H1N1 and H5N1 influenza viruses in mice.

    Science.gov (United States)

    Nakatsukasa, Akihiro; Kuruma, Koji; Okamatsu, Masatoshi; Hiono, Takahiro; Suzuki, Mizuho; Matsuno, Keita; Kida, Hiroshi; Oyamada, Takayoshi; Sakoda, Yoshihiro

    2017-05-15

    Transdermal vaccination using a microneedle (MN) confers enhanced immunity compared with subcutaneous (SC) vaccination. Here we developed a novel dissolving MN patch for the influenza vaccine. The potencies of split virion and whole virus particle (WVP) vaccines prepared from A/Puerto Rico/8/1934 (H1N1) and A/duck/Hokkaido/Vac-3/2007 (H5N1), respectively, were evaluated. MN vaccination induced higher neutralizing antibody responses than SC vaccination in mice. Moreover, MN vaccination with a lower dose of antigens conferred protective immunity against lethal challenges of influenza viruses than SC vaccination in mice. These results suggest that the WVP vaccines administered using MN are an effective combination for influenza vaccine to be further validated in humans. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Identifikasi Flu Burung H5N1 pada Unggas di Sekitar Kasus Flu Burung pada Manusia Tahun 2011 di Bekasi (AVIAN INFLUENZA H5N1 IDENTIFICATION IN AVIAN SPECIES SURROUNDING AVIAN INFLUENZA H5N1 HUMAN CASES IN BEKASI, WEST JAVA, 2011

    Directory of Open Access Journals (Sweden)

    Dyah Ayu Hewajuli

    2014-05-01

    Full Text Available H5N1 subtype Avian Influenza (AI virus is the causal agent  of AI disease in humans. In Indonesia,the first human AI occurred in Tangerang 2005.  Human AI in Indonesia has now spread into 12 provinces,including West Java, Jakarta, Banten, North Sumatra, East Java, Central Java, Lampung, South Sulawesi,West Sumatra, South Sumatra, Riau, and Bali. Until 2011, the total human AI cases were 182 cases  with150 deaths. This study was conducted to identify of H5N1 AI virus in birds in area surrounding a humanAI human case  in Bekasi city  in March 2011 and to investigate its role in the spread of AI to humans usingmethods of Hemaglutination Inhibition (HI , and Reverse Transcriptase-Polymerase Chain Reaction(RT-PCR. The result showed that 80% of birds in the area surrounding AI  surrounding H5N1 AI humancase in Bekasi 2011 were antibody negative  against  H5N1-AI virus. Antibody against H5N1-AI viruswith the titer less than 4 log 2 was detected in 4.4%  of birds and  with antibody titer 04 4-7 log 2 in 15%of birds. By RT-PCR, H5N1 AI virus was not detected in 47.6% of bird samples. H5 positive and N1negative  AI virus was detected in  30.2% samples.  Only 11.2% samples showed positive for H5N1 AI virus.The results suggest that H5N1-AI virus affecting birds may have a positive role in transmitting to thevirus to human in Bekasi 2011.

  2. Identifying antigenicity-associated sites in highly pathogenic H5N1 influenza virus hemagglutinin by using sparse learning.

    OpenAIRE

    Cai, Zhipeng; Yang, Jialiang; Zhang, Tong; Long, Li-Ping; Boon, Adrianus C; Webby, Richard J; Wan, Xiu-Feng

    2012-01-01

    Since the isolation of A/goose/Guangdong/1/1996 (H5N1) in farmed geese in southern China, highly pathogenic H5N1 avian influenza viruses have posed a continuous threat to both public and animal health. The non-synonymous mutation of the H5 hemagglutinin (HA) gene has resulted in antigenic drift, leading to difficulties in both clinical diagnosis and vaccine strain selection. Characterizing H5N1's antigenic profiles would help resolve these problems. In this study, a novel sparse learning meth...

  3. Continued dominance of pandemic A(H1N1 2009 influenza in Victoria, Australia in 2010

    Directory of Open Access Journals (Sweden)

    James E. Fielding

    2011-08-01

    Full Text Available The 2010 Victorian influenza season was characterized by normal seasonal influenza activity and the dominance of the pandemic A(H1N1 2009 strain. General Practice Sentinel Surveillance rates peaked at 9.4 ILI cases per 1000 consultations in week 36 for metropolitan practices, and at 10.5 ILI cases per 1000 in the following week for rural practices. Of the 678 ILI cases, 23% were vaccinated, a significantly higher percentage than in previous years. A significantly higher percentage of ILI patients were swabbed in 2010 compared to 2003–2008, but similar to 2009, with a similar percentage being positive for influenza as in previous years. Vaccination rates increased with patient age. Melbourne Medical Deputising Service rates peaked in week 35 at 19.1 ILI cases per 1000 consultations. Of the 1914 cases of influenza notified to the Department of Health, Victoria, 1812 (95% were influenza A infections - 1001 (55% pandemic A(H1N1 2009, 4 (<1% A(H3N2 and 807 (45% not subtyped; 88 (5% were influenza B; and 14 (< 1% were influenza A and B co-infections. The World Health Organization Collaborating Centre for Reference and Research on Influenza tested 403 isolates of which 261 were positive for influenza, 250 of which were influenza A and 11 were influenza B. Ninety-two per cent of the influenza A viruses were pandemic A(H1N1 2009, and following antigenic analysis all of these were found to be similar to the current vaccine strain. Three viruses (0.9% were found to be oseltamivir resistant due to an H275Y mutation in the neuraminidase gene.

  4. Protective efficacy of an inactivated Eurasian avian-like H1N1 swine influenza vaccine against homologous H1N1 and heterologous H1N1 and H1N2 viruses in mice.

    Science.gov (United States)

    Sui, Jinyu; Yang, Dawei; Qiao, Chuanling; Xu, Huiyang; Xu, Bangfeng; Wu, Yunpu; Yang, Huanliang; Chen, Yan; Chen, Hualan

    2016-07-19

    Eurasian avian-like H1N1 (EA H1N1) swine influenza viruses are prevalent in pigs in Europe and Asia, but occasionally cause human infection, which raises concern about their pandemic potential. Here, we produced a whole-virus inactivated vaccine with an EA H1N1 strain (A/swine/Guangxi/18/2011, SW/GX/18/11) and evaluated its efficacy against homologous H1N1 and heterologous H1N1 and H1N2 influenza viruses in mice. A strong humoral immune response, which we measured by hemagglutination inhibition (HI) and virus neutralization (VN), was induced in the vaccine-inoculated mice upon challenge. The inactivated SW/GX/18/11 vaccine provided complete protection against challenge with homologous SW/GX/18/11 virus in mice and provided effective protection against challenge with heterologous H1N1 and H1N2 viruses with distinctive genomic combinations. Our findings suggest that this EA H1N1 vaccine can provide protection against both homologous H1N1 and heterologous H1N1 or H1N2 virus infection. As such, it is an excellent vaccine candidate to prevent H1N1 swine influenza. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. In vitro evolution of H5N1 avian influenza virus toward human-type receptor specificity

    DEFF Research Database (Denmark)

    Chen, Li-Mei; Blixt, Klas Ola; Stevens, James

    2012-01-01

    Acquisition of a2-6 sialoside receptor specificity by a2-3 specific highly-pathogenic avian influenza viruses (H5N1) is thought to be a prerequisite for efficient transmission in humans. By in vitro selection for binding a2-6 sialosides, we identified four variant viruses with amino acid....... Unlike the wild type H5N1, this mutant virus was transmitted by direct contact in the ferret model although not by airborne respiratory droplets. However, a reassortant virus with the mutant hemagglutinin, a human N2 neuraminidase and internal genes from an H5N1 virus was partially transmitted via...... respiratory droplets. The complex changes required for airborne transmissibility in ferrets suggest that extensive evolution is needed for H5N1 transmissibility in humans....

  6. Corneal Opacity in Domestic Ducks Experimentally Infected With H5N1 Highly Pathogenic Avian Influenza Virus.

    Science.gov (United States)

    Yamamoto, Y; Nakamura, K; Yamada, M; Mase, M

    2016-01-01

    Domestic ducks can be a key factor in the regional spread of H5N1 highly pathogenic avian influenza (HPAI) virus in Asia. The authors performed experimental infections to examine the relationship between corneal opacity and H5N1 HPAI virus infection in domestic ducks (Anas platyrhyncha var domestica). A total of 99 domestic ducks, including 3 control birds, were used in the study. In experiment 1, when domestic ducks were inoculated intranasally with 2 H5N1 HPAI viruses, corneal opacity appeared more frequently than neurologic signs and mortality. Corneal ulceration and exophthalmos were rare findings. Histopathologic examinations of the eyes of domestic ducks in experiment 2 revealed that corneal opacity was due to the loss of corneal endothelial cells and subsequent keratitis with edema. Influenza viral antigen was detected in corneal endothelial cells and some other ocular cells by immunohistochemistry. Results suggest that corneal opacity is a characteristic and frequent finding in domestic ducks infected with the H5N1 HPAI virus. Confirming this ocular change may improve the detection rate of infected domestic ducks in the field. © The Author(s) 2015.

  7. Efficacy of Live-Attenuated H9N2 Influenza Vaccine Candidates Containing NS1 Truncations against H9N2 Avian Influenza Viruses

    Directory of Open Access Journals (Sweden)

    Sujuan Chen

    2017-06-01

    Full Text Available H9N2 avian influenza virus is a zoonotic agent with a broad host range that can contribute genetic information to H5 or H7N9 subtype viruses, which are significant threats to both humans and birds. Thus, there is a great need for a vaccine to control H9N2 avian influenza. Three mutant viruses of an H9N2 virus A/chicken/Taixing/10/2010 (rTX-NS1-73, rTX-NS1-100, and rTX-NS1-128 were constructed with different NS1 gene truncations and confirmed by western blot analysis. The genetic stability, pathogenicity, transmissibility, and host immune responses toward these mutants were evaluated. The mutant virus rTX-NS1-128 exhibited the most attenuated phenotype and lost transmissibility. The expression levels of interleukin 12 in the nasal and tracheal tissues from chickens immunized with rTX-NS1-128 were significantly upregulated on day 3 post-immunization and the IgA and IgG antibody levels were significantly increased on days 7, 14, and 21 post-immunization when compared to chickens that received an inactivated vaccine. rTX-NS1-128 also protected chickens from challenge by homologous and heterologous H9N2 avian influenza viruses. The results indicate that rTX-NS1-128 can be used as a potential live-attenuated vaccine against H9N2 avian influenza.

  8. Spatiotemporal Structure of Molecular Evolution of H5N1 Highly Pathogenic Avian Influenza Viruses in Vietnam

    OpenAIRE

    Carrel, Margaret A.; Emch, Michael; Jobe, R. Todd; Moody, Aaron; Wan, Xiu-Feng

    2010-01-01

    Background Vietnam is one of the countries most affected by outbreaks of H5N1 highly pathogenic avian influenza viruses. First identified in Vietnam in poultry in 2001 and in humans in 2004, the virus has since caused 111 cases and 56 deaths in humans. In 2003/2004 H5N1 outbreaks, nearly the entire poultry population of Vietnam was culled. Our earlier study (Wan et al., 2008, PLoS ONE, 3(10): e3462) demonstrated that there have been at least six independent H5N1 introductions into Vietnam and...

  9. Identifying antigenicity associated sites in highly pathogenic H5N1 influenza virus hemagglutinin by using sparse learning

    OpenAIRE

    Cai, Zhipeng; Ducatez, Mariette F.; Yang, Jialiang; Zhang, Tong; Long, Li-Ping; Boon, Adrianus C.; Webby, Richard J.; Wan, Xiu-Feng

    2012-01-01

    Since the isolation of A/goose/Guangdong/1/1996 (H5N1) in farmed geese in southern China, highly pathogenic H5N1 avian influenza viruses have posed a continuous threat to both public and animal health. The non-synonymous mutation of the H5 hemagglutinin gene has resulted in antigenic drift, leading to difficulties in both clinical diagnosis and vaccine strain selection. Characterizing H5N1’s antigenic profiles would help resolve these problems. In this study, a novel sparse learning method wa...

  10. Identification of reassortant pandemic H1N1 influenza virus in Korean pigs.

    Science.gov (United States)

    Han, Jae Yeon; Park, Sung Jun; Kim, Hye Kwon; Rho, Semi; Nguyen, Giap Van; Song, Daesub; Kang, Bo Kyu; Moon, Hyung Jun; Yeom, Min Joo; Park, Bong Kyun

    2012-05-01

    Since the 2009 pandemic human H1N1 influenza A virus emerged in April 2009, novel reassortant strains have been identified throughout the world. This paper describes the detection and isolation of reassortant strains associated with human pandemic influenza H1N1 and swine influenza H1N2 (SIV) viruses in swine populations in South Korea. Two influenza H1N2 reassortants were detected, and subtyped by PCR. The strains were isolated using Madin- Darby canine kidney (MDCK) cells, and genetically characterized by phylogenetic analysis for genetic diversity. They consisted of human, avian, and swine virus genes that were originated from the 2009 pandemic H1N1 virus and a neuraminidase (NA) gene from H1N2 SIV previously isolated in North America. This identification of reassortment events in swine farms raises concern that reassortant strains may continuously circulate within swine populations, calling for the further study and surveillance of pandemic H1N1 among swine.

  11. Novel triple reassortant H1N2 influenza viruses bearing six internal genes of the pandemic 2009/H1N1 influenza virus were detected in pigs in China.

    Science.gov (United States)

    Qiao, Chuanling; Liu, Liping; Yang, Huanliang; Chen, Yan; Xu, Huiyang; Chen, Hualan

    2014-12-01

    The pandemic A/H1N1 influenza viruses emerged in both Mexico and the United States in March 2009, and were transmitted efficiently in the human population. Transmissions of the pandemic 2009/H1N1 virus from humans to poultry and other species of mammals were reported from several continents during the course of the 2009 H1N1 pandemic. Reassortant H1N1, H1N2, and H3N2 viruses containing genes of the pandemic 2009/H1N1 viruses appeared in pigs in some countries. In winter of 2012, a total of 2600 nasal swabs were collected from healthy pigs in slaughterhouses located throughout 10 provinces in China. The isolated viruses were subjected to genetic and antigenic analysis. Two novel triple-reassortant H1N2 influenza viruses were isolated from swine in China in 2012, with the HA gene derived from Eurasian avian-like swine H1N1, the NA gene from North American swine H1N2, and the six internal genes from the pandemic 2009/H1N1 viruses. The two viruses had similar antigenic features and some significant changes in antigenic characteristics emerged when compared to the previously identified isolates. We inferred that the novel reassortant viruses in China may have arisen from the accumulation of the three types of influenza viruses, which further indicates that swine herds serve as "mixing vessels" for influenza viruses. Influenza virus reassortment is an ongoing process, and our findings highlight the urgent need for continued influenza surveillance among swine herds. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Isolation and identification of highly pathogenic avian influenza virus subtype H5N1 in peafowl (Pavo cristatus).

    Science.gov (United States)

    Ismail, Mahmoud Moussa; Khan, Owais Ahmed; Cattoli, Giovanni; Lu, Huaguang

    2010-03-01

    An outbreak of highly pathogenic avian influenza (HPAI) virus subtype H5N1 was first diagnosed in a "backyard" flock of peafowl (Pavo cristatus) raised on palace premises in the Kingdom of Saudi Arabia in December 3, 2007. The flock consisted of 40 peafowl, and their ages ranged from 3 to 5 years old. Affected birds suffered from depression, anorexia, and white diarrhea. Four dead birds were submitted for HPAI diagnosis at the Central Veterinary Diagnostic Laboratory in Riyadh. Brain and liver tissues and tracheal and cloacal swabs were taken from the dead birds and processed for a real-time reverse transcriptase (RT)-PCR test and virus isolation in specific-pathogen-free embryonating chicken eggs. The H5N1 subtype of avian influenza virus was isolated from the four dead birds and identified by a real-time RT-PCR before and after egg inoculation. The virus isolates were characterized as HPAI H5N1 virus by sequencing analysis. Phylogenetic comparisons revealed that the H5N1 viruses isolated from peafowl belong to the genetic clade 2.2 according to the World Health Organization nomenclature. The peafowl H5N1 virus falls into 2.2.2 sublineage II and clusters with the H5N1 viruses isolated from poultry in Saudi Arabia in 2007-08.

  13. Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus

    NARCIS (Netherlands)

    Xu, Yanjie; Gong, Peng; Wielstra, Ben; Si, Yali

    2016-01-01

    The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration

  14. Dual Infection of Novel Influenza Viruses A/H1N1 and A/H3N2 in a Cluster of Cambodian Patients

    Science.gov (United States)

    2011-01-01

    influenza viruses as well as the avian influenza virus A/H5N1...on full genome sequencing. This incident confirms dual influenza virus infections and highlights the risk of zoonotic and seasonal influenza viruses ...North American swine influenza viruses , North American avian influenza viruses , human influenza viruses , and a Eurasian swine influenza virus . 18

  15. Vaccination with recombinant RNA replicon particles protects chickens from H5N1 highly pathogenic avian influenza virus.

    Directory of Open Access Journals (Sweden)

    Stefan J Halbherr

    Full Text Available Highly pathogenic avian influenza viruses (HPAIV of subtype H5N1 not only cause a devastating disease in domestic chickens and turkeys but also pose a continuous threat to public health. In some countries, H5N1 viruses continue to circulate and evolve into new clades and subclades. The rapid evolution of these viruses represents a problem for virus diagnosis and control. In this work, recombinant vesicular stomatitis virus (VSV vectors expressing HA of subtype H5 were generated. To comply with biosafety issues the G gene was deleted from the VSV genome. The resulting vaccine vector VSV*ΔG(HA was propagated on helper cells providing the VSV G protein in trans. Vaccination of chickens with a single intramuscular dose of 2×10⁸ infectious replicon particles without adjuvant conferred complete protection from lethal H5N1 infection. Subsequent application of the same vaccine strongly boosted the humoral immune response and completely prevented shedding of challenge virus and transmission to sentinel birds. The vaccine allowed serological differentiation of infected from vaccinated animals (DIVA by employing a commercially available ELISA. Immunized chickens produced antibodies with neutralizing activity against multiple H5 viruses representing clades 1, 2.2, 2.5, and low-pathogenic avian influenza viruses (classical clade. Studies using chimeric H1/H5 hemagglutinins showed that the neutralizing activity was predominantly directed against the globular head domain. In summary, these results suggest that VSV replicon particles are safe and potent DIVA vaccines that may help to control avian influenza viruses in domestic poultry.

  16. Genetic Characterization of Continually Evolving Highly Pathogenic H5N6 Influenza Viruses in China, 2012-2016.

    Science.gov (United States)

    Li, Meng; Zhao, Na; Luo, Jing; Li, Yuan; Chen, Lin; Ma, Jiajun; Zhao, Lin; Yuan, Guohui; Wang, Chengmin; Wang, Yutian; Liu, Yanhua; He, Hongxuan

    2017-01-01

    H5N6 is a highly pathogenic avian influenza (HPAI) and a zoonotic disease that causes recurring endemics in East Asia. At least 155 H5N6 outbreaks, including 15 human infections, have been reported in China. These repeated outbreaks have increased concern that the H5N6 virus may cross over to humans and cause a pandemic. In February, 2016, peafowls in a breeding farm exhibited a highly contagious disease. Post-mortem examinations, including RT-PCR, and virus isolation, confirmed that the highly pathogenic H5N6 influenza virus was the causative agent, and the strain was named A/ Pavo Cristatus /Jiangxi/JA1/2016. In animal experiments, it exhibited high pathogenicity in chickens and an estimated median lethal dose in mice of ~10 4.3 TCID 50 . A phylogenetic analysis showed that JA1/2016 was clustered in H5 clade 2.3.4.4. FG594-like H5N6 virus from Guangdong Province was the probable predecessor of JA1/2016, and the estimated divergence time was June 2014. Furthermore, we found that H5N6 influenza viruses can be classified into the two following groups: Group 1 and Group 2. Group 2 influenza viruses have not been detected since the end of 2014, whereas Group 1 influenza viruses have continually evolved and reassorted with the "gene pool" circulating in south China, resulting in the rise of novel subtypes of this influenza virus. An increase in the number of its identified hosts, the expanding range of its distribution, and the continual evolution of H5N6 AIVs enhance the risk that an H5N6 virus may spread to other continents and cause a pandemic.

  17. Viral and Host Factors Required for Avian H5N1 Influenza A Virus Replication in Mammalian Cells

    Directory of Open Access Journals (Sweden)

    Hong Zhang

    2013-06-01

    Full Text Available Following the initial and sporadic emergence into humans of highly pathogenic avian H5N1 influenza A viruses in Hong Kong in 1997, we have come to realize the potential for avian influenza A viruses to be transmitted directly from birds to humans. Understanding the basic viral and cellular mechanisms that contribute to infection of mammalian species with avian influenza viruses is essential for developing prevention and control measures against possible future human pandemics. Multiple physical and functional cellular barriers can restrict influenza A virus infection in a new host species, including the cell membrane, the nuclear envelope, the nuclear environment, and innate antiviral responses. In this review, we summarize current knowledge on viral and host factors required for avian H5N1 influenza A viruses to successfully establish infections in mammalian cells. We focus on the molecular mechanisms underpinning mammalian host restrictions, as well as the adaptive mutations that are necessary for an avian influenza virus to overcome them. It is likely that many more viral and host determinants remain to be discovered, and future research in this area should provide novel and translational insights into the biology of influenza virus-host interactions.

  18. Comparative pathogenesis of an avian H5N2 and a swine H1N1 influenza virus in pigs.

    Directory of Open Access Journals (Sweden)

    Annebel De Vleeschauwer

    2009-08-01

    Full Text Available Pigs are considered intermediate hosts for the transmission of avian influenza viruses (AIVs to humans but the basic organ pathogenesis of AIVs in pigs has been barely studied. We have used 42 four-week-old influenza naive pigs and two different inoculation routes (intranasal and intratracheal to compare the pathogenesis of a low pathogenic (LP H5N2 AIV with that of an H1N1 swine influenza virus. The respiratory tract and selected extra-respiratory tissues were examined for virus replication by titration, immunofluorescence and RT-PCR throughout the course of infection. Both viruses caused a productive infection of the entire respiratory tract and epithelial cells in the lungs were the major target. Compared to the swine virus, the AIV produced lower virus titers and fewer antigen positive cells at all levels of the respiratory tract. The respiratory part of the nasal mucosa in particular showed only rare AIV positive cells and this was associated with reduced nasal shedding of the avian compared to the swine virus. The titers and distribution of the AIV varied extremely between individual pigs and were strongly affected by the route of inoculation. Gross lung lesions and clinical signs were milder with the avian than with the swine virus, corresponding with lower viral loads in the lungs. The brainstem was the single extra-respiratory tissue found positive for virus and viral RNA with both viruses. Our data do not reject the theory of the pig as an intermediate host for AIVs, but they suggest that AIVs need to undergo genetic changes to establish full replication potential in pigs. From a biomedical perspective, experimental LP H5 AIV infection of pigs may be useful to examine heterologous protection provided by H5 vaccines or other immunization strategies, as well as for further studies on the molecular pathogenesis and neurotropism of AIVs in mammals.

  19. A comparison between spray drying and spray freeze drying to produce an influenza subunit vaccine powder for inhalation

    NARCIS (Netherlands)

    Saluja, V.; Amorij, J-P.; Kapteyn, J. C.; de Boer, A. H.; Frijlink, H. W.; Hinrichs, W. L. J.

    2010-01-01

    The aim of this study was to investigate two different processes to produce a stable influenza subunit vaccine powder for pulmonary immunization i.e. spray drying (SD) and spray freeze drying (SFD). The formulations were analyzed by proteolytic assay, single radial immunodiffusion assay (SRID),

  20. Isolation and genetic characterization of avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China.

    Science.gov (United States)

    Yu, Hai; Zhang, Peng-Chao; Zhou, Yan-Jun; Li, Guo-Xin; Pan, Jie; Yan, Li-Ping; Shi, Xiao-Xiao; Liu, Hui-Li; Tong, Guang-Zhi

    2009-08-21

    As pigs are susceptible to both human and avian influenza viruses, they have been proposed to be intermediate hosts or mixing vessels for the generation of pandemic influenza viruses through reassortment or adaptation to the mammalian host. In this study, we reported avian-like H1N1 and novel ressortant H1N2 influenza viruses from pigs in China. Homology and phylogenetic analyses showed that the H1N1 virus (A/swine/Zhejiang/1/07) was closely to avian-like H1N1 viruses and seemed to be derived from the European swine H1N1 viruses, which was for the first time reported in China; and the two H1N2 viruses (A/swine/Shanghai/1/07 and A/swine/Guangxi/13/06) were novel ressortant H1N2 influenza viruses containing genes from the classical swine (HA, NP, M and NS), human (NA and PB1) and avian (PB2 and PA) lineages, which indicted that the reassortment among human, avian, and swine influenza viruses had taken place in pigs in China and resulted in the generation of new viruses. The isolation of avian-like H1N1 influenza virus originated from the European swine H1N1 viruses, especially the emergence of two novel ressortant H1N2 influenza viruses provides further evidence that pigs serve as intermediate hosts or "mixing vessels", and swine influenza virus surveillance in China should be given a high priority.

  1. H5N1 Influenza A Virus PB1-F2 Relieves HAX-1-Mediated Restriction of Avian Virus Polymerase PA in Human Lung Cells.

    Science.gov (United States)

    Mazel-Sanchez, B; Boal-Carvalho, I; Silva, F; Dijkman, R; Schmolke, M

    2018-06-01

    Highly pathogenic influenza A viruses (IAV) from avian hosts were first reported to directly infect humans 20 years ago. However, such infections are rare events, and our understanding of factors promoting or restricting zoonotic transmission is still limited. One accessory protein of IAV, PB1-F2, was associated with pathogenicity of pandemic and zoonotic IAV. This short (90-amino-acid) peptide does not harbor an enzymatic function. We thus identified host factors interacting with H5N1 PB1-F2, which could explain its importance for virulence. PB1-F2 binds to HCLS1-associated protein X1 (HAX-1), a recently identified host restriction factor of the PA subunit of IAV polymerase complexes. We demonstrate that the PA of a mammal-adapted H1N1 IAV is resistant to HAX-1 imposed restriction, while the PA of an avian-origin H5N1 IAV remains sensitive. We also showed HAX-1 sensitivity for PAs of A/Brevig Mission/1/1918 (H1N1) and A/Shanghai/1/2013 (H7N9), two avian-origin zoonotic IAV. Inhibition of H5N1 polymerase by HAX-1 can be alleviated by its PB1-F2 through direct competition. Accordingly, replication of PB1-F2-deficient H5N1 IAV is attenuated in the presence of large amounts of HAX-1. Mammal-adapted H1N1 and H3N2 viruses do not display this dependence on PB1-F2 for efficient replication in the presence of HAX-1. We propose that PB1-F2 plays a key role in zoonotic transmission of avian H5N1 IAV into humans. IMPORTANCE Aquatic and shore birds are the natural reservoir of influenza A viruses from which the virus can jump into a variety of bird and mammal host species, including humans. H5N1 influenza viruses are a good model for this process. They pose an ongoing threat to human and animal health due to their high mortality rates. However, it is currently unclear what restricts these interspecies jumps on the host side or what promotes them on the virus side. Here we show that a short viral peptide, PB1-F2, helps H5N1 bird influenza viruses to overcome a human restriction

  2. Influenza A H5N1 immigration is filtered out at some international borders.

    Directory of Open Access Journals (Sweden)

    Robert G Wallace

    2008-02-01

    Full Text Available Geographic spread of highly pathogenic influenza A H5N1, the bird flu strain, appears a necessary condition for accelerating the evolution of a related human-to-human infection. As H5N1 spreads the virus diversifies in response to the variety of socioecological environments encountered, increasing the chance a human infection emerges. Genetic phylogenies have for the most part provided only qualitative evidence that localities differ in H5N1 diversity. For the first time H5N1 variation is quantified across geographic space.We constructed a statistical phylogeography of 481 H5N1 hemagglutinin genetic sequences from samples collected across 28 Eurasian and African localities through 2006. The MigraPhyla protocol showed southern China was a source of multiple H5N1 strains. Nested clade analysis indicated H5N1 was widely dispersed across southern China by both limited dispersal and long distance colonization. The UniFrac metric, a measure of shared phylogenetic history, grouped H5N1 from Indonesia, Japan, Thailand and Vietnam with those from southeastern Chinese provinces engaged in intensive international trade. Finally, H5N1's accumulative phylogenetic diversity was greatest in southern China and declined beyond. The gradient was interrupted by areas of greater and lesser phylogenetic dispersion, indicating H5N1 migration was restricted at some geopolitical borders. Thailand and Vietnam, just south of China, showed significant phylogenetic clustering, suggesting newly invasive H5N1 strains have been repeatedly filtered out at their northern borders even as both countries suffered recurring outbreaks of endemic strains. In contrast, Japan, while successful in controlling outbreaks, has been subjected to multiple introductions of the virus.The analysis demonstrates phylogenies can provide local health officials with more than hypotheses about relatedness. Pathogen dispersal, the functional relationships among disease ecologies across localities, and

  3. Memory T cells established by seasonal human influenza A infection cross-react with avian influenza A (H5N1) in healthy individuals

    NARCIS (Netherlands)

    Lee, Laurel Yong-Hwa; Anh, Ha Do Lien; Simmons, Cameron; de Jong, Menno D.; Chau, Nguyen Van Vinh; Schumacher, Reto; Peng, Yan Chun; McMichael, Andrew J.; Farrar, Jeremy J.; Smith, Geoffrey L.; Townsend, Alain R. M.; Askonas, Brigitte A.; Rowland-Jones, Sarah; Dong, Tao

    2008-01-01

    The threat of avian influenza A (H5N1) infection in humans remains a global health concern. Current influenza vaccines stimulate antibody responses against the surface glycoproteins but are ineffective against strains that have undergone significant antigenic variation. An alternative approach is to

  4. Viremia associated with fatal outcomes in ferrets infected with avian H5N1 influenza virus.

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    Xue Wang

    Full Text Available Avian H5N1 influenza viruses cause severe disease and high mortality in infected humans. However, tissue tropism and underlying pathogenesis of H5N1 virus infection in humans needs further investigation. The objective of this work was to study viremia, tissue tropism and disease pathogenesis of H5N1 virus infection in the susceptible ferret animal model. To evaluate the relationship of morbidity and mortality with virus loads, we performed studies in ferrets infected with the H5N1 strain A/VN/1203/04 to assess clinical signs after infection and virus load in lung, brain, ileum, nasal turbinate, nasal wash, and blood. We observed that H5N1 infection in ferrets is characterized by high virus load in the brain and and low levels in the ileum using real-time PCR. In addition, viral RNA was frequently detected in blood one or two days before death and associated with symptoms of diarrhea. Our observations further substantiate pathogenicity of H5N1 and further indicate that viremia may be a bio-marker for fatal outcomes in H5N1 infection.

  5. H5N1-SeroDetect EIA and rapid test: a novel differential diagnostic assay for serodiagnosis of H5N1 infections and surveillance.

    Science.gov (United States)

    Khurana, Surender; Sasono, Pretty; Fox, Annette; Nguyen, Van Kinh; Le, Quynh Mai; Pham, Quang Thai; Nguyen, Tran Hien; Nguyen, Thanh Liem; Horby, Peter; Golding, Hana

    2011-12-01

    Continuing evolution of highly pathogenic (HP) H5N1 influenza viruses in wild birds with transmission to domestic poultry and humans poses a pandemic threat. There is an urgent need for a simple and rapid serological diagnostic assay which can differentiate between antibodies to seasonal and H5N1 strains and that could provide surveillance tools not dependent on virus isolation and nucleic acid technologies. Here we describe the establishment of H5N1 SeroDetect enzyme-linked immunosorbent assay (ELISA) and rapid test assays based on three peptides in HA2 (488-516), PB1-F2 (2-75), and M2e (2-24) that are highly conserved within H5N1 strains. These peptides were identified by antibody repertoire analyses of H5N1 influenza survivors in Vietnam using whole-genome-fragment phage display libraries (GFPDLs). To date, both platforms have demonstrated high levels of sensitivity and specificity in detecting H5N1 infections (clade 1 and clade 2.3.4) in Vietnamese patients as early as 7 days and up to several years postinfection. H5N1 virus-uninfected individuals in Vietnam and the United States, including subjects vaccinated with seasonal influenza vaccines or with confirmed seasonal virus infections, did not react in the H5N1-SeroDetect assays. Moreover, sera from individuals vaccinated with H5N1 subunit vaccine with moderate anti-H5N1 neutralizing antibody titers did not react positively in the H5N1-SeroDetect ELISA or rapid test assays. The simple H5N1-SeroDetect ELISA and rapid tests could provide an important tool for large-scale surveillance for potential exposure to HP H5N1 strains in both humans and birds.

  6. Evolution of highly pathogenic H5N1 avian influenza viruses in Vietnam between 2001 and 2007.

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    Xiu-Feng Wan

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 viruses have caused dramatic economic losses to the poultry industry of Vietnam and continue to pose a serious threat to public health. As of June 2008, Vietnam had reported nearly one third of worldwide laboratory confirmed human H5N1 infections. To better understand the emergence, spread and evolution of H5N1 in Vietnam we studied over 300 H5N1 avian influenza viruses isolated from Vietnam since their first detection in 2001. Our phylogenetic analyses indicated that six genetically distinct H5N1 viruses were introduced into Vietnam during the past seven years. The H5N1 lineage that evolved following the introduction in 2003 of the A/duck/Hong Kong/821/2002-like viruses, with clade 1 hemagglutinin (HA, continued to predominate in southern Vietnam as of May 2007. A virus with a clade 2.3.4 HA newly introduced into northern Vietnam in 2007, reassorted with pre-existing clade 1 viruses, resulting in the emergence of novel genotypes with neuraminidase (NA and/or internal gene segments from clade 1 viruses. A total of nine distinct genotypes have been present in Vietnam since 2001, including five that were circulating in 2007. At least four of these genotypes appear to have originated in Vietnam and represent novel H5N1 viruses not reported elsewhere. Geographic and temporal analyses of H5N1 infection dynamics in poultry suggest that the majority of viruses containing new genes were first detected in northern Vietnam and subsequently spread to southern Vietnam after reassorting with pre-existing local viruses in northern Vietnam. Although the routes of entry and spread of H5N1 in Vietnam remain speculative, enhanced poultry import controls and virologic surveillance efforts may help curb the entry and spread of new HPAI viral genes.

  7. The Influenza Virus and the 2009 H1N1 Outbreak

    Science.gov (United States)

    2016-04-08

    MDW/SGVU SUBJECT: Professional Presentation Approval 8 APR 2016 1. Your paper, entitled The Influenza Virus and the 2009 HlNl Outbreak presented at...L TO BE PUBLISHED OR PRESENTED The Influenza Virus and the 2009 H1N1 Outbreak 2. FUNDING RECEIVED FOR THIS STUDY? DYES [g] NO FUNDING SOURCE: I I...336:!. ~~ 2 C-; MARKE. COON. :vtajor. USAF Acting Chic!’. Civil I.aw The Influenza Virus and the 2009 H 1 N 1 Outbreak Thomas. F. Gibbons, Ph.D

  8. Highly pathogenic avian influenza virus (H5N1) isolated from whooper swans, Japan.

    Science.gov (United States)

    Uchida, Yuko; Mase, Masaji; Yoneda, Kumiko; Kimura, Atsumu; Obara, Tsuyoshi; Kumagai, Seikou; Saito, Takehiko; Yamamoto, Yu; Nakamura, Kikuyasu; Tsukamoto, Kenji; Yamaguchi, Shigeo

    2008-09-01

    On April 21, 2008, four whooper swans were found dead at Lake Towada, Akita prefecture, Japan. Highly pathogenic avian influenza virus of the H5N1 subtype was isolated from specimens of the affected birds. The hemagglutinin (HA) gene of the isolate belongs to clade 2.3.2 in the HA phylogenetic tree.

  9. Generation, characterization and epitope mapping of two neutralizing and protective human recombinant antibodies against influenza A H5N1 viruses.

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    Lina Sun

    Full Text Available BACKGROUND: The development of new therapeutic targets and strategies to control highly pathogenic avian influenza (HPAI H5N1 virus infection in humans is urgently needed. Broadly cross-neutralizing recombinant human antibodies obtained from the survivors of H5N1 avian influenza provide an important role in immunotherapy for human H5N1 virus infection and definition of the critical epitopes for vaccine development. METHODOLOGY/PRINCIPAL FINDINGS: We have characterized two recombinant baculovirus-expressed human antibodies (rhAbs, AVFluIgG01 and AVFluIgG03, generated by screening a Fab antibody phage library derived from a patient recovered from infection with a highly pathogenic avian influenza A H5N1 clade 2.3 virus. AVFluIgG01 cross-neutralized the most of clade 0, clade 1, and clade 2 viruses tested, in contrast, AVFluIgG03 only neutralized clade 2 viruses. Passive immunization of mice with either AVFluIgG01 or AVFluIgG03 antibody resulted in protection from a lethal H5N1 clade 2.3 virus infection. Furthermore, through epitope mapping, we identify two distinct epitopes on H5 HA molecule recognized by these rhAbs and demonstrate their potential to protect against a lethal H5N1 virus infection in a mouse model. CONCLUSIONS/SIGNIFICANCE: Importantly, localization of the epitopes recognized by these two neutralizing and protective antibodies has provided, for the first time, insight into the human antibody responses to H5N1 viruses which contribute to the H5 immunity in the recovered patient. These results highlight the potential of a rhAbs treatment strategy for human H5N1 virus infection and provide new insight for the development of effective H5N1 pandemic vaccines.

  10. Highly pathogenic influenza A(H5N1 virus survival in complex artificial aquatic biotopes.

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    Viseth Srey Horm

    Full Text Available BACKGROUND: Very little is known regarding the persistence of Highly Pathogenic Avian Influenza (HPAI H5N1 viruses in aquatic environments in tropical countries, although environmental materials have been suggested to play a role as reservoirs and sources of transmission for H5N1 viruses. METHODOLOGY/PRINCIPAL FINDINGS: The survival of HPAI H5N1 viruses in experimental aquatic biotopes (water, mud, aquatic flora and fauna relevant to field conditions in Cambodia was investigated. Artificial aquatic biotopes, including simple ones containing only mud and water, and complex biotopes involving the presence of aquatic flora and fauna, were set up. They were experimentally contaminated with H5N1 virus. The persistence of HPAI H5N1 virus (local avian and human isolates was determined by virus isolation in embryonated chicken eggs and by real-time reverse-polymerase chain reaction. Persistence of infectious virus did not exceed 4 days, and was only identified in rain water. No infectious virus particles were detected in pond and lake water or mud even when high inoculum doses were used. However, viral RNA persisted up to 20 days in rain water and 7 days in pond or lake water. Viral RNA was also detected in mud samples, up to 14 days post-contamination in several cases. Infectious virus and viral RNA was detected in few cases in the aquatic fauna and flora, especially in bivalves and labyrinth fish, although these organisms seemed to be mostly passive carriers of the virus rather than host allowing virus replication. CONCLUSIONS/SIGNIFICANCE: Although several factors for the survival and persistence of HPAI viruses in the environment are still to be elucidated, and are particularly hard to control in laboratory conditions, our results, along with previous data, support the idea that environmental surveillance is of major relevance for avian influenza control programs.

  11. Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico

    Science.gov (United States)

    Comas‐García, Andreu; García‐Sepúlveda, Christian A.; Méndez‐de Lira, José J.; Aranda‐Romo, Saray; Hernández‐Salinas, Alba E.; Noyola, Daniel E.

    2010-01-01

    Please cite this paper as: Comas‐García et al. (2011) Mortality attributable to pandemic influenza A (H1N1) 2009 in San Luis Potosí, Mexico. Influenza and Other Respiratory Viruses 5(2), 76–82. Background  Acute respiratory infections are a leading cause of morbidity and mortality worldwide. Starting in 2009, pandemic influenza A(H1N1) 2009 virus has become one of the leading respiratory pathogens worldwide. However, the overall impact of this virus as a cause of mortality has not been clearly defined. Objectives  To determine the impact of pandemic influenza A(H1N1) 2009 on mortality in a Mexican population. Methods  We assessed the impact of pandemic influenza virus on mortality during the first and second outbreaks in San Luis Potosí, Mexico, and compared it to mortality associated with seasonal influenza and respiratory syncytial virus (RSV) during the previous winter seasons. Results  We estimated that, on average, 8·1% of all deaths that occurred during the 2003–2009 seasons were attributable to influenza and RSV. During the first pandemic influenza A(H1N1) 2009 outbreak, there was an increase in mortality in persons 5–59 years of age, but not during the second outbreak (Fall of 2009). Overall, pandemic influenza A (H1N1) 2009 outbreaks had similar effects on mortality to those associated with seasonal influenza virus epidemics. Conclusions  The impact of influenza A(H1N1) 2009 virus on mortality during the first year of the pandemic was similar to that observed for seasonal influenza. The establishment of real‐time surveillance systems capable of integrating virological, morbidity, and mortality data may result in the timely identification of outbreaks so as to allow for the institution of appropriate control measures to reduce the impact of emerging pathogens on the population. PMID:21306570

  12. Conocimientos, actitudes y prácticas sobre la influenza A(H1N1 2009 y la vacunación contra influenza pandémica: resultados de una encuesta poblacional Knowledge, attitudes and practices about influenza A(H1N1 2009, and influenza vaccine in Mexico: results of a population survey

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    María Eugenia Jiménez-Corona

    2012-12-01

    Full Text Available OBJETIVO: Evaluar conocimientos, actitudes y prácticas respecto a la pandemia de influenza, con especial énfasis en la vacuna contra influenza estacional y pandémica. MATERIAL Y MÉTODOS: Estudio transversal con muestreo polietápico probabilístico, realizado durante diciembre de 2009 en residentes mayores de 18 años de la Ciudad de México (y área metropolitana, Monterrey, Guadalajara y Mérida. RESULTADOS: Se incluyeron 1 600 sujetos (48.9% masculino; 34% había recibido vacuna contra influenza estacional en años pasados, 90.6% estaba dispuesto a recibir la vacuna contra A(H1N1. La principal causa de rechazo a la vacunación fue no confiar en la vacuna (46.5%. Principales medidas preventivas identificadas por los encuestados: lavado de manos (47.5%, vacuna contra A(H1N1 (28% y etiqueta respiratoria (19.4%. El nivel escolar (1.7, p=0.006 y edad (1.02, pOBJECTIVE: To assess knowledge, attitudes and practices regarding influenza pandemic, with special emphasis on issues related to influenza vaccine, seasonal and pandemic. MATERIALS AND METHODS: Cross-sectional study, probabilistic multistage sampling in patients over 18 years, residents of Mexico City (and metropolitan area, Monterrey, Guadalajara and Merida in December 2009. RESULTS: A total of 1.600 subjects (48.9% male were interviewed, 34% had previously received seasonal flu vaccine, 90.6% were willing to be vaccinated against A(H1N1, 46.5% of those who would not receive the vaccine was because they did not trust A (H1N1, 68% considered influenza A (H1N1 as a risk for their family. Hand washing was the preventive measure most commonly reported (47.5%, secondly influenza vaccine (28%. Schooling (1.7, p=0.006 and age (1.02, p<0.001 influence rejection to get vaccine. 82.9% of respondents rate the federal government's management as good or very good. CONCLUSIONS: There was a high acceptance rate for the pandemic influenza vaccine in Mexico when compared to similar studies in other

  13. Natural Reassortants of Potentially Zoonotic Avian Influenza Viruses H5N1 and H9N2 from Egypt Display Distinct Pathogenic Phenotypes in Experimentally Infected Chickens and Ferrets.

    Science.gov (United States)

    Naguib, Mahmoud M; Ulrich, Reiner; Kasbohm, Elisa; Eng, Christine L P; Hoffmann, Donata; Grund, Christian; Beer, Martin; Harder, Timm C

    2017-12-01

    The cocirculation of zoonotic highly pathogenic avian influenza virus (HPAIV) of subtype H5N1 and avian influenza virus (AIV) of subtype H9N2 among poultry in Egypt for at least 6 years should render that country a hypothetical hot spot for the emergence of reassortant, phenotypically altered viruses, yet no reassortants have been detected in Egypt. The present investigations proved that reassortants of the Egyptian H5N1 clade 2.2.1.2 virus and H9N2 virus of the G1-B lineage can be generated by coamplification in embryonated chicken eggs. Reassortants were restricted to the H5N1 subtype and acquired between two and all six of the internal segments of the H9N2 virus. Five selected plaque-purified reassortant clones expressed a broad phenotypic spectrum both in vitro and in vivo Two groups of reassortants were characterized to have retarded growth characteristics in vitro compared to the H5N1 parent virus. One clone provoked reduced mortality in inoculated chickens, although the characteristics of a highly pathogenic phenotype were retained. Enhanced zoonotic properties were not predicted for any of these clones, and this prediction was confirmed by ferret inoculation experiments: neither the H5N1 parent virus nor two selected clones induced severe clinical symptoms or were transmitted to sentinel ferrets by contact. While the emergence of reassortants of Egyptian HPAIV of subtype H5N1 with internal gene segments of cocirculating H9N2 viruses is possible in principle, the spread of such viruses is expected to be governed by their fitness to outcompete the parental viruses in the field. The eventual spread of attenuated phenotypes, however, would negatively impact syndrome surveillance on poultry farms and might foster enzootic virus circulation. IMPORTANCE Despite almost 6 years of the continuous cocirculation of highly pathogenic avian influenza virus H5N1 and avian influenza virus H9N2 in poultry in Egypt, no reassortants of the two subtypes have been reported

  14. Unique Infectious Strategy of H5N1 Avian Influenza Virus Is Governed by the Acid-Destabilized Property of Hemagglutinin.

    Science.gov (United States)

    Daidoji, Tomo; Watanabe, Yohei; Arai, Yasuha; Kajikawa, Junichi; Hirose, Ryohei; Nakaya, Takaaki

    Highly pathogenic avian influenza (HPAI) H5N1 virus emerged in 1997 as a zoonotic disease in Hong Kong. It has since spread to Asia and Europe and is a serious threat to both the poultry industry and human health. For effective surveillance and possible prevention/control of HPAI H5N1 viruses, it is necessary to understand the molecular mechanism underlying HPAI H5N1 pathogenesis. The hemagglutinin (HA) protein of influenza A viruses (IAVs) is one of the major determinants of host adaptation, transmissibility, and viral virulence. The main function of the HA protein is to facilitate viral entry and viral genome release within host cells before infection. To achieve viral infection, IAVs belonging to different subtypes or strains induce viral-cell membrane fusion at different endosomal pH levels after internalization through endocytosis. However, host-specific endosomal pH also affects induction of membrane fusion followed by infection. The HA protein of HPAI H5N1 has a higher pH threshold for membrane fusion than the HA protein of classical avian influenza viruses. Although this particular property of HA (which governs viral infection) is prone to deactivation in the avian intestine or in an ambient environment, it facilitates efficient infection of host cells, resulting in a broad host tropism, regardless of the pH in the host endosome. Accumulated knowledge, together with further research, about the HA-governed mechanism underlying HPAI H5N1 virulence (i.e., receptor tropism and pH-dependent viral-cell membrane fusion) will be helpful for developing effective surveillance strategies and for prevention/control of HPAI H5N1 infection.

  15. Effectiveness of A(H1N1)pdm09 influenza vaccine in adults recommended for annual influenza vaccination.

    NARCIS (Netherlands)

    Gefenaite, G.; Tacken, M.; Bos, J.; Stirbu-Wagner, I.; Korevaar, J.C.; Stolk, R.P.; Wolters, B.; Bijl, M.; Postma, M.J.; Wilschut, J.; Nichol, K.L.; Hak, E.

    2013-01-01

    Introduction: Because of variability in published A(H1N1)pdm09 influenza vaccine effectiveness estimates, we conducted a study in the adults belonging to the risk groups to assess the A(H1N1)pdm09 MF59-adjuvanted influenza vaccine effectiveness. Methods: VE against influenza and/or pneumonia was

  16. 2009 pandemic influenza A (H1N1 virus outbreak and response--Rwanda, October, 2009-May, 2010.

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    Justin Wane

    Full Text Available BACKGROUND: In October 2009, the first case of pandemic influenza A(H1N1pdm09 (pH1N1 was confirmed in Kigali, Rwanda and countrywide dissemination occurred within several weeks. We describe clinical and epidemiological characteristics of this epidemic. METHODS: From October 2009 through May 2010, we undertook epidemiologic investigations and response to pH1N1. Respiratory specimens were collected from all patients meeting the WHO case definition for pH1N1, which were tested using CDC's real time RT-PCR protocol at the Rwandan National Reference Laboratory (NRL. Following documented viral transmission in the community, testing focused on clinically severe and high-risk group suspect cases. RESULTS: From October 9, 2009 through May 31, 2010, NRL tested 2,045 specimens. In total, 26% (n = 532 of specimens tested influenza positive; of these 96% (n = 510 were influenza A and 4% (n = 22 were influenza B. Of cases testing influenza A positive, 96.8% (n = 494, 3% (n = 15, and 0.2% (n = 1 were A(H1N1pdm09, Seasonal A(H3 and Seasonal A(non-subtyped, respectively. Among laboratory-confirmed cases, 263 (53.2% were children <15 years and 275 (52% were female. In total, 58 (12% cases were hospitalized with mean duration of hospitalization of 5 days (Range: 2-15 days. All cases recovered and there were no deaths. Overall, 339 (68% confirmed cases received oseltamivir in any setting. Among all positive cases, 26.9% (143/532 were among groups known to be at high risk of influenza-associated complications, including age <5 years 23% (122/532, asthma 0.8% (4/532, cardiac disease 1.5% (8/532, pregnancy 0.6% (3/532, diabetes mellitus 0.4% (2/532, and chronic malnutrition 0.8% (4/532. CONCLUSIONS: Rwanda experienced a PH1N1 outbreak which was epidemiologically similar to PH1N1 outbreaks in the region. Unlike seasonal influenza, children <15 years were the most affected by pH1N1. Lessons learned from the outbreak response included the need to

  17. Genetic Characterization of Continually Evolving Highly Pathogenic H5N6 Influenza Viruses in China, 2012–2016

    Science.gov (United States)

    Li, Meng; Zhao, Na; Luo, Jing; Li, Yuan; Chen, Lin; Ma, Jiajun; Zhao, Lin; Yuan, Guohui; Wang, Chengmin; Wang, Yutian; Liu, Yanhua; He, Hongxuan

    2017-01-01

    H5N6 is a highly pathogenic avian influenza (HPAI) and a zoonotic disease that causes recurring endemics in East Asia. At least 155 H5N6 outbreaks, including 15 human infections, have been reported in China. These repeated outbreaks have increased concern that the H5N6 virus may cross over to humans and cause a pandemic. In February, 2016, peafowls in a breeding farm exhibited a highly contagious disease. Post-mortem examinations, including RT-PCR, and virus isolation, confirmed that the highly pathogenic H5N6 influenza virus was the causative agent, and the strain was named A/Pavo Cristatus/Jiangxi/JA1/2016. In animal experiments, it exhibited high pathogenicity in chickens and an estimated median lethal dose in mice of ~104.3 TCID50. A phylogenetic analysis showed that JA1/2016 was clustered in H5 clade 2.3.4.4. FG594-like H5N6 virus from Guangdong Province was the probable predecessor of JA1/2016, and the estimated divergence time was June 2014. Furthermore, we found that H5N6 influenza viruses can be classified into the two following groups: Group 1 and Group 2. Group 2 influenza viruses have not been detected since the end of 2014, whereas Group 1 influenza viruses have continually evolved and reassorted with the “gene pool” circulating in south China, resulting in the rise of novel subtypes of this influenza virus. An increase in the number of its identified hosts, the expanding range of its distribution, and the continual evolution of H5N6 AIVs enhance the risk that an H5N6 virus may spread to other continents and cause a pandemic. PMID:28293218

  18. Influence of Novel Highly Pathogenic Avian Influenza A (H5N1 Virus Infection on Migrating Whooper Swans Fecal Microbiota

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    Na Zhao

    2018-02-01

    Full Text Available The migration of wild birds plays an important role in the transmission and spread of H5 highly pathogenic avian influenza (HPAI virus, posing a severe risk to animal and human health. Substantial evidence suggests that altered gut microbial community is implicated in the infection of respiratory influenza virus. However, the influence of H5N1 infection in gut microbiota of migratory birds remains unknown. In January 2015, a novel recombinant H5N1 virus emerged and killed about 100 migratory birds, mainly including whooper swans in Sanmenxia Reservoir Area of China. Here, we describe the first fecal microbiome diversity study of H5N1-infected migratory birds. By investigating the influence of H5N1 infection on fecal bacterial communities in infected and uninfected individuals, we found that H5N1 infection shaped the gut microbiota composition by a difference in the dominance of some genera, such as Aeromonas and Lactobacillus. We also found a decreased α diversity and increased β diversity in infectious individuals. Our results highlight that increases in changes in pathogen-containing gut communities occur when individuals become infected with H5N1. Our study may provide the first evidence that there are statistical association among H5N1 presence and fecal microbiota compositional shifts, and properties of the fecal microbiota may serve as the risk of gut-linked disease in migrates with H5N1 and further aggravate the disease transmission.

  19. Influence of Novel Highly Pathogenic Avian Influenza A (H5N1) Virus Infection on Migrating Whooper Swans Fecal Microbiota.

    Science.gov (United States)

    Zhao, Na; Wang, Supen; Li, Hongyi; Liu, Shelan; Li, Meng; Luo, Jing; Su, Wen; He, Hongxuan

    2018-01-01

    The migration of wild birds plays an important role in the transmission and spread of H5 highly pathogenic avian influenza (HPAI) virus, posing a severe risk to animal and human health. Substantial evidence suggests that altered gut microbial community is implicated in the infection of respiratory influenza virus. However, the influence of H5N1 infection in gut microbiota of migratory birds remains unknown. In January 2015, a novel recombinant H5N1 virus emerged and killed about 100 migratory birds, mainly including whooper swans in Sanmenxia Reservoir Area of China. Here, we describe the first fecal microbiome diversity study of H5N1-infected migratory birds. By investigating the influence of H5N1 infection on fecal bacterial communities in infected and uninfected individuals, we found that H5N1 infection shaped the gut microbiota composition by a difference in the dominance of some genera, such as Aeromonas and Lactobacillus . We also found a decreased α diversity and increased β diversity in infectious individuals. Our results highlight that increases in changes in pathogen-containing gut communities occur when individuals become infected with H5N1. Our study may provide the first evidence that there are statistical association among H5N1 presence and fecal microbiota compositional shifts, and properties of the fecal microbiota may serve as the risk of gut-linked disease in migrates with H5N1 and further aggravate the disease transmission.

  20. Pandemic vaccination strategies and influenza severe outcomes during the influenza A(H1N1)pdm09 pandemic and the post-pandemic influenza season

    DEFF Research Database (Denmark)

    Gil Cuesta, Julita; Aavitsland, Preben; Englund, Hélène

    2016-01-01

    During the 2009/10 influenza A(H1N1)pdm09 pandemic, the five Nordic countries adopted different approaches to pandemic vaccination. We compared pandemic vaccination strategies and severe influenza outcomes, in seasons 2009/10 and 2010/11 in these countries with similar influenza surveillance...... systems. We calculated the cumulative pandemic vaccination coverage in 2009/10 and cumulative incidence rates of laboratory confirmed A(H1N1)pdm09 infections, intensive care unit (ICU) admissions and deaths in 2009/10 and 2010/11. We estimated incidence risk ratios (IRR) in a Poisson regression model...... with the other countries. In 2010/11 Denmark had a significantly higher cumulative incidence of A(H1N1)pdm09 ICU admissions (IRR: 2.4; 95% confidence interval (CI): 1.9-3.0) and deaths (IRR: 8.3; 95% CI: 5.1-13.5). Compared with Denmark, the other countries had higher pandemic vaccination coverage...

  1. Antigenic variation of H1N1, H1N2 and H3N2 swine influenza viruses in Japan and Vietnam.

    Science.gov (United States)

    Takemae, Nobuhiro; Nguyen, Tung; Ngo, Long Thanh; Hiromoto, Yasuaki; Uchida, Yuko; Pham, Vu Phong; Kageyama, Tsutomu; Kasuo, Shizuko; Shimada, Shinichi; Yamashita, Yasutaka; Goto, Kaoru; Kubo, Hideyuki; Le, Vu Tri; Van Vo, Hung; Do, Hoa Thi; Nguyen, Dang Hoang; Hayashi, Tsuyoshi; Matsuu, Aya; Saito, Takehiko

    2013-04-01

    The antigenicity of the influenza A virus hemagglutinin is responsible for vaccine efficacy in protecting pigs against swine influenza virus (SIV) infection. However, the antigenicity of SIV strains currently circulating in Japan and Vietnam has not been well characterized. We examined the antigenicity of classical H1 SIVs, pandemic A(H1N1)2009 (A(H1N1)pdm09) viruses, and seasonal human-lineage SIVs isolated in Japan and Vietnam. A hemagglutination inhibition (HI) assay was used to determine antigenic differences that differentiate the recent Japanese H1N2 and H3N2 SIVs from the H1N1 and H3N2 domestic vaccine strains. Minor antigenic variation between pig A(H1N1)pdm09 viruses was evident by HI assay using 13 mAbs raised against homologous virus. A Vietnamese H1N2 SIV, whose H1 gene originated from a human strain in the mid-2000s, reacted poorly with post-infection ferret serum against human vaccine strains from 2000-2010. These results provide useful information for selection of optimal strains for SIV vaccine production.

  2. Pandemic influenza A (H1N1)

    African Journals Online (AJOL)

    ... in Port Shepstone, South Africa. Introduction. Influenza A (H1N1) 2009 'swine flu' variant is currently a global pandemic.1 The infection associated with this virus is usually a mild, self-limiting illness. However, it may progress to severe pneumonia requiring intensive care unit (ICU) therapy in 31% of patients.2 This may.

  3. Molecular Evolution and Emergence of H5N6 Avian Influenza Virus in Central China.

    Science.gov (United States)

    Du, Yingying; Chen, Mingyue; Yang, Jiayun; Jia, Yane; Han, Shufang; Holmes, Edward C; Cui, Jie

    2017-06-15

    H5N6 avian influenza virus (AIV) has posed a potential threat to public health since its emergence in China in 2013. To understand the evolution and emergence of H5N6 AIV in the avian population, we performed molecular surveillance of live poultry markets (LPMs) in Wugang Prefecture, Hunan Province, in central China, during 2014 and 2015. Wugang Prefecture is located on the Eastern Asian-Australian migratory bird flyway, and a human death due to an H5N6 virus was reported in the prefecture on 21 November 2016. In total, we sampled and sequenced the complete genomes of 175 H5N6 AIVs. Notably, our analysis revealed that H5N6 AIVs contain at least six genotypes arising from segment reassortment, including a rare variant that possesses an HA gene derived from H5N1 clade 2.3.2 and a novel NP gene that has its origins with H7N3 viruses. In addition, phylogenetic analysis revealed that genetically similar H5N6 AIVs tend to cluster according to their geographic regions of origin. These results help to reveal the evolutionary behavior of influenza viruses prior to their emergence in humans. IMPORTANCE The newly emerged H5N6 influenza A virus has caused more than 10 human deaths in China since 2013. In November 2016, a human death due to an H5N6 virus, in Wugang Prefecture, Hunan Province, was confirmed by the WHO. To better understand the evolution and emergence of H5N6 viruses, we surveyed live poultry markets (LPMs) in Wugang Prefecture before the reported human death, with a focus on revealing the diversity and genomic origins of H5N6 in birds during 2014 and 2015. In general, H5N6 viruses in this region were most closely related to H5N1 clade 2.3.4.4, with the exception of one virus with an HA gene derived from clade 2.3.2 such that it represents a novel reassortant. Clearly, the ongoing surveillance of LPMs is central to monitoring the emergence of pathogenic influenza viruses. Copyright © 2017 American Society for Microbiology.

  4. Antigenic Variation in H5N1 clade 2.1 Viruses in Indonesia from 2005 to 2011

    Directory of Open Access Journals (Sweden)

    Vivi Setiawaty

    2013-01-01

    Full Text Available Influenza A (H5N1 virus, has spread to several countries in the world and has a high mortality rate. Meanwhile, the virus has evolved into several clades. The human influenza A (H5N1 virus circulating in Indonesia is a member of clade 2.1, which is different in antigenicity from other clades of influenza A (H5N1. An analysis of the antigenic variation in the H5 hemagglutinin gene (HA of the influenza A (H5N1 virus strains circulating in Indonesia has been undertaken. Several position of amino acid mutations, including mutations at positions 35, 53, 141, 145, 163, 174, 183, 184, 189, and 231, have been identified. The mutation Val-174-Iso appears to play an important role in immunogenicity and cross-reactivity with rabbit antisera. This study shows that the evolution of the H5HA antigenic variation of the influenza A (H5N1 virus circulating in Indonesia from 2005 to 2011 may affect the immunogenicity of the virus.

  5. In Silico Identification of Highly Conserved Epitopes of Influenza A H1N1, H2N2, H3N2, and H5N1 with Diagnostic and Vaccination Potential

    Directory of Open Access Journals (Sweden)

    José Esteban Muñoz-Medina

    2015-01-01

    Full Text Available The unpredictable, evolutionary nature of the influenza A virus (IAV is the primary problem when generating a vaccine and when designing diagnostic strategies; thus, it is necessary to determine the constant regions in viral proteins. In this study, we completed an in silico analysis of the reported epitopes of the 4 IAV proteins that are antigenically most significant (HA, NA, NP, and M2 in the 3 strains with the greatest world circulation in the last century (H1N1, H2N2, and H3N2 and in one of the main aviary subtypes responsible for zoonosis (H5N1. For this purpose, the HMMER program was used to align 3,016 epitopes reported in the Immune Epitope Database and Analysis Resource (IEDB and distributed in 34,294 stored sequences in the Pfam database. Eighteen epitopes were identified: 8 in HA, 5 in NA, 3 in NP, and 2 in M2. These epitopes have remained constant since they were first identified (~91 years and are present in strains that have circulated on 5 continents. These sites could be targets for vaccination design strategies based on epitopes and/or as markers in the implementation of diagnostic techniques.

  6. Centralized Consensus Hemagglutinin Genes Induce Protective Immunity against H1, H3 and H5 Influenza Viruses.

    Directory of Open Access Journals (Sweden)

    Richard J Webby

    Full Text Available With the exception of the live attenuated influenza vaccine there have been no substantial changes in influenza vaccine strategies since the 1940's. Here we report an alternative vaccine approach that uses Adenovirus-vectored centralized hemagglutinin (HA genes as vaccine antigens. Consensus H1-Con, H3-Con and H5-Con HA genes were computationally derived. Mice were immunized with Ad vaccines expressing the centralized genes individually. Groups of mice were vaccinated with 1 X 1010, 5 X 107 and 1 X 107 virus particles per mouse to represent high, intermediate and low doses, respectively. 100% of the mice that were vaccinated with the high dose vaccine were protected from heterologous lethal challenges within each subtype. In addition to 100% survival, there were no signs of weight loss and disease in 7 out of 8 groups of high dose vaccinated mice. Lower doses of vaccine showed a reduction of protection in a dose-dependent manner. However, even the lowest dose of vaccine provided significant levels of protection against the divergent influenza strains, especially considering the stringency of the challenge virus. In addition, we found that all doses of H5-Con vaccine were capable of providing complete protection against mortality when challenged with lethal doses of all 3 H5N1 influenza strains. This data demonstrates that centralized H1-Con, H3-Con and H5-Con genes can be effectively used to completely protect mice against many diverse strains of influenza. Therefore, we believe that these Ad-vectored centralized genes could be easily translated into new human vaccines.

  7. In vitro assessment of attachment pattern and replication efficiency of H5N1 influenza A viruses with altered receptor specificity.

    Science.gov (United States)

    Chutinimitkul, Salin; van Riel, Debby; Munster, Vincent J; van den Brand, Judith M A; Rimmelzwaan, Guus F; Kuiken, Thijs; Osterhaus, Albert D M E; Fouchier, Ron A M; de Wit, Emmie

    2010-07-01

    The continuous circulation of the highly pathogenic avian influenza (HPAI) H5N1 virus has been a cause of great concern. The possibility of this virus acquiring specificity for the human influenza A virus receptor, alpha2,6-linked sialic acids (SA), and being able to transmit efficiently among humans is a constant threat to human health. Different studies have described amino acid substitutions in hemagglutinin (HA) of clinical HPAI H5N1 isolates or that were introduced experimentally that resulted in an increased, but not exclusive, binding of these virus strains to alpha2,6-linked SA. We introduced all previously described amino acid substitutions and combinations thereof into a single genetic background, influenza virus A/Indonesia/5/05 HA, and tested the receptor specificity of these 27 mutant viruses. The attachment pattern to ferret and human tissues of the upper and lower respiratory tract of viruses with alpha2,6-linked SA receptor preference was then determined and compared to the attachment pattern of a human influenza A virus (H3N2). At least three mutant viruses showed an attachment pattern to the human respiratory tract similar to that of the human H3N2 virus. Next, the replication efficiencies of these mutant viruses and the effects of three different neuraminidases on virus replication were determined. These data show that influenza virus A/Indonesia/5/05 potentially requires only a single amino acid substitution to acquire human receptor specificity, while at the same time remaining replication competent, thus suggesting that the pandemic threat posed by HPAI H5N1 is far from diminished.

  8. In Vitro Assessment of Attachment Pattern and Replication Efficiency of H5N1 Influenza A Viruses with Altered Receptor Specificity▿

    Science.gov (United States)

    Chutinimitkul, Salin; van Riel, Debby; Munster, Vincent J.; van den Brand, Judith M. A.; Rimmelzwaan, Guus F.; Kuiken, Thijs; Osterhaus, Albert D. M. E.; Fouchier, Ron A. M.; de Wit, Emmie

    2010-01-01

    The continuous circulation of the highly pathogenic avian influenza (HPAI) H5N1 virus has been a cause of great concern. The possibility of this virus acquiring specificity for the human influenza A virus receptor, α2,6-linked sialic acids (SA), and being able to transmit efficiently among humans is a constant threat to human health. Different studies have described amino acid substitutions in hemagglutinin (HA) of clinical HPAI H5N1 isolates or that were introduced experimentally that resulted in an increased, but not exclusive, binding of these virus strains to α2,6-linked SA. We introduced all previously described amino acid substitutions and combinations thereof into a single genetic background, influenza virus A/Indonesia/5/05 HA, and tested the receptor specificity of these 27 mutant viruses. The attachment pattern to ferret and human tissues of the upper and lower respiratory tract of viruses with α2,6-linked SA receptor preference was then determined and compared to the attachment pattern of a human influenza A virus (H3N2). At least three mutant viruses showed an attachment pattern to the human respiratory tract similar to that of the human H3N2 virus. Next, the replication efficiencies of these mutant viruses and the effects of three different neuraminidases on virus replication were determined. These data show that influenza virus A/Indonesia/5/05 potentially requires only a single amino acid substitution to acquire human receptor specificity, while at the same time remaining replication competent, thus suggesting that the pandemic threat posed by HPAI H5N1 is far from diminished. PMID:20392847

  9. High-yield production of a stable Vero cell-based vaccine candidate against the highly pathogenic avian influenza virus H5N1

    International Nuclear Information System (INIS)

    Zhou, Fangye; Zhou, Jian; Ma, Lei; Song, Shaohui; Zhang, Xinwen; Li, Weidong; Jiang, Shude; Wang, Yue; Liao, Guoyang

    2012-01-01

    Highlights: ► Vero cell-based HPAI H5N1 vaccine with stable high yield. ► Stable high yield derived from the YNVa H3N2 backbone. ► H5N1/YNVa has a similar safety and immunogenicity to H5N1delta. -- Abstract: Highly pathogenic avian influenza (HPAI) viruses pose a global pandemic threat, for which rapid large-scale vaccine production technology is critical for prevention and control. Because chickens are highly susceptible to HPAI viruses, the supply of chicken embryos for vaccine production might be depleted during a virus outbreak. Therefore, developing HPAI virus vaccines using other technologies is critical. Meeting vaccine demand using the Vero cell-based fermentation process has been hindered by low stability and yield. In this study, a Vero cell-based HPAI H5N1 vaccine candidate (H5N1/YNVa) with stable high yield was achieved by reassortment of the Vero-adapted (Va) high growth A/Yunnan/1/2005(H3N2) (YNVa) virus with the A/Anhui/1/2005(H5N1) attenuated influenza vaccine strain (H5N1delta) using the 6/2 method. The reassorted H5N1/YNVa vaccine maintained a high hemagglutination (HA) titer of 1024. Furthermore, H5N1/YNVa displayed low pathogenicity and uniform immunogenicity compared to that of the parent virus.

  10. Novel pandemic influenza A(H1N1 viruses are potently inhibited by DAS181, a sialidase fusion protein.

    Directory of Open Access Journals (Sweden)

    Gallen B Triana-Baltzer

    2009-11-01

    Full Text Available The recent emergence of a novel pandemic influenza A(H1N1 strain in humans exemplifies the rapid and unpredictable nature of influenza virus evolution and the need for effective therapeutics and vaccines to control such outbreaks. However, resistance to antivirals can be a formidable problem as evidenced by the currently widespread oseltamivir- and adamantane-resistant seasonal influenza A viruses (IFV. Additional antiviral approaches with novel mechanisms of action are needed to combat novel and resistant influenza strains. DAS181 (Fludase is a sialidase fusion protein in early clinical development with in vitro and in vivo preclinical activity against a variety of seasonal influenza strains and highly pathogenic avian influenza strains (A/H5N1. Here, we use in vitro, ex vivo, and in vivo models to evaluate the activity of DAS181 against several pandemic influenza A(H1N1 viruses.The activity of DAS181 against several pandemic influenza A(H1N1 virus isolates was examined in MDCK cells, differentiated primary human respiratory tract culture, ex-vivo human bronchi tissue and mice. DAS181 efficiently inhibited viral replication in each of these models and against all tested pandemic influenza A(H1N1 strains. DAS181 treatment also protected mice from pandemic influenza A(H1N1-induced pathogenesis. Furthermore, DAS181 antiviral activity against pandemic influenza A(H1N1 strains was comparable to that observed against seasonal influenza virus including the H274Y oseltamivir-resistant influenza virus.The sialidase fusion protein DAS181 exhibits potent inhibitory activity against pandemic influenza A(H1N1 viruses. As inhibition was also observed with oseltamivir-resistant IFV (H274Y, DAS181 may be active against the antigenically novel pandemic influenza A(H1N1 virus should it acquire the H274Y mutation. Based on these and previous results demonstrating DAS181 broad-spectrum anti-IFV activity, DAS181 represents a potential therapeutic agent for

  11. Cytokine response patterns in severe pandemic 2009 H1N1 and seasonal influenza among hospitalized adults.

    Directory of Open Access Journals (Sweden)

    Nelson Lee

    Full Text Available BACKGROUND: Studying cytokine/chemokine responses in severe influenza infections caused by different virus subtypes may improve understanding on pathogenesis. METHODS: Adults hospitalized for laboratory-confirmed seasonal and pandemic 2009 A/H1N1 (pH1N1 influenza were studied. Plasma concentrations of 13 cytokines/chemokines were measured at presentation and then serially, using cytometric-bead-array with flow-cytometry and ELISA. PBMCs from influenza patients were studied for cytokine/chemokine expression using ex-vivo culture (Whole Blood Assay,±PHA/LPS stimulation. Clinical variables were prospectively recorded and analyzed. RESULTS: 63 pH1N1 and 53 seasonal influenza patients were studied. pH1N1 patients were younger (mean±S.D. 42.8±19.2 vs 70.5±16.7 years, and fewer had comorbidities. Respiratory/cardiovascular complications were common in both groups (71.4% vs 81.1%, although severe pneumonia with hypoxemia (54.0% vs 28.3% and ICU admissions (25.4% vs 1.9% were more frequent with pH1N1. Hyperactivation of the proinflammatory cytokines IL-6, CXCL8/IL-8, CCL2/MCP-1 and sTNFR-1 was found in pH1N1 pneumonia (2-15 times normal and in complicated seasonal influenza, but not in milder pH1N1 infections. The adaptive-immunity (Th1/Th17-related CXCL10/IP-10, CXCL9/MIG and IL-17A however, were markedly suppressed in severe pH1N1 pneumonia (2-27 times lower than seasonal influenza; P-values<0.01. This pattern was further confirmed with serial measurements. Hypercytokinemia tended to be sustained in pH1N1 pneumonia, associated with a slower viral clearance [PCR-negativity: day 3-4, 55% vs 85%; day 6-7, 67% vs 100%]. Elevated proinflammatory cytokines, particularly IL-6, predicted ICU admission (adjusted OR 12.6, 95%CI 2.6-61.5, per log(10unit increase; P = 0.002, and correlated with fever, tachypnoea, deoxygenation, and length-of-stay (Spearman's rho, P-values<0.01 in influenza infections. PBMCs in seasonal influenza patients were activated and

  12. Genome characterisation of the newly discovered avian influenza A H5N7 virus subtype combination

    DEFF Research Database (Denmark)

    Bragstad, K.; Jørgensen, Poul Henrik; Handberg, K.J.

    2007-01-01

    In Denmark, in 2003, a previously unknown subtype combination of avian influenza A virus, H5N7 (A/Mallard/Denmark/64650/03), was isolated from a flock of 12,000 mallards. The H5N7 subtype combination might be a reassortant between recent European avian influenza A H5, H7, and a third subtype......) and the human-fatal A/Netherlands/219/03 (H7N7), respectively. The basic polymerase 1 and 2 genes were phylogenetically equidistant to both A/Duck/Denmark/65047/04 (H5N2) and A/Chicken/Netherlands/1/03 (H7N7). The nucleoprotein and matrix gene had highest nucleotide sequence similarity to the H6 subtypes A....../Duck/Hong Kong/3096/99 (H6N2) and A/WDk/ST/1737/2000 (H6N8), respectively. All genes of the H5N7 strain were of avian origin, and no further evidence of pathogenicity to humans has been found....

  13. [Analysis of risk factors of fatal outcome in pregnant and puerperant patients with severe H1N1 influenza].

    Science.gov (United States)

    Zabolotskikh, I B; Penzhoian, G A; Musaeva, T S; Goncharenko, S I

    2010-01-01

    As well as previous epidemics and pandemias of influenza, the 2009 H1N1 influenza pandemia increases the risk of severe illness in pregnant. Data were reported for 28 pregnant and 2 postpartum women who have been hospitalized in ICUs of Krasnodar Region with H1N1 influenza diagnosis. The laboratory tests for H1N1 were negative in 53.3% of suspected cases of H1N1 influenza (16 of 30). The major lethal risk factor in pregnant with H1N1 influenza is a development of septic shock with low PaO2\\FiO2 ratio (less than 140) and high Murray's Acute Lung Injury Score (higher than 2.5). High Apache II, Apache III, SAPS 2, SAPS 3 and SOFA scores are the additional lethal risk factors. Lethal outcomes were more frequent in the end of the second trimester of pregnancy.

  14. Novel Polymerase Gene Mutations for Human Adaptation in Clinical Isolates of Avian H5N1 Influenza Viruses.

    Directory of Open Access Journals (Sweden)

    Yasuha Arai

    2016-04-01

    Full Text Available A major determinant in the change of the avian influenza virus host range to humans is the E627K substitution in the PB2 polymerase protein. However, the polymerase activity of avian influenza viruses with a single PB2-E627K mutation is still lower than that of seasonal human influenza viruses, implying that avian viruses require polymerase mutations in addition to PB2-627K for human adaptation. Here, we used a database search of H5N1 clade 2.2.1 virus sequences with the PB2-627K mutation to identify other polymerase adaptation mutations that have been selected in infected patients. Several of the mutations identified acted cooperatively with PB2-627K to increase viral growth in human airway epithelial cells and mouse lungs. These mutations were in multiple domains of the polymerase complex other than the PB2-627 domain, highlighting a complicated avian-to-human adaptation pathway of avian influenza viruses. Thus, H5N1 viruses could rapidly acquire multiple polymerase mutations that function cooperatively with PB2-627K in infected patients for optimal human adaptation.

  15. Natural co-infection of influenza A/H3N2 and A/H1N1pdm09 viruses resulting in a reassortant A/H3N2 virus.

    Science.gov (United States)

    Rith, Sareth; Chin, Savuth; Sar, Borann; Y, Phalla; Horm, Srey Viseth; Ly, Sovann; Buchy, Philippe; Dussart, Philippe; Horwood, Paul F

    2015-12-01

    Despite annual co-circulation of different subtypes of seasonal influenza, co-infections between different viruses are rarely detected. These co-infections can result in the emergence of reassortant progeny. We document the detection of an influenza co-infection, between influenza A/H3N2 with A/H1N1pdm09 viruses, which occurred in a 3 year old male in Cambodia during April 2014. Both viruses were detected in the patient at relatively high viral loads (as determined by real-time RT-PCR CT values), which is unusual for influenza co-infections. As reassortment can occur between co-infected influenza A strains we isolated plaque purified clonal viral populations from the clinical material of the patient infected with A/H3N2 and A/H1N1pdm09. Complete genome sequences were completed for 7 clonal viruses to determine if any reassorted viruses were generated during the influenza virus co-infection. Although most of the viral sequences were consistent with wild-type A/H3N2 or A/H1N1pdm09, one reassortant A/H3N2 virus was isolated which contained an A/H1N1pdm09 NS1 gene fragment. The reassortant virus was viable and able to infect cells, as judged by successful passage in MDCK cells, achieving a TCID50 of 10(4)/ml at passage number two. There is no evidence that the reassortant virus was transmitted further. The co-infection occurred during a period when co-circulation of A/H3N2 and A/H1N1pdm09 was detected in Cambodia. It is unclear how often influenza co-infections occur, but laboratories should consider influenza co-infections during routine surveillance activities. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  16. Immune protection induced on day 10 following administration of the 2009 A/H1N1 pandemic influenza vaccine.

    Directory of Open Access Journals (Sweden)

    Yizhuo Sun

    Full Text Available BACKGROUND: The 2009 swine-origin influenza virus (S-OIV H1N1 pandemic has caused more than 18,000 deaths worldwide. Vaccines against the 2009 A/H1N1 influenza virus are useful for preventing infection and controlling the pandemic. The kinetics of the immune response following vaccination with the 2009 A/H1N1 influenza vaccine need further investigation. METHODOLOGY/PRINCIPAL FINDINGS: 58 volunteers were vaccinated with a 2009 A/H1N1 pandemic influenza monovalent split-virus vaccine (15 µg, single-dose. The sera were collected before Day 0 (pre-vaccination and on Days 3, 5, 10, 14, 21, 30, 45 and 60 post vaccination. Specific antibody responses induced by the vaccination were analyzed using hemagglutination inhibition (HI assay and enzyme-linked immunosorbent assay (ELISA. After administration of the 2009 A/H1N1 influenza vaccine, specific and protective antibody response with a major subtype of IgG was sufficiently developed as early as Day 10 (seroprotection rate: 93%. This specific antibody response could maintain for at least 60 days without significant reduction. Antibody response induced by the 2009 A/H1N1 influenza vaccine could not render protection against seasonal H1N1 influenza (seroconversion rate: 3% on Day 21. However, volunteers with higher pre-existing seasonal influenza antibody levels (pre-vaccination HI titer ≥1∶40, Group 1 more easily developed a strong antibody protection effect against the 2009 A/H1N1 influenza vaccine as compared with those showing lower pre-existing seasonal influenza antibody levels (pre-vaccination HI titer <1∶40, Group 2. The titer of the specific antibody against the 2009 A/H1N1 influenza was much higher in Group 1 (geometric mean titer: 146 on Day 21 than that in Group 2 (geometric mean titer: 70 on Day 21. CONCLUSIONS/SIGNIFICANCE: Recipients could gain sufficient protection as early as 10 days after vaccine administration. The protection could last at least 60 days. Individuals with a

  17. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

    OpenAIRE

    Ramis , Antonio; van Amerongen , Geert; van de Bildt , Marco; Leijten , Loneke; Vanderstichel , Raphael; Osterhaus , Albert; Kuiken , Thijs

    2014-01-01

    Historically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental HPAIV H5N1 infection of black-headed gulls (Chroicocephalus ridibundus) to determine their susceptibility to infection and disease from this virus, pattern of viral shedding, clinical signs, pathological changes a...

  18. Effect of receptor binding domain mutations on receptor binding and transmissibility of avian influenza H5N1 viruses

    DEFF Research Database (Denmark)

    Maines, Taronna R; Chen, Li-Mei; Van Hoeven, Neal

    2011-01-01

    Although H5N1 influenza viruses have been responsible for hundreds of human infections, these avian influenza viruses have not fully adapted to the human host. The lack of sustained transmission in humans may be due, in part, to their avian-like receptor preference. Here, we have introduced recep...

  19. Influenza A H5N1 clade 2.3.4 virus with a different antiviral susceptibility profile replaced clade 1 virus in humans in northern Vietnam.

    Directory of Open Access Journals (Sweden)

    Mai T Q Le

    2008-10-01

    Full Text Available Prior to 2007, highly pathogenic avian influenza (HPAI H5N1 viruses isolated from poultry and humans in Vietnam were consistently reported to be clade 1 viruses, susceptible to oseltamivir but resistant to amantadine. Here we describe the re-emergence of human HPAI H5N1 virus infections in Vietnam in 2007 and the characteristics of the isolated viruses.Respiratory specimens from patients suspected to be infected with avian influenza in 2007 were screened by influenza and H5 subtype specific polymerase chain reaction. Isolated H5N1 strains were further characterized by genome sequencing and drug susceptibility testing. Eleven poultry outbreak isolates from 2007 were included in the sequence analysis. Eight patients, all of them from northern Vietnam, were diagnosed with H5N1 in 2007 and five of them died. Phylogenetic analysis of H5N1 viruses isolated from humans and poultry in 2007 showed that clade 2.3.4 H5N1 viruses replaced clade 1 viruses in northern Vietnam. Four human H5N1 strains had eight-fold reduced in-vitro susceptibility to oseltamivir as compared to clade 1 viruses. In two poultry isolates the I117V mutation was found in the neuraminidase gene, which is associated with reduced susceptibility to oseltamivir. No mutations in the M2 gene conferring amantadine resistance were found.In 2007, H5N1 clade 2.3.4 viruses replaced clade 1 viruses in northern Vietnam and were susceptible to amantadine but showed reduced susceptibility to oseltamivir. Combination antiviral therapy with oseltamivir and amantadine for human cases in Vietnam is recommended.

  20. Amino Acid Substitutions Associated with Avian H5N6 Influenza A Virus Adaptation to Mice

    Directory of Open Access Journals (Sweden)

    Chunmao Zhang

    2017-09-01

    Full Text Available At least 15 cases of human beings infected with H5N6 have been reported since 2014, of which at least nine were fatal. The highly pathogenic avian H5N6 influenza virus may pose a serious threat to both public health and the poultry industry. However, the molecular features promoting the adaptation of avian H5N6 influenza viruses to mammalian hosts is not well understood. Here, we sequentially passaged an avian H5N6 influenza A virus (A/Northern Shoveler/Ningxia/488-53/2015 10 times in mice to identify the adaptive amino acid substitutions that confer enhanced virulence to H5N6 in mammals. The 1st and 10th passages of the mouse-adapted H5N6 viruses were named P1 and P10, respectively. P1 and P10 displayed higher pathogenicity in mice than their parent strain. P10 showed significantly higher replication capability in vivo and could be detected in the brains of mice, whereas P1 displayed higher replication efficiency in their lungs but was not detectable in the brain. Similar to its parent strain, P10 remained no transmissible between guinea pigs. Using genome sequencing and alignment, multiple amino acid substitutions, including PB2 E627K, PB2 T23I, PA T97I, and HA R239H, were found in the adaptation of H5N6 to mice. In summary, we identified amino acid changes that are associated with H5N6 adaptation to mice.

  1. Isolation and molecular characterization of an H5N1 swine influenza virus in China in 2015.

    Science.gov (United States)

    Wu, Haibo; Yang, Fan; Lu, Rufeng; Xu, Lihua; Liu, Fumin; Peng, Xiuming; Wu, Nanping

    2018-03-01

    In 2015, an H5N1 influenza virus was isolated from a pig in Zhejiang Province, Eastern China. This strain was characterized by whole-genome sequencing with subsequent phylogenetic analysis. Phylogenetic analysis showed that all segments from this strain belonged to clade 2.3.2 and that it had received its genes from poultry influenza viruses in China. A Glu627Lys mutation associated with pathogenicity was observed in the PB2 protein. This strain was moderately pathogenic in mice and was able to replicate without prior adaptation. These results suggest that active surveillance of swine influenza should be used as an early warning system for influenza outbreaks in mammals.

  2. Silent spread of highly pathogenic Avian Influenza H5N1 virus amongst vaccinated commercial layers

    NARCIS (Netherlands)

    Poetri, O.N.; Boven, M.; Claassen, I.J.T.M.; Koch, G.; Wibawan, I.W.; Stegeman, A.; Broek, van den J.; Bouma, A.

    2014-01-01

    The aim of this study was to determine whether a single vaccination of commercial layer type chickens with an inactivated vaccine containing highly pathogenic avian influenza virus strain H5N1 A/chicken/Legok/2003, carried out on the farm, was sufficient to protect against infection with the

  3. High-yield production of a stable Vero cell-based vaccine candidate against the highly pathogenic avian influenza virus H5N1

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Fangye; Zhou, Jian; Ma, Lei; Song, Shaohui; Zhang, Xinwen; Li, Weidong; Jiang, Shude [No. 5, Department of Bioproducts, Institute of Medical Biology, Chinese Academy of Medical Science and Pecking Union Medical College, Jiaoling Avenue 935, Kunming, Yunnan Province 650102, People' s Republic of China (China); Wang, Yue [National Institute for Viral Disease Control and Prevention, China Center for Disease Control and Prevention, Yingxin Lane 100, Xicheng District, Beijing 100052, People' s Republic of China (China); Liao, Guoyang [No. 5, Department of Bioproducts, Institute of Medical Biology, Chinese Academy of Medical Science and Pecking Union Medical College, Jiaoling Avenue 935, Kunming, Yunnan Province 650102, People' s Republic of China (China)

    2012-05-18

    Highlights: Black-Right-Pointing-Pointer Vero cell-based HPAI H5N1 vaccine with stable high yield. Black-Right-Pointing-Pointer Stable high yield derived from the YNVa H3N2 backbone. Black-Right-Pointing-Pointer H5N1/YNVa has a similar safety and immunogenicity to H5N1delta. -- Abstract: Highly pathogenic avian influenza (HPAI) viruses pose a global pandemic threat, for which rapid large-scale vaccine production technology is critical for prevention and control. Because chickens are highly susceptible to HPAI viruses, the supply of chicken embryos for vaccine production might be depleted during a virus outbreak. Therefore, developing HPAI virus vaccines using other technologies is critical. Meeting vaccine demand using the Vero cell-based fermentation process has been hindered by low stability and yield. In this study, a Vero cell-based HPAI H5N1 vaccine candidate (H5N1/YNVa) with stable high yield was achieved by reassortment of the Vero-adapted (Va) high growth A/Yunnan/1/2005(H3N2) (YNVa) virus with the A/Anhui/1/2005(H5N1) attenuated influenza vaccine strain (H5N1delta) using the 6/2 method. The reassorted H5N1/YNVa vaccine maintained a high hemagglutination (HA) titer of 1024. Furthermore, H5N1/YNVa displayed low pathogenicity and uniform immunogenicity compared to that of the parent virus.

  4. Effect of Neuraminidase Inhibitor–Resistant Mutations on Pathogenicity of Clade 2.2 A/Turkey/15/06 (H5N1) Influenza Virus in Ferrets

    OpenAIRE

    Ilyushina, Natalia A.; Seiler, Jon P.; Rehg, Jerold E.; Webster, Robert G.; Govorkova, Elena A.

    2010-01-01

    The acquisition of neuraminidase (NA) inhibitor resistance by H5N1 influenza viruses has serious clinical implications, as this class of drugs can be an essential component of pandemic control measures. The continuous evolution of the highly pathogenic H5N1 influenza viruses results in the emergence of natural NA gene variations whose impact on viral fitness and NA inhibitor susceptibility are poorly defined. We generated seven genetically stable recombinant clade 2.2 A/Turkey/15/06-like (H5N...

  5. Transmission of highly pathogenic avian influenza H5N1 virus in Pekin ducks is significantly reduced by a genetically distant H5N2 vaccine

    NARCIS (Netherlands)

    Goot, van der J.A.; Boven, van M.; Stegeman, A.; Water, van de S.G.P.; Jong, de M.C.M.; Koch, G.

    2008-01-01

    Domestic ducks play an important role in the epidemiology of H5N1 avian influenza. Although it is known that vaccines that have a high homology with the challenge virus are able to prevent infection in ducks, little is yet known about the ability of genetically more distant vaccines in preventing

  6. Evidence of reassortment of pandemic H1N1 influenza virus in swine in Argentina: are we facing the expansion of potential epicenters of influenza emergence?

    Science.gov (United States)

    Pereda, Ariel; Rimondi, Agustina; Cappuccio, Javier; Sanguinetti, Ramon; Angel, Matthew; Ye, Jianqiang; Sutton, Troy; Dibárbora, Marina; Olivera, Valeria; Craig, Maria I.; Quiroga, Maria; Machuca, Mariana; Ferrero, Andrea; Perfumo, Carlos; Perez, Daniel R.

    2011-01-01

    Please cite this paper as: Pereda et al. (2011) Evidence of reassortment of pandemic H1N1 influenza virus in swine in Argentina: are we facing the expansion of potential epicenters of influenza emergence? Influenza and Other Respiratory Viruses 5(6), 409–412. In this report, we describe the occurrence of two novel swine influenza viruses (SIVs) in pigs in Argentina. These viruses are the result of two independent reassortment events between the H1N1 pandemic influenza virus (H1N1pdm) and human‐like SIVs, showing the constant evolution of influenza viruses at the human–swine interface and the potential health risk of H1N1pdm as it appears to be maintained in the swine population. It must be noted that because of the lack of information regarding the circulation of SIVs in South America, we cannot discard the possibility that ancestors of the H1N1pdm or other SIVs have been present in this part of the world. More importantly, these findings suggest an ever‐expanding geographic range of potential epicenters of influenza emergence with public health risks. PMID:21668680

  7. Central nervous system manifestations in pediatric patients with influenza A H1N1 infection during the 2009 pandemic.

    Science.gov (United States)

    Wilking, Ashley N; Elliott, Elizabeth; Garcia, Melissa N; Murray, Kristy O; Munoz, Flor M

    2014-09-01

    A novel H1N1 influenza A virus (A(H1N1)pdm09) particularly affected individuals central nervous system complications associated with pandemic influenza in the pediatric population. Retrospective review of patients with laboratory-confirmed influenza A(H1N1)pdm09 infection and central nervous system manifestations at Texas Children's Hospital between April 2009 and June 2010. Among 365 patients with influenza A(H1N1)pdm09, 32 (8.8%) had central nervous system manifestations at a median age of 4 years. Eight (25.0%) were previously healthy, and 12 (37.5%) had neurological pre-existing conditions. Of the 32 cases of influenza with neurological complications, seizure (n = 17; 53.1%) was the most common central nervous system manifestation, followed by encephalitis (n = 4; 12.5%), meningitis (n = 4; 12.5%), encephalopathy (n = 3; 9.4%), meningismus (n = 3; 9.4%), focal hemorrhagic brain lesions (n = 2; 6.3%), brain infarction (n = 1; 3.1%), and sensorineural hearing loss (n = 1; 3.1%). Two patients demonstrated two or more types of central nervous system complications. One patient had abnormal cerebrospinal fluid with pleocytosis. Almost two thirds of the children with central nervous system manifestations required intensive care unit admission and nearly half required mechanical ventilation. There were no deaths. Patients with pre-existing neurological conditions were at greater risk for central nervous system manifestations during pandemic influenza infection. Patients with central nervous system manifestations were more likely to experience severe illness, characterized by intensive care unit admission and mechanical ventilation, although overall outcomes were good. Influenza prevention in patients with underlying medical conditions, particularly those with neurological conditions, is important. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. Fulminant hemophagocytic lymphohistiocytosis induced by pandemic A (H1N1 influenza: a case report

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    Wacrenier Agnès

    2011-07-01

    Full Text Available Abstract Introduction Hemophagocytic lymphohistiocytosis induced by viral diseases is a well recognized entity. Severe forms of H5N1 influenza are known to be associated with symptoms very similar to a reactive hemophagocytic syndrome. We report a case of fulminant lymphohistiocytosis associated with the pandemic A (H1N1 variant. Case presentation A 42-year-old Caucasian woman developed a syndrome of fatal hemophagocytic lymphohistiocytosis shortly after H1N1 influenza. Initial symptoms of the viral disease were unusual, with acute abdominal involvement. Our patient's course was complicated by diffuse skin rash and ileal ischemia. Our patient died of refractory shock and multi-organ failure. Skin, ileum and colon histology was consistent with an acute apoptosis combined with an increased cellular regeneration. Conclusions Influenza may be complicated by severe forms of hemophagocytic lymphohistiocytosis. To ensure early recognition and treatment, physicians should be aware of the possible induction of the syndrome by the novel H1N1 variant. The rapid occurrence of a multi-organ involvement with evocative biological features of macrophage activation should alert clinicians.

  9. Efficacy of soap and water and alcohol-based hand-rub preparations against live H1N1 influenza virus on the hands of human volunteers.

    Science.gov (United States)

    Grayson, M Lindsay; Melvani, Sharmila; Druce, Julian; Barr, Ian G; Ballard, Susan A; Johnson, Paul D R; Mastorakos, Tasoula; Birch, Christopher

    2009-02-01

    Although pandemic and avian influenza are known to be transmitted via human hands, there are minimal data regarding the effectiveness of routine hand hygiene (HH) protocols against pandemic and avian influenza. Twenty vaccinated, antibody-positive health care workers had their hands contaminated with 1 mL of 10(7) tissue culture infectious dose (TCID)(50)/0.1 mL live human influenza A virus (H1N1; A/New Caledonia/20/99) before undertaking 1 of 5 HH protocols (no HH [control], soap and water hand washing [SW], or use of 1 of 3 alcohol-based hand rubs [61.5% ethanol gel, 70% ethanol plus 0.5% chlorhexidine solution, or 70% isopropanol plus 0.5% chlorhexidine solution]). H1N1 concentrations were assessed before and after each intervention by viral culture and real-time reverse-transcriptase polymerase chain reaction (PCR). The natural viability of H1N1 on hands for >60 min without HH was also assessed. There was an immediate reduction in culture-detectable and PCR-detectable H1N1 after brief cutaneous air drying--14 of 20 health care workers had H1N1 detected by means of culture (mean reduction, 10(3-4) TCID(50)/0.1 mL), whereas 6 of 20 had no viable H1N1 recovered; all 20 health care workers had similar changes in PCR test results. Marked antiviral efficacy was noted for all 4 HH protocols, on the basis of culture results (14 of 14 had no culturable H1N1; (P< .002) and PCR results (P< .001; cycle threshold value range, 33.3-39.4), with SW statistically superior (P< .001) to all 3 alcohol-based hand rubs, although the actual difference was only 1-100 virus copies/microL. There was minimal reduction in H1N1 after 60 min without HH. HH with SW or alcohol-based hand rub is highly effective in reducing influenza A virus on human hands, although SW is the most effective intervention. Appropriate HH may be an important public health initiative to reduce pandemic and avian influenza transmission.

  10. Detección de virus influenza A, B y subtipos A (H1N1 pdm09, A (H3N2 por múltiple RT-PCR en muestras clínicas

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    Pool Marcos

    Full Text Available Objetivos. Estandarizar la técnica de reacción en cadena de la polimerasa en tiempo real (RT-PCR múltiple para la detección de virus influenza A, B y tipificación de subtipos A (H1N1 pdm09, A (H3N2 en muestras clínicas. Materiales y métodos. Se analizaron 300 muestras de hisopado nasofaríngeo. Esta metodología fue estandarizada en dos pasos: la primera reacción detectó el gen de la matriz del virus de influenza A, gen de la nucleoproteína del virus influenza B y el gen GAPDH de las células huésped. La segunda reacción detectó el gen de la hemaglutinina de los subtipos A (H1N1 pandémico (pdm09 y A (H3N2. Resultados. Se identificaron 109 muestras positivas a influenza A y B, de las cuales 72 fueron positivas a influenza A (36 positivas a influenza A (H1N1 pdm09 y 36 positivos a influenza A (H3N2 y 37 muestras positivas a influenza B. 191 fueron negativas a ambos virus mediante RT-PCR en tiempo real multiplex. Se encontró una sensibilidad y especificidad del 100% al analizar los resultados de ambas reacciones. El límite de detección viral fue del rango de 7 a 9 copias/µL por virus. Los resultados no mostraron ninguna reacción cruzada con otros virus tales como adenovirus, virus sincitial respiratorio, parainfluenza (1,2 y 3, metapneumovirus, subtipos A (H1N1 estacional, A (H5N2 y VIH. Conclusiones. La RT-PCR múltiple demostró ser una prueba muy sensible y específica para la detección de virus influenza A, B y subtipos A (H1N1, H3N2 y su uso puede ser conveniente en brotes estacionales.

  11. Respon Imun Itik Bali terhadap Berbagai Dosis Vaksin Avian Influenza H5N1

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    Ida Bagus Kade Suardana

    2009-09-01

    Full Text Available A study was carried out to investigate the immune response of Bali ducks against various doses ofAvian Influenza H5N1 vaccine. The study was carried out using a complete Random-Split in Time researchdesign as many as 40 of Bali ducks of 3 months age were kept separately in 4 groups. The ducks werevaccinated twice in two week interval with AI H5N1 vaccine of 0 (as negative control, 1/2, 1, and 2 doses.Sera were collected one day before first vaccination, then every week until three weeks after the secondvaccination. All sera were tested by hemaglutination inhibition (HI test. The result shows that antibodylevel with double dose was significantly higher than single dose, half dose, and negative control (P<0.01.However antibody level in ducks vaccinated with single and half dose did not show any significant difference(P > 0.05.

  12. Transmission of Avian Influenza Virus (H3N2) to Dogs

    OpenAIRE

    Song, Daesub; Kang, Bokyu; Lee, Chulseung; Jung, Kwonil; Ha, Gunwoo; Kang, Dongseok; Park, Seongjun; Park, Bongkyun; Oh, Jinsik

    2008-01-01

    In South Korea, where avian influenza virus subtypes H3N2, H5N1, H6N1, and H9N2 circulate or have been detected, 3 genetically similar canine influenza virus (H3N2) strains of avian origin (A/canine/Korea/01/2007, A/canine/Korea/02/2007, and A/canine/Korea/03/2007) were isolated from dogs exhibiting severe respiratory disease. To determine whether the novel canine influenza virus of avian origin was transmitted among dogs, we experimentally infected beagles with this influenza virus (H3N2) is...

  13. Pandemic A/H1N1v influenza 2009 in hospitalized children: a multicenter Belgian survey

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    Blumental Sophie

    2011-11-01

    Full Text Available Abstract Background During the 2009 influenza A/H1N1v pandemic, children were identified as a specific "at risk" group. We conducted a multicentric study to describe pattern of influenza A/H1N1v infection among hospitalized children in Brussels, Belgium. Methods From July 1, 2009, to January 31, 2010, we collected epidemiological and clinical data of all proven (positive H1N1v PCR and probable (positive influenza A antigen or culture pediatric cases of influenza A/H1N1v infections, hospitalized in four tertiary centers. Results During the epidemic period, an excess of 18% of pediatric outpatients and emergency department visits was registered. 215 children were hospitalized with proven/probable influenza A/H1N1v infection. Median age was 31 months. 47% had ≥ 1 comorbid conditions. Febrile respiratory illness was the most common presentation. 36% presented with initial gastrointestinal symptoms and 10% with neurological manifestations. 34% had pneumonia. Only 24% of the patients received oseltamivir but 57% received antibiotics. 10% of children were admitted to PICU, seven of whom with ARDS. Case fatality-rate was 5/215 (2%, concerning only children suffering from chronic neurological disorders. Children over 2 years of age showed a higher propensity to be admitted to PICU (16% vs 1%, p = 0.002 and a higher mortality rate (4% vs 0%, p = 0.06. Infants less than 3 months old showed a milder course of infection, with few respiratory and neurological complications. Conclusion Although influenza A/H1N1v infections were generally self-limited, pediatric burden of disease was significant. Compared to other countries experiencing different health care systems, our Belgian cohort was younger and received less frequently antiviral therapy; disease course and mortality were however similar.

  14. Establishing a laboratory network of influenza diagnosis in Indonesia: an experience from the avian flu (H5N1 outbreak

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    Setiawaty V

    2012-08-01

    Full Text Available Vivi Setiawaty, Krisna NA Pangesti, Ondri D SampurnoNational Institute of Health Research and Development, Ministry of Health, the Republic of Indonesia, Jakarta, IndonesiaAbstract: Indonesia has been part of the global influenza surveillance since the establishment of a National Influenza Center (NIC at the National Institute of Health Research and Development (NIHRD by the Indonesian Ministry of Health in 1975. When the outbreak of avian influenza A (H5N1 occurred, the NIC and US Naval Medical Research Unit 2 were the only diagnostic laboratories equipped for etiology confirmation. The large geographical area of the Republic of Indonesia poses a real challenge to provide prompt and accurate diagnosis nationally. This was the main reason to establish a laboratory network for H5N1 diagnosis in Indonesia. Currently, 44 laboratories have been included in the network capable of performing polymerase chain reaction testing for influenza A. Diagnostic equipment and standard procedures of biosafety and biosecurity of handling specimens have been adopted largely from World Health Organization recommendations.Keywords: influenza, laboratory, networking

  15. Household transmission of 2009 H1N1 influenza virus in Yazd, Iran

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    F. Behnaz

    2012-08-01

    Full Text Available Summary: Objectives: The 2009 pandemic influenza A (H1N1 virus is a public health challenge. Notably, laboratory-confirmed cases do not represent the age group most susceptible to infection. To characterize the age distribution of all cases of H1N1 influenza, we studied the personal contacts of confirmed cases to identify the age group at the highest risk. Methods: We investigated the family members of 162 laboratory-confirmed cases of 2009 H1N1 in Yazd, Iran. Family members were retrospectively asked whether they had ≥2 respiratory symptoms within 7 days of the last contact with the associated index cases. The ages and symptoms of the patients as well as the interval between diagnosis and the onset of symptoms among household contacts were determined using a questionnaire. Results: We identified 596 family members of index cases, 83 (13.9% of whom developed acute respiratory illness. No acute respiratory illness was found in 104 families (64%; however, there were 2 cases in 15 families (9.3% and ≥3 cases in 4 families (24%. Household contacts from 5 to 18 years old were more susceptible to acute respiratory illness than those who were ≥51 years old (RR = 3.174, 95% CI 1.313–7.675 P-value = 0.01. Conclusion: Individuals ≤18 years old were most susceptible to infection by the H1N1 virus. Therefore, in low-income populations, prevention of the spread of H1N1 to this age group should be emphasized. Keywords: Household transmission, 2009 Influenza A (H1N1 virus

  16. Thoracic computerized tomographic (CT findings in 2009 influenza A (H1N1 virus infection in Isfahan, Iran

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    Mojtaba Rostami

    2011-01-01

    Full Text Available Background: Pandemic 2009 H1N1 influenza A virus arrived at Isfahan in August 2009. The virus is still circulating in the world. The abnormal thoracic computerized tomographic (CT scan findings vary widely among the studies of 2009 H1N1 influenza. We evaluated the thoracic CT findings in patients with 2009 H1N1 virus infection to describe findings compared to previously reported findings, and to suggest patterns that may be suggestive for 2009 influenza A (H1N1 in an appropriate clinical setting. Methods: Retrospectively, the archive of all patients with a diagnosis of 2009 H1N1 influenza A were reviewed, in Al-Zahra Hospital in Isfahan, central Iran, between September 23 rd 2009 to February 20 th 2010. Out of 216 patients with confirmed 2009 influenza A (H1N1 virus, 26 cases with abnormal CT were enrolled in the study. Radiologic findings were characterized by the type and pattern of opacities and zonal distribution. Results: Patchy infiltration (34.6%, lobar consolidation (30.8%, and interstitial infiltration (26.9% with airbronchogram (38.5% were the predominant findings in our patients. Bilateral distribution was seen in 80.8% of the patients. Only one patient (3.8% showed ground-glass opacity, predominant radiographic finding in the previous reports and severe acute respiratory syndrome (SARS. Conclusions: The most common thoracic CT findings in pandemic H1N1 were patchy infiltration, lobar consolidation, and interstitial infiltration with airbronchogram and bilateral distribution. While these findings can be associated with other infections; they may be suggestive to 2009 influenza A (H1N1 in the appropriate clinical setting. Various radiographic patterns can be seen in thoracic CT scans of the influenza patients. Imaging findings are nonspecific.

  17. Pulmonary immunization of chickens using non-adjuvanted spray-freeze dried whole inactivated virus vaccine completely protects against highly pathogenic H5N1 avian influenza virus

    NARCIS (Netherlands)

    Peeters, Ben; Tonnis, Wouter F.; Murugappan, Senthil; Rottier, Peter; Koch, Guus; Frijlink, Henderik W.; Huckriede, Anke; Hinrichs, Wouter L. J.

    2014-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 virus is a major threat to public health as well as to the global poultry industry. Most fatal human infections are caused by contact with infected poultry. Therefore, preventing the virus from entering the poultry population is a priority. This is,

  18. In vitro reassortment between endemic H1N2 and 2009 H1N1 pandemic swine influenza viruses generates attenuated viruses.

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    Ben M Hause

    Full Text Available The pandemic H1N1 (pH1N1 influenza virus was first reported in humans in the spring of 2009 and soon thereafter was identified in numerous species, including swine. Reassortant viruses, presumably arising from the co-infection of pH1N1 and endemic swine influenza virus (SIV, were subsequently identified from diagnostic samples collected from swine. In this study, co-infection of swine testicle (ST cells with swine-derived endemic H1N2 (MN745 and pH1N1 (MN432 yielded two reassortant H1N2 viruses (R1 and R2, both possessing a matrix gene derived from pH1N1. In ST cells, the reassortant viruses had growth kinetics similar to the parental H1N2 virus and reached titers approximately 2 log(10 TCID(50/mL higher than the pH1N1 virus, while in A549 cells these viruses had similar growth kinetics. Intranasal challenge of pigs with H1N2, pH1N1, R1 or R2 found that all viruses were capable of infecting and transmitting between direct contact pigs as measured by real time reverse transcription PCR of nasal swabs. Lung samples were also PCR-positive for all challenge groups and influenza-associated microscopic lesions were detected by histology. Interestingly, infectious virus was detected in lung samples for pigs challenged with the parental H1N2 and pH1N1 at levels significantly higher than either reassortant virus despite similar levels of viral RNA. Results of our experiment suggested that the reassortant viruses generated through in vitro cell culture system were attenuated without gaining any selective growth advantage in pigs over the parental lineages. Thus, reassortant influenza viruses described in this study may provide a good system to study genetic basis of the attenuation and its mechanism.

  19. Imaging manifestation of A H1N1 influenza with pneumonia

    International Nuclear Information System (INIS)

    Yang Jun; Xu Yunliang; Lu Zhibin; Wang Xiaojie; Li Shuo; Du Lei; Guo Limin; Li Xingwang

    2010-01-01

    Objective: To evaluate the imaging features of pneumonia caused by A (H1N1) influenza virus. Methods: Imaging data of 51 patients with pneumonia caused by A H1N1 influenza were retrospectively reviewed. All patients underwent mobile chest radiographs and 44 patients underwent CT as well. On the basis of the lesion degree in the lung, the patients were classified into mild, moderate and serious types. Results: Mild type showed patchy consolidation at chest imaging in 4 patients. Moderate type demonstrated consolidation and (or) ground-glass opacities more than 2 lung fields in 33 patients, including 30 bilateral and 3 unilateral. Serious type displayed diffuse consolidation and ground-glass opacities, probably accompanying with interstitial lesions in the lungs in 14 patients, including 6 patients with ARDS, 2 with infection and 1 with cutaneous emphysema. Conclusion: The imaging features of pneumonia caused by A H1N1 influenza mainly manifest as consolidation and ground-glass opacities, probably accompanying with interstitial changes. The imaging findings show various in patients with infection. Some serious patients even develope to ARDS. (authors)

  20. Comparative pathology of pigs infected with Korean H1N1, H1N2, or H3N2 swine influenza A viruses

    OpenAIRE

    Lyoo, Kwang-Soo; Kim, Jeong-Ki; Jung, Kwonil; Kang, Bo-Kyu; Song, Daesub

    2014-01-01

    Background The predominant subtypes of swine influenza A virus (SIV) in Korea swine population are H1N1, H1N2, and H3N2. The viruses are genetically close to the classical U.S. H1N1 and triple-reassortant H1N2 and H3N2 viruses, respectively. Comparative pathogenesis caused by Korean H1N1, H1N2, and H3N2 SIV was evaluated in this study. Findings The H3N2 infected pigs had severe scores of gross and histopathological lesions at post-inoculation days (PID) 2, and this then progressively decrease...

  1. Full-Genome Analysis of Avian Influenza A(H5N1) Virus from a Human, North America, 2013

    Science.gov (United States)

    Pabbaraju, Kanti; Tellier, Raymond; Wong, Sallene; Li, Yan; Bastien, Nathalie; Tang, Julian W.; Drews, Steven J.; Jang, Yunho; Davis, C. Todd; Tipples, Graham A.

    2014-01-01

    Full-genome analysis was conducted on the first isolate of a highly pathogenic avian influenza A(H5N1) virus from a human in North America. The virus has a hemagglutinin gene of clade 2.3.2.1c and is a reassortant with an H9N2 subtype lineage polymerase basic 2 gene. No mutations conferring resistance to adamantanes or neuraminidase inhibitors were found. PMID:24755439

  2. Highly (H5N1 and low (H7N2 pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

    Directory of Open Access Journals (Sweden)

    Kateri Bertran

    Full Text Available An experimental infection with highly pathogenic avian influenza (HPAI and low pathogenic avian influenza (LPAI viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006 or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009, both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR, which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds

  3. Highly (H5N1) and low (H7N2) pathogenic avian influenza virus infection in falcons via nasochoanal route and ingestion of experimentally infected prey.

    Science.gov (United States)

    Bertran, Kateri; Busquets, Núria; Abad, Francesc Xavier; García de la Fuente, Jorge; Solanes, David; Cordón, Iván; Costa, Taiana; Dolz, Roser; Majó, Natàlia

    2012-01-01

    An experimental infection with highly pathogenic avian influenza (HPAI) and low pathogenic avian influenza (LPAI) viruses was carried out on falcons in order to examine the effects of these viruses in terms of pathogenesis, viral distribution in tissues and viral shedding. The distribution pattern of influenza virus receptors was also assessed. Captive-reared gyr-saker (Falco rusticolus x Falco cherrug) hybrid falcons were challenged with a HPAI H5N1 virus (A/Great crested grebe/Basque Country/06.03249/2006) or a LPAI H7N2 virus (A/Anas plathyrhynchos/Spain/1877/2009), both via the nasochoanal route and by ingestion of previously infected specific pathogen free chicks. Infected falcons exhibited similar infection dynamics despite the different routes of exposure, demonstrating the effectiveness of in vivo feeding route. H5N1 infected falcons died, or were euthanized, between 5-7 days post-infection (dpi) after showing acute severe neurological signs. Presence of viral antigen in several tissues was confirmed by immunohistochemistry and real time RT-PCR (RRT-PCR), which were generally associated with significant microscopical lesions, mostly in the brain. Neither clinical signs, nor histopathological findings were observed in any of the H7N2 LPAI infected falcons, although all of them had seroconverted by 11 dpi. Avian receptors were strongly present in the upper respiratory tract of the falcons, in accordance with the consistent oral viral shedding detected by RRT-PCR in both H5N1 HPAI and H7N2 LPAI infected falcons. The present study demonstrates that gyr-saker hybrid falcons are highly susceptible to H5N1 HPAI virus infection, as previously observed, and that they may play a major role in the spreading of both HPAI and LPAI viruses. For the first time in raptors, natural infection by feeding on infected prey was successfully reproduced. The use of avian prey species in falconry husbandry and wildlife rehabilitation facilities could put valuable birds of prey and

  4. Costo-efectividad en la detección de influenza H1N1: datos clínicos versus pruebas rápidas Cost-effectiveness in the detection of influenza H1N1: clinical data versus rapid tests

    Directory of Open Access Journals (Sweden)

    Jorge González-Canudas

    2011-01-01

    Full Text Available OBJETIVO: Evaluar el desempeño de los datos clínicos y la prueba rápida (PR en el diagnóstico de influenza H1N1, y analizar el costo-beneficio que representa el uso de esta herramienta diagnóstica. MÉTODOS: Se aplicó la PR a pacientes que acudieron a cuatro hospitales en la ciudad de México con sintomatología similar a influenza (SSI durante el período octubre y noviembre de 2009. Se comparó el desempeño diagnóstico de la SSI más la PR contra el de la reacción en cadena de la polimerasa en transcripción reversa en tiempo real (rRT-PCR. La rRT-PCR fue procesada en un laboratorio de referencia y cegado al resultado de la PR. Además, se llevó a cabo una evaluación económica a partir de la cual se estimó el impacto presupuestal relacionado con la utilización de la PR RESULTADOS: Se incluyó a 78 pacientes, de los cuales 39 fueron positivos para influenza H1N1 y 6 para influenza A estacional, de acuerdo al resultado de la rRT-PCR. La SSI mostró una sensibilidad de 96% y una especificidad de 21%, la PR de 76% y 82% y el conjunto de SSI más PR de 96% y 100%, respectivamente. El Cociente de Verosimilitud positivo de la SSI-cefalea fue de 31,5 y el de SSI-odinofagia fue de 330. El uso de PR mostró un ahorro de US$ 12,6 por cada caso sospechoso. CONCLUSIONES: El uso de la PR como auxiliar en el diagnóstico de influenza H1N1 incrementa la certeza y reduce el costo promedio por paciente sospechoso e infectado.OBJECTIVE: Evaluate the performance of clinical data and the rapid influenza diagnostic test (RIDT in diagnosing influenza H1N1, and analyze the cost-benefit of using this diagnostic tool. METHODS: The RIDT was used for patients who came to four hospitals in Mexico City with an influenza-like illness (ILI in October and November 2009. The diagnostic performance of the ILI clinical data and the RIDT was compared to that of the real-time reverse transcription polymerase chain reaction (rRT-PCR test. The rRT-PCR test was

  5. Underreporting of 2009 H1N1 Influenza Cases

    Centers for Disease Control (CDC) Podcasts

    Influenza cases are difficult to track because many people don't go to the doctor or get tested for flu when they're sick. The first months of the 2009 H1N1 influenza pandemic were no different. In this podcast, CDC's Dr. Carrie Reed discusses a study in the December issue of Emerging Infectious Diseases that looked at the actual number of cases reported and estimated the true number of cases when correcting for underreporting.

  6. Seroprevalence of H1N1, H3N2 and H1N2 influenza viruses in pigs in seven European countries in 2002-2003.

    Science.gov (United States)

    Van Reeth, Kristien; Brown, Ian H; Dürrwald, Ralf; Foni, Emanuela; Labarque, Geoffrey; Lenihan, Patrick; Maldonado, Jaime; Markowska-Daniel, Iwona; Pensaert, Maurice; Pospisil, Zdenek; Koch, Guus

    2008-05-01

    Avian-like H1N1 and human-like H3N2 swine influenza viruses (SIV) have been considered widespread among pigs in Western Europe since the 1980s, and a novel H1N2 reassortant with a human-like H1 emerged in the mid 1990s. This study, which was part of the EC-funded 'European Surveillance Network for Influenza in Pigs 1', aimed to determine the seroprevalence of the H1N2 virus in different European regions and to compare the relative prevalences of each SIV between regions. Laboratories from Belgium, the Czech Republic, Germany, Italy, Ireland, Poland and Spain participated in an international serosurvey. A total of 4190 sow sera from 651 farms were collected in 2002-2003 and examined in haemagglutination inhibition tests against H1N1, H3N2 and H1N2. In Belgium, Germany, Italy and Spain seroprevalence rates to each of the three SIV subtypes were high (> or =30% of the sows seropositive) to very high (> or =50%), except for a lower H1N2 seroprevalence rate in Italy (13.8%). Most sows in these countries with high pig populations had antibodies to two or three subtypes. In Ireland, the Czech Republic and Poland, where swine farming is less intensive, H1N1 was the dominant subtype (8.0-11.7% seropositives) and H1N2 and H3N2 antibodies were rare (0-4.2% seropositives). Thus, SIV of H1N1, H3N2 and H1N2 subtype are enzootic in swine producing regions of Western Europe. In Central Europe, SIV activity is low and the circulation of H3N2 and H1N2 remains to be confirmed. The evolution and epidemiology of SIV throughout Europe is being further monitored through a second 'European Surveillance Network for Influenza in Pigs'.

  7. An Impedance Aptasensor with Microfluidic Chips for Specific Detection of H5N1 Avian Influenza Virus

    Directory of Open Access Journals (Sweden)

    Jacob Lum

    2015-07-01

    Full Text Available In this research a DNA aptamer, which was selected through SELEX (systematic evolution of ligands by exponential enrichment to be specific against the H5N1 subtype of the avian influenza virus (AIV, was used as an alternative reagent to monoclonal antibodies in an impedance biosensor utilizing a microfluidics flow cell and an interdigitated microelectrode for the specific detection of H5N1 AIV. The gold surface of the interdigitated microelectrode embedded in a microfluidics flow cell was modified using streptavidin. The biotinylated aptamer against H5N1 was then immobilized on the electrode surface using biotin–streptavidin binding. The target virus was captured on the microelectrode surface, causing an increase in impedance magnitude. The aptasensor had a detection time of 30 min with a detection limit of 0.0128 hemagglutinin units (HAU. Scanning electron microscopy confirmed the binding of the target virus onto the electrode surface. The DNA aptamer was specific to H5N1 and had no cross-reaction to other subtypes of AIV (e.g., H1N1, H2N2, H7N2. The newly developed aptasensor offers a portable, rapid, low-cost alternative to current methods with the same sensitivity and specificity.

  8. Risk of Human Infections With Highly Pathogenic H5N2 and Low Pathogenic H7N1 Avian Influenza Strains During Outbreaks in Ostriches in South Africa.

    Science.gov (United States)

    Venter, Marietjie; Treurnicht, Florette K; Buys, Amelia; Tempia, Stefano; Samudzi, Rudo; McAnerney, Johanna; Jacobs, Charlene A; Thomas, Juno; Blumberg, Lucille

    2017-09-15

    Risk factors for human infection with highly pathogenic (HP) and low-pathogenic (LP) avian influenza (AI) H5N2 and H7N1 were investigated during outbreaks in ostriches in the Western Cape province, South Africa. Serum surveys were conducted for veterinarians, farmworkers, and laboratory and abattoir workers involved in 2 AI outbreaks in the Western Cape province: (1) controlling and culling of 42000 ostriches during (HPAI)H5N2 outbreaks in ostriches (2011) (n = 207); (2) movement control during (LPAI)H7N1 outbreaks in 2012 (n = 66). A third serosurvey was conducted on state veterinarians from across the country in 2012 tasked with disease control in general (n = 37). Antibodies to H5 and H7 were measured by means of hemagglutination inhibition and microneutralization assays, with microneutralization assay titers >40 considered positive. Two of 207 (1%) participants were seropositive for H5 and 4 of 207 (2%) for H7 in 2011, compared with 1 of 66 (1.5%) and 8 of 66 (13%) in 2012. Although individuals in all professions tested seropositive, abattoir workers (10 of 97; 10.3%) were significantly more at risk of influenza A(H7N1) infection (P = .001) than those in other professions (2 of 171;1.2%). Among state veterinarians, 4 of 37(11%) were seropositive for H7 and 1 of 37 (2.7%) for H5. Investigations of (LP)H7N1-associated fatalities in wild birds and quarantined exotic birds in Gauteng, AI outbreaks in poultry in KwaZulu-Natal, and ostriches in Western Cape province provide possible exposure events. (LPAI)H7N1 strains pose a greater infection-risk than (HPAI)H5N2 strains to persons involved in control of outbreaks in infected birds, with ostrich abattoir workers at highest risk. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.

  9. Indium-tin-oxide thin film transistor biosensors for label-free detection of avian influenza virus H5N1

    International Nuclear Information System (INIS)

    Guo, Di; Zhuo, Ming; Zhang, Xiaoai; Xu, Cheng; Jiang, Jie; Gao, Fu; Wan, Qing; Li, Qiuhong; Wang, Taihong

    2013-01-01

    Highlights: ► A highly selective label-free biosensor is established based on indium-tin-oxide thin-film transistors (ITO TFTs). ► AI H5N1 virus was successfully detected through shift in threshold voltage and field-effect mobility of ITO TFT. ► The ITO TFT is applied in biosensor for the first time and shows good reusability and stability. ► Fabrication of the platform is simple with low cost, which is suitable for mass commercial production. -- Abstract: As continuous outbreak of avian influenza (AI) has become a threat to human health, economic development and social stability, it is urgently necessary to detect the highly pathogenic avian influenza H5N1 virus quickly. In this study, we fabricated indium-tin-oxide thin-film transistors (ITO TFTs) on a glass substrate for the detecting of AI H5N1. The ITO TFT is fabricated by a one-shadow-mask process in which a channel layer can be simultaneously self-assembled between ITO source/drain electrodes during magnetron sputtering deposition. Monoclonal anti-H5N1 antibodies specific for AI H5N1 virus were covalently immobilized on the ITO channel by (3-glycidoxypropyl)trimethoxysilane. The introduction of target AI H5N1 virus affected the electronic properties of the ITO TFT, which caused a change in the resultant threshold voltage (V T ) and field-effect mobility. The changes of I D –V G curves were consistent with an n-type field effect transistor behavior affected by nearby negatively charged AI H5N1 viruses. The transistor based sensor demonstrated high selectivity and stability for AI H5N1 virus sensing. The sensor showed linear response to AI H5N1 in the concentrations range from 5 × 10 −9 g mL −1 to 5 × 10 −6 g mL −1 with a detection limit of 0.8 × 10 −10 g mL −1 . Moreover, the ITO TFT biosensors can be repeatedly used through the washing processes. With its excellent electric properties and the potential for mass commercial production, ITO TFTs can be promising candidates for the

  10. Immunomodulatory Activity and Protective Effects of Polysaccharide from Eupatorium adenophorum Leaf Extract on Highly Pathogenic H5N1 Influenza Infection

    Directory of Open Access Journals (Sweden)

    Yi Jin

    2013-01-01

    Full Text Available The development of novel broad-spectrum, antiviral agents against H5N1 infection is urgently needed. In this study, we evaluated the immunomodulatory activities and protective effect of Eupatorium adenophorum polysaccharide (EAP against the highly pathogenic H5N1 subtype influenza virus. EAP treatment significantly increased the production of IL-6, TNF-α, and IFN-γ both in vivo and in vitro as measured by qPCR and ELISA. In a mouse infection model, intranasal administration of EAP at a dose of 25 mg/kg body weight prior to H5N1 viral challenge efficiently inhibited viral replication, decreased lung lesions, and increased survival rate. We further evaluated the innate immune recognition of EAP, as this process is regulated primarily Dectin-1 and mannose receptor (MR. These results indicate that EAP may have immunomodulatory properties and a potential prophylactic effect against H5N1 influenza infection. Our investigation suggests an alternative strategy for the development of novel antiinfluenza agents and benefits of E. adenophorum products.

  11. Novel reassortant influenza A(H1N2) virus derived from A(H1N1)pdm09 virus isolated from swine, Japan, 2012.

    Science.gov (United States)

    Kobayashi, Miho; Takayama, Ikuyo; Kageyama, Tsutomu; Tsukagoshi, Hiroyuki; Saitoh, Mika; Ishioka, Taisei; Yokota, Yoko; Kimura, Hirokazu; Tashiro, Masato; Kozawa, Kunihisa

    2013-12-01

    We isolated a novel influenza virus A(H1N2) strain from a pig on January 13, 2012, in Gunma Prefecture, Japan. Phylogenetic analysis showed that the strain was a novel type of double-reassortant virus derived from the swine influenza virus strains H1N1pdm09 and H1N2, which were prevalent in Gunma at that time.

  12. Prevalence and risk factors for H1N1 and H3N2 influenza A virus infections in Minnesota turkey premises.

    Science.gov (United States)

    Corzo, Cesar A; Gramer, Marie; Lauer, Dale; Davies, Peter R

    2012-09-01

    Influenza virus infections can cause respiratory and systemic disease of variable severity and also result in economic losses for the turkey industry. Several subtypes of influenza can infect turkeys, causing diverse clinical signs. Influenza subtypes of swine origin have been diagnosed in turkey premises; however, it is not known how common these infections are nor the likely routes of transmission. We conducted a cross-sectional study to estimate the prevalence of influenza viruses and examine factors associated with infection on Minnesota turkey premises. Results from influenza diagnostic tests and turkey and pig premise location data were obtained from the Minnesota Poultry Testing Laboratory and the Minnesota Board of Animal Health, respectively, from January 2007 to September 2008. Diagnostic data from 356 premises were obtained, of which 17 premises tested positive for antibodies to influenza A virus by agar gel immunodiffusion assay and were confirmed as either H1N1 or H3N2 influenza viruses by hemagglutination and neuraminidase inhibition assays. Influenza infection status was associated with proximity to pig premises and flock size. The latter had a sparing effect on influenza status. This study suggests that H1N1 and H3N2 influenza virus infections of turkey premises in Minnesota are an uncommon event. The route of influenza virus transmission could not be determined; however, the findings suggest that airborne transmission should be considered in future studies.

  13. Molecular characterization of a novel reassortant H1N2 influenza virus containing genes from the 2009 pandemic human H1N1 virus in swine from eastern China.

    Science.gov (United States)

    Peng, Xiuming; Wu, Haibo; Xu, Lihua; Peng, Xiaorong; Cheng, Linfang; Jin, Changzhong; Xie, Tiansheng; Lu, Xiangyun; Wu, Nanping

    2016-06-01

    Pandemic outbreaks of H1N1 swine influenza virus have been reported since 2009. Reassortant H1N2 viruses that contain genes from the pandemic H1N1 virus have been isolated in Italy and the United States. However, there is limited information regarding the molecular characteristics of reassortant H1N2 swine influenza viruses in eastern China. Active influenza surveillance programs in Zhejiang Province identified a novel H1N2 influenza virus isolated from pigs displaying clinical signs of influenza virus infection. Whole-genome sequencing was performed and this strain was compared with other influenza viruses available in GenBank. Phylogenetic analysis suggested that the novel strain contained genes from the 2009 pandemic human H1N1 and swine H3N2 viruses. BALB/c mice were infected with the isolated virus to assess its virulence in mice. While the novel H1N2 isolate replicated well in mice, it was found to be less virulent. These results provide additional evidence that swine serve as intermediate hosts or 'mixing vessels' for novel influenza viruses. They also emphasize the importance of surveillance in the swine population for use as an early warning system for influenza outbreaks in swine and human populations.

  14. An induced pocket for the binding of potent fusion inhibitor CL-385319 with H5N1 influenza virus hemagglutinin.

    Directory of Open Access Journals (Sweden)

    Runming Li

    Full Text Available The influenza glycoprotein hemagglutinin (HA plays crucial roles in the early stage of virus infection, including receptor binding and membrane fusion. Therefore, HA is a potential target for developing anti-influenza drugs. Recently, we characterized a novel inhibitor of highly pathogenic H5N1 influenza virus, CL-385319, which specifically inhibits HA-mediated viral entry. Studies presented here identified the critical binding residues for CL-385319, which clustered in the stem region of the HA trimer by site-directed mutagenesis. Extensive computational simulations, including molecular docking, molecular dynamics simulations, molecular mechanics generalized Born surface area (MM_GBSA calculations, charge density and Laplacian calculations, have been carried out to uncover the detailed molecular mechanism that underlies the binding of CL-385319 to H5N1 influenza virus HA. It was found that the recognition and binding of CL-385319 to HA proceeds by a process of "induced fit" whereby the binding pocket is formed during their interaction. Occupation of this pocket by CL-385319 stabilizes the neutral pH structure of hemagglutinin, thus inhibiting the conformational rearrangements required for membrane fusion. This "induced fit" pocket may be a target for structure-based design of more potent influenza fusion inhibitors.

  15. Comparison of ARIMA and Random Forest time series models for prediction of avian influenza H5N1 outbreaks.

    Science.gov (United States)

    Kane, Michael J; Price, Natalie; Scotch, Matthew; Rabinowitz, Peter

    2014-08-13

    Time series models can play an important role in disease prediction. Incidence data can be used to predict the future occurrence of disease events. Developments in modeling approaches provide an opportunity to compare different time series models for predictive power. We applied ARIMA and Random Forest time series models to incidence data of outbreaks of highly pathogenic avian influenza (H5N1) in Egypt, available through the online EMPRES-I system. We found that the Random Forest model outperformed the ARIMA model in predictive ability. Furthermore, we found that the Random Forest model is effective for predicting outbreaks of H5N1 in Egypt. Random Forest time series modeling provides enhanced predictive ability over existing time series models for the prediction of infectious disease outbreaks. This result, along with those showing the concordance between bird and human outbreaks (Rabinowitz et al. 2012), provides a new approach to predicting these dangerous outbreaks in bird populations based on existing, freely available data. Our analysis uncovers the time-series structure of outbreak severity for highly pathogenic avain influenza (H5N1) in Egypt.

  16. Initial psychological responses to Influenza A, H1N1 ("Swine flu"

    Directory of Open Access Journals (Sweden)

    Neto Felix

    2009-10-01

    Full Text Available Abstract Background The outbreak of the pandemic flu, Influenza A H1N1 (Swine Flu in early 2009, provided a major challenge to health services around the world. Previous pandemics have led to stockpiling of goods, the victimisation of particular population groups, and the cancellation of travel and the boycotting of particular foods (e.g. pork. We examined initial behavioural and attitudinal responses towards Influenza A, H1N1 ("Swine flu" in the six days following the WHO pandemic alert level 5, and regional differences in these responses. Methods 328 respondents completed a cross-sectional Internet or paper-based questionnaire study in Malaysia (N = 180 or Europe (N = 148. Measures assessed changes in transport usage, purchase of preparatory goods for a pandemic, perceived risk groups, indicators of anxiety, assessed estimated mortality rates for seasonal flu, effectiveness of seasonal flu vaccination, and changes in pork consumption Results 26% of the respondents were 'very concerned' about being a flu victim (42% Malaysians, 5% Europeans, p Conclusion Initial responses to Influenza A show large regional differences in anxiety, with Malaysians more anxious and more likely to reduce travel and to buy masks and food. Discussions with family and friends may reinforce existing anxiety levels. Particular groups (homosexuals, prostitutes, the homeless are perceived as at greater risk, potentially leading to increased prejudice during a pandemic. Europeans underestimated mortality of seasonal flu, and require more information about the protection given by seasonal flu inoculation.

  17. Long term immune responses to pandemic influenza A/H1N1 infection in solid organ transplant recipients.

    Directory of Open Access Journals (Sweden)

    Aliyah Baluch

    Full Text Available In solid organ transplant (SOT recipients it is unknown if natural infection with influenza confers protection from re-infection with the same strain during the next influenza season. The purpose of this study was to determine if infection with pandemic influenza A/H1N1 (pH1N1 resulted in a long-term immunologic response. Transplant recipients with microbiologically proven pH1N1 infection in 2009/2010 underwent humoral and cell-mediated immunity (CMI testing for pH1N1 just prior to the next influenza season. Concurrent testing for A/Brisbane/59/2007 was done to rule-out cross-reacting antibody. We enrolled 22 adult transplant patients after pH1N1 infection. Follow up testing was done at a median of 7.4 months (range 5.8-15.4 after infection. After excluding those with cross-reactive antibody, 7/19 (36.8% patients were seroprotected. Detectable pH1N1-specific CD4+ and CD8+ interferon-γ producing T-cells were found in 11/22 (50% and 8/22 (36.4% patients respectively. Humoral immunity had a significant correlation with a CD4 response. This is the first study in transplant patients to evaluate long-term humoral and cellular response after natural influenza infection. We show that a substantial proportion of SOT recipients with previous pH1N1 infection lack long-term humoral and cellular immune responses to pH1N1. These patients most likely are at risk for re-infection.

  18. Outbreak of influenza type A (H1N1 in Iporanga, São Paulo State, Brazil Epidemia de influenza A (H1N1 no Município de Iporanga, SP, Brasil

    Directory of Open Access Journals (Sweden)

    Terezinha Maria de PAIVA

    2001-12-01

    Full Text Available From June to July 1999 an outbreak of acute respiratory illness occurred in the town of Iporanga. Out of a total of 4,837 inhabitants, 324 cases were notified to the Regional Surveillance Service. Influenza virus was isolated from 57.1% of the collected samples and 100% seroconversion to influenza A (H1N1 was obtained in 20 paired sera tested. The isolates were related to the A/Bayern/07/95 strain (H1N1. The percentages of cases notified during the outbreak were 28.4%, 29.0%, 20.7%, 6.2% and 15.7% in the age groups of 0-4, 5-9, 10-14, 15-19 and older than 20 years, respectively. The highest proportion of positives was observed among children younger than 14 years and no cases were notified in people older than 65 years, none of whom had been recently vaccinated against influenza. These findings suggest a significant vaccine protection against A/Bayern/7/95, the H1 component included in the 1997-98 influenza vaccine for elderly people. This viral strain is antigenically and genetically related to A/Beijing/262/95, the H1 component of the 1999 vaccine. Vaccines containing A/Beijing/262/95 (H1N1 stimulated post-immunization hemagglutination inhibition antibodies equivalent in frequency and titre to both A/Beijing/262/95-like and A/Bayern/7/95-like viruses. Thus, this investigation demonstrates the effectiveness of vaccination against influenza virus in the elderly.Durante os meses de junho e julho de 1999, foram notificados 324 casos de doença respiratória aguda no Município de Iporanga-SP. O isolamento do vírus da influenza do tipo A/Bayern/07/95 (H1N1 e a conversão sorológica para a estirpe viral (H1N1 foram de 57,1% e 100%, respectivamente. A porcentagem de casos com diagnóstico clínico notificados durante a epidemia foi de 28,4%, 29,0%, 20,7%, 6,2% e 15,7%, nas faixas etárias de 0-4, 5-9, 10-14, 15-19 anos e indivíduos acima de 20 anos de idade, respectivamente. Observou-se maior incidência da doença entre os indivíduos menores de

  19. Kompliceret influenza A (H1N1) hos gravid i andet trimester

    DEFF Research Database (Denmark)

    Ersboell, Anne Schjoedt; Hesselvig, Anne Brun; Hedegaard, Morten

    2012-01-01

    A 27-year-old woman at 25 weeks of gestation was admitted to hospital due to bilateral pneumonia with increasing hypoxia. She was tested positive for influenza A (H1N1) and successfully treated with oral oseltamivir. Nine days after the admission pathological umbilical flows were recorded...... and an emergency caesarean was performed at 26 weeks + 2 days of gestation. The neonatal period was uncomplicated. Influenza A (H1N1) is especially dangerous in pregnant women and vaccination is important....

  20. Probable transmisión vertical del virus de la influenza A (H1N1: a propósito de un caso Probable vertical transmission of the influenza virus A (H1N1: apropos of a case

    Directory of Open Access Journals (Sweden)

    Rubén D. Vásquez

    2010-09-01

    Full Text Available Se reporta el caso de un recién nacido varón, producto de embarazo de 36 semanas, con diagnóstico de neumonía congénita y examen confirmatorio de infección por el virus de la influenza A (H1N1, sin ningún otro tipo de contacto sospechoso. La madre ingresó al hospital con insuficiencia respiratoria y antecedente de proceso gripal de cinco días de evolución, durante los primeros días de la pandemia en el Perú. Por la evolución grave del proceso respiratorio, se le administró ventilación mecánica para luego ser sometida a cesárea por sufrimiento fetal agudo y oligoamnios. Se confirmó en la madre infección por el virus de la influenza A H1N1 epidémico y tuberculosis pulmonar.We report the case of a male newborn, product of a 36 week pregnancy, with diagnosis of congenital pneumonia and with a confirmatory test for influenza A (H1N1 virus, without any other suspicious contact. The mother was admitted to the hospital with respiratory failure and the history of a flu-like episode of 5 days of evolution, during the first days of the pandemic in Peru. Due to the severe evolution of the respiratory process, assisted ventilation was given to her and then a cesarean section was performed due to acute fetal distress and oligoamnios. The mother was later confirmed as a case of epidemic influenza A (H1N1 and pulmonary tuberculosis.

  1. Highly pathogenic avian influenza A (H5N1) virus in wildlife: diagnostics, epidemiology and molecular characteristics

    NARCIS (Netherlands)

    Keawcharoen, J.

    2010-01-01

    Since 2003, highly pathogenic avian influenza virus subtype H5N1 outbreaks have been reported in Southeast Asia causing high mortality in poultry and have also been found to cross the species barrier infecting human and other mammalian species. Thailand is one of the countries severely affected by

  2. Modeling and roles of meteorological factors in outbreaks of highly pathogenic avian influenza H5N1.

    Directory of Open Access Journals (Sweden)

    Paritosh K Biswas

    Full Text Available The highly pathogenic avian influenza A virus subtype H5N1 (HPAI H5N1 is a deadly zoonotic pathogen. Its persistence in poultry in several countries is a potential threat: a mutant or genetically reassorted progenitor might cause a human pandemic. Its world-wide eradication from poultry is important to protect public health. The global trend of outbreaks of influenza attributable to HPAI H5N1 shows a clear seasonality. Meteorological factors might be associated with such trend but have not been studied. For the first time, we analyze the role of meteorological factors in the occurrences of HPAI outbreaks in Bangladesh. We employed autoregressive integrated moving average (ARIMA and multiplicative seasonal autoregressive integrated moving average (SARIMA to assess the roles of different meteorological factors in outbreaks of HPAI. Outbreaks were modeled best when multiplicative seasonality was incorporated. Incorporation of any meteorological variable(s as inputs did not improve the performance of any multivariable models, but relative humidity (RH was a significant covariate in several ARIMA and SARIMA models with different autoregressive and moving average orders. The variable cloud cover was also a significant covariate in two SARIMA models, but air temperature along with RH might be a predictor when moving average (MA order at lag 1 month is considered.

  3. Direct isolation of H1N2 recombinant virus from a throat swab of a patient simultaneously infected with H1N1 and H3N2 influenza A viruses.

    OpenAIRE

    Nishikawa, F; Sugiyama, T

    1983-01-01

    Two H1N2 recombinant viruses were isolated by a plaquing method from a throat swab of a patient who was simultaneously infected with H1N1 and H3N2 influenza viruses during the Tokyo epidemic of 1981. This is the first direct evidence that recombination of influenza viruses occurred in the human body.

  4. Ecological Determinants of Highly Pathogenic Avian Influenza (H5N1) Outbreaks in Bangladesh

    Science.gov (United States)

    Ahmed, Syed S. U.; Ersbøll, Annette K.; Biswas, Paritosh K.; Christensen, Jens P.; Hannan, Abu S. M. A.; Toft, Nils

    2012-01-01

    Background The agro-ecology and poultry husbandry of the south Asian and south-east Asian countries share common features, however, with noticeable differences. Hence, the ecological determinants associated with risk of highly pathogenic avian influenza (HPAI-H5N1) outbreaks are expected to differ between Bangladesh and e.g., Thailand and Vietnam. The primary aim of the current study was to establish ecological determinants associated with the risk of HPAI-H5N1 outbreaks at subdistrict level in Bangladesh. The secondary aim was to explore the performance of two different statistical modeling approaches for unmeasured spatially correlated variation. Methodology/Principal Findings An ecological study at subdistrict level in Bangladesh was performed with 138 subdistricts with HPAI-H5N1 outbreaks during 2007–2008, and 326 subdistricts with no outbreaks. The association between ecological determinants and HPAI-H5N1 outbreaks was examined using a generalized linear mixed model. Spatial clustering of the ecological data was modeled using 1) an intrinsic conditional autoregressive (ICAR) model at subdistrict level considering their first order neighbors, and 2) a multilevel (ML) model with subdistricts nested within districts. Ecological determinants significantly associated with risk of HPAI-H5N1 outbreaks at subdistrict level were migratory birds' staging areas, river network, household density, literacy rate, poultry density, live bird markets, and highway network. Predictive risk maps were derived based on the resulting models. The resulting models indicate that the ML model absorbed some of the covariate effect of the ICAR model because of the neighbor structure implied in the two different models. Conclusions/Significance The study identified a new set of ecological determinants related to river networks, migratory birds' staging areas and literacy rate in addition to already known risk factors, and clarified that the generalized concept of free grazing duck and

  5. Persistence of highly pathogenic avian influenza H5N1 virus defined by agro-ecological niche

    Science.gov (United States)

    Hogerwerf, Lenny; Wallace, Rob G.; Ottaviani, Daniela; Slingenbergh, Jan; Prosser, Diann; Bergmann, Luc; Gilbert, Marius

    2010-01-01

    The highly pathogenic avian influenza (HPAI) H5N1 virus has spread across Eurasia and into Africa. Its persistence in a number of countries continues to disrupt poultry production, impairs smallholder livelihoods, and raises the risk a genotype adapted to human-to-human transmission may emerge. While previous studies identified domestic duck reservoirs as a primary risk factor associated with HPAI H5N1 persistence in poultry in Southeast Asia, little is known of such factors in countries with different agro-ecological conditions, and no study has investigated the impact of such conditions on HPAI H5N1 epidemiology at the global scale. This study explores the patterns of HPAI H5N1 persistence worldwide, and for China, Indonesia, and India includes individual provinces that have reported HPAI H5N1 presence during the 2004–2008 period. Multivariate analysis of a set of 14 agricultural, environmental, climatic, and socio-economic factors demonstrates in quantitative terms that a combination of six variables discriminates the areas with human cases and persistence: agricultural population density, duck density, duck by chicken density, chicken density, the product of agricultural population density and chicken output/input ratio, and purchasing power per capita. The analysis identifies five agro-ecological clusters, or niches, representing varying degrees of disease persistence. The agro-ecological distances of all study areas to the medoid of the niche with the greatest number of human cases are used to map HPAI H5N1 risk globally. The results indicate that few countries remain where HPAI H5N1 would likely persist should it be introduced.

  6. Development of a diagnostic kit for Tamiflu-resistant influenza A (H1N1)

    International Nuclear Information System (INIS)

    Jung, I. L.; Hong, S. W.

    2012-01-01

    Swine influenza A, which has been pandemic worldwide since 2009, is a new type virus derived from A type influenza. Although some drugs against the contageous disease, such as relenza and tamiflu, have been commercialized, those drug resistant viruses could be also followed by the wide usage of drugs. For examples, Tamiflu-resistant viruses, the mutant type viruses, can not be cured by the treatment of tamiflu anymore. Thus, a quick diagnosis for the wild type (tamiflu-sensitive) and mutant (tamiflu-resistant) virus would be essential in order to prevent the wide spread of viruses. In spite of that, unfortunately, very few studies have been conducted until now. If we could tell the differences between tamiflu-resistant and -sensitive patients using by the proper diagnostic kit, not only patient specific treatment would be possible, but also the spread of viruses would be effectively prevented. Currently used detection methods for the swine influenza A H1N1, which were originated from CDC, USA, can not detect the tamiflu-resistant swine influenza A H1N1, but only can detect tamiflu-sensitive wine influenza A H1N1. In this study, all the primers for the detection of swInfA, swH1, MP and NA (neuraminidase) have been developed in order to detect both tamiflu-resistant and tamiflu-sensitive swine influenza A H1N1s simultaneously, and then, new multiplex RT-PCR methods has been established

  7. Development of a diagnostic kit for Tamiflu-resistant influenza A (H1N1)

    Energy Technology Data Exchange (ETDEWEB)

    Jung, I. L.; Hong, S. W.

    2012-01-15

    Swine influenza A, which has been pandemic worldwide since 2009, is a new type virus derived from A type influenza. Although some drugs against the contageous disease, such as relenza and tamiflu, have been commercialized, those drug resistant viruses could be also followed by the wide usage of drugs. For examples, Tamiflu-resistant viruses, the mutant type viruses, can not be cured by the treatment of tamiflu anymore. Thus, a quick diagnosis for the wild type (tamiflu-sensitive) and mutant (tamiflu-resistant) virus would be essential in order to prevent the wide spread of viruses. In spite of that, unfortunately, very few studies have been conducted until now. If we could tell the differences between tamiflu-resistant and -sensitive patients using by the proper diagnostic kit, not only patient specific treatment would be possible, but also the spread of viruses would be effectively prevented. Currently used detection methods for the swine influenza A H1N1, which were originated from CDC, USA, can not detect the tamiflu-resistant swine influenza A H1N1, but only can detect tamiflu-sensitive wine influenza A H1N1. In this study, all the primers for the detection of swInfA, swH1, MP and NA (neuraminidase) have been developed in order to detect both tamiflu-resistant and tamiflu-sensitive swine influenza A H1N1s simultaneously, and then, new multiplex RT-PCR methods has been established.

  8. Usefulness of CURB-65 and pneumonia severity index for influenza A H1N1v pneumonia.

    Science.gov (United States)

    Estella, A

    2012-01-01

    Usefulness of CURB-65 and pneumonia severity index for influenza A H1N1v pneumonia. A. Estella. Different prognostic scales have been documented to assess the severity and indications for hospitalization and ICU admissions of community acquired pneumonia. During the past two years Influenza A H1N1v infections have been commonly attended to in emergency departments. The aim of the study was to analyse the usefulness of the application of the Pneumonia Severity Index (PSI) and CURB-65 prognostic scales in patients with primary viral pneumonia caused by influenza A H1N1v. A retrospective study was performed at a community hospital with a 17 bed-intensive care unit. Patients admitted in hospital with influenza A H1N1v pneumonia over a two year period were analysed. CURB 65 and PSI scales were applied in the emergency department and outcome and destination of admission were analysed. 24 patients were registered, 19 required ICU admission and 5 patients were admitted in medical wards. Most of the patients admitted to the intensive care unit (78.9%) required mechanical ventilation. Mortality was 21.1%. Most patients admitted to the ICU had CURB 65 scale of 1 (60%), 13.3% obtained 0 and 26.7% 2. PSI scale resulted class I in a 20%, class II 40%, 26.7% class IV and 13.3% class V. The scales CURB 65 and PSI showed no differences in scores according to the destination of admission and mortality. Use of CURB-65 and PSI in the emergency department may underestimate the risk of patients with Influenza A H1N1v pneumonia. Based in our results, the ability of these scales to predict ICU admissions for Influenza A H1N1v pneumonia is questioned.

  9. Effect of neuraminidase inhibitor-resistant mutations on pathogenicity of clade 2.2 A/Turkey/15/06 (H5N1 influenza virus in ferrets.

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    Natalia A Ilyushina

    2010-05-01

    Full Text Available The acquisition of neuraminidase (NA inhibitor resistance by H5N1 influenza viruses has serious clinical implications, as this class of drugs can be an essential component of pandemic control measures. The continuous evolution of the highly pathogenic H5N1 influenza viruses results in the emergence of natural NA gene variations whose impact on viral fitness and NA inhibitor susceptibility are poorly defined. We generated seven genetically stable recombinant clade 2.2 A/Turkey/15/06-like (H5N1 influenza viruses carrying NA mutations located either in the framework residues (E119A, H274Y, N294S or in close proximity to the NA enzyme active site (V116A, I117V, K150N, Y252H. NA enzyme inhibition assays showed that NA mutations at positions 116, 117, 274, and 294 reduced susceptibility to oseltamivir carboxylate (IC(50s increased 5- to 940-fold. Importantly, the E119A NA mutation (previously reported to confer resistance in the N2 NA subtype was stable in the clade 2.2 H5N1 virus background and induced cross-resistance to oseltamivir carboxylate and zanamivir. We demonstrated that Y252H NA mutation contributed for decreased susceptibility of clade 2.2 H5N1 viruses to oseltamivir carboxylate as compared to clade 1 viruses. The enzyme kinetic parameters (V(max, K(m and K(i of the avian-like N1 NA glycoproteins were highly consistent with their IC(50 values. None of the recombinant H5N1 viruses had attenuated virulence in ferrets inoculated with 10(6 EID(50 dose. Most infected ferrets showed mild clinical disease signs that differed in duration. However, H5N1 viruses carrying the E119A or the N294S NA mutation were lethal to 1 of 3 inoculated animals and were associated with significantly higher virus titers (P<0.01 and inflammation in the lungs compared to the wild-type virus. Our results suggest that highly pathogenic H5N1 variants carrying mutations within the NA active site that decrease susceptibility to NA inhibitors may possess increased

  10. An analysis of 332 fatalities infected with pandemic 2009 influenza A (H1N1 in Argentina.

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    Ana M Balanzat

    Full Text Available The apparent high number of deaths in Argentina during the 2009 pandemic led to concern that the influenza A H1N1pdm disease was different there. We report the characteristics and risk factors for influenza A H1N1pdm fatalities.We identified laboratory-confirmed influenza A H1N1pdm fatalities occurring during June-July 2009. Physicians abstracted data on age, sex, time of onset of illness, medical history, clinical presentation at admission, laboratory, treatment, and outcomes using standardize questionnaires. We explored the characteristics of fatalities according to their age and risk group.Of 332 influenza A H1N1pdm fatalities, 226 (68% were among persons aged <50 years. Acute respiratory failure was the leading cause of death. Of all cases, 249 (75% had at least one comorbidity as defined by Advisory Committee on Immunization Practices. Obesity was reported in 32% with data and chronic pulmonary disease in 28%. Among the 40 deaths in children aged <5 years, chronic pulmonary disease (42% and neonatal pathologies (35% were the most common co-morbidities. Twenty (6% fatalities were among pregnant or postpartum women of which only 47% had diagnosed co-morbidities. Only 13% of patients received antiviral treatment within 48 hours of symptom onset. None of children aged <5 years or the pregnant women received antivirals within 48 h of symptom onset. As the pandemic progressed, the time from symptom-onset to medical care and to antiviral treatment decreased significantly among case-patients who subsequently died (p<0.001.Persons with co-morbidities, pregnant and who received antivirals late were over-represented among influenza A H1N1pdm deaths in Argentina, though timeliness of antiviral treatment improved during the pandemic.

  11. Genetic Characterization of Influenza A (H1N1) Pandemic 2009 Virus Isolates from Mumbai.

    Science.gov (United States)

    Gohil, Devanshi; Kothari, Sweta; Shinde, Pramod; Meharunkar, Rhuta; Warke, Rajas; Chowdhary, Abhay; Deshmukh, Ranjana

    2017-08-01

    Pandemic influenza A (H1N1) 2009 virus was first detected in India in May 2009 which subsequently became endemic in many parts of the country. Influenza A viruses have the ability to evade the immune response through its ability of antigenic variations. The study aims to characterize influenza A (H1N1) pdm 09 viruses circulating in Mumbai during the pandemic and post-pandemic period. Nasopharyngeal swabs positive for influenza A (H1N1) pdm 09 viruses were inoculated on Madin-Darby canine kidney cell line for virus isolation. Molecular and phylogenetic analysis of influenza A (H1N1) pdm 09 isolates was conducted to understand the evolution and genetic diversity of the strains. Nucleotide and amino acid sequences of the HA gene of Mumbai isolates when compared to A/California/07/2009-vaccine strain revealed 14 specific amino acid differences located at the antigenic sites. Amino acid variations in HA and NA gene resulted in changes in the N-linked glycosylation motif which may lead to immune evasion. Phylogenetic analysis of the isolates revealed their evolutionary position with vaccine strain A/California/07/2009 but had undergone changes gradually. The findings in the present study confirm genetic variability of influenza viruses and highlight the importance of continuous surveillance during influenza outbreaks.

  12. Public health concerns of highly pathogenic avian influenza H5N1 endemicity in Africa

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    Olubunmi Gabriel Fasanmi

    2017-10-01

    Full Text Available Highly pathogenic avian influenza virus (HPAIV H5N1 was first officially reported in Africa in 2006; thereafter this virus has spread rapidly from Nigeria to 11 other African countries. This study was aimed at utilizing data from confirmed laboratory reports to carry out a qualitative evaluation of the factors responsible for HPAI H5N1 persistence in Africa and the public health implications; and to suggest appropriate control measures. Relevant publications were sought from data banks and repositories of FAO, OIE, WHO, and Google scholars. Substantiated data on HPAI H5N1 outbreaks in poultry in Africa and in humans across the world were mined. HPAI H5N1 affects poultry and human populations, with Egypt having highest human cases (346 globally. Nigeria had a reinfection from 2014 to 2015, with outbreaks in Cote d'Ivoire, Ghana, Niger, Nigeria, and Burkina Faso throughout 2016 unabated. The persistence of this virus in Africa is attributed to the survivability of HPAIV, ability to evolve other subtypes through genetic reassortment, poor biosecurity compliance at the live bird markets and poultry farms, husbandry methods and multispecies livestock farming, poultry vaccinations, and continuous shedding of HPAIV, transboundary transmission of HPAIV through poultry trades; and transcontinental migratory birds. There is, therefore, the need for African nations to realistically reassess their status, through regular surveillance and be transparent with HPAI H5N1 outbreak data. Also, it is important to have an understanding of HPAIV migration dynamics which will be helpful in epidemiological modeling, disease prevention, control and eradication measures.

  13. An M2e-based multiple antigenic peptide vaccine protects mice from lethal challenge with divergent H5N1 influenza viruses

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    Chan Chris CS

    2010-01-01

    Full Text Available Abstract Background A growing concern has raised regarding the pandemic potential of the highly pathogenic avian influenza (HPAI H5N1 viruses. Consequently, there is an urgent need to develop an effective and safe vaccine against the divergent H5N1 influenza viruses. In the present study, we designed a tetra-branched multiple antigenic peptide (MAP-based vaccine, designated M2e-MAP, which contains the sequence overlapping the highly conserved extracellular domain of matrix protein 2 (M2e of a HPAI H5N1 virus, and investigated its immune responses and cross-protection against different clades of H5N1 viruses. Results Our results showed that M2e-MAP vaccine induced strong M2e-specific IgG antibody responses following 3-dose immunization of mice with M2e-MAP in the presence of Freunds' or aluminium (alum adjuvant. M2e-MAP vaccination limited viral replication and attenuated histopathological damage in the challenged mouse lungs. The M2e-MAP-based vaccine protected immunized mice against both clade1: VN/1194 and clade2.3.4: SZ/406H H5N1 virus challenge, being able to counteract weight lost and elevate survival rate following lethal challenge of H5N1 viruses. Conclusions These results suggest that M2e-MAP presenting M2e of H5N1 virus has a great potential to be developed into an effective subunit vaccine for the prevention of infection by a broad spectrum of HPAI H5N1 viruses.

  14. Clinical differences between H3N2 and H1N1 influenza 2012 and lower respiratory tract infection found using a statistical classification approach

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    Petridis D

    2014-02-01

    Full Text Available Dimitris Petridis,1 Paul Zarogoulidis,2,3 Anastasios Kallianos,4 Ioannis Kioumis,2 Georgia Trakada,5 Dionysios Spyratos,2 Antonis Papaiwannou,2 Konstantinos Porpodis,2 Haidong Huang,6 Aggeliki Rapti,4 Wolfgang Hohenforst-Schmidt,7 Konstantinos Zarogoulidis2 1Department of Food Technology, Alexander Technological Educational Institute of Thessaloniki, Thessaloniki, Greece; 2Pulmonary Department, "G Papanikolaou" General Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece; 3Department of Interventional Pneumology, Ruhrlandklinik, West German Lung Center, University Hospital, University Duisburg-Essen, Essen, Germany; 42nd Pulmonary Department, "Sotiria" Hospital for Chest Diseases, Athens, Greece; 5Department of Clinical Therapeutics, Division of Pneumonology, Medical School, National University of Athens, Athens, Greece; 6Department of Respiratory Diseases, Changhai Hospital/First Affiliated Hospital of the Second Military Medical University, Shanghai, People's Republic of China; 7II Medical Department, "Coburg" Regional Clinic, University of Wüerzburg, Coburg, Germany Background: Influenza A H1N1 and H3N2 are two influenza waves that have been identified in past years. Methods: Data from 77 inpatients from three tertiary hospitals were included and statistical analysis was performed in three different clusters. Results: Thirty-four patients (44.2% had respiratory distress upon admission, 31.2% had a smoking history or were active smokers, 37.7% manifested disease symptoms, and 7.8% were obese (body mass index >41. The mean age of patients was 51.1 years. Cough was the most common symptom observed in 77.9% of the patients, accompanied by sputum production (51.9% and fatigue (42.9%. Hemoptysis and vomiting were rarely recorded in the patients (9.1% and 16.9%, respectively. Oseltamivir administration varied between 0 and 10 days, giving a mean value of 2.2 days. In particular, 19 patients received no drug, 31 patients received

  15. The transmissibility and control of pandemic influenza A (H1N1) virus.

    Science.gov (United States)

    Yang, Yang; Sugimoto, Jonathan D; Halloran, M Elizabeth; Basta, Nicole E; Chao, Dennis L; Matrajt, Laura; Potter, Gail; Kenah, Eben; Longini, Ira M

    2009-10-30

    Pandemic influenza A (H1N1) 2009 (pandemic H1N1) is spreading throughout the planet. It has become the dominant strain in the Southern Hemisphere, where the influenza season has now ended. Here, on the basis of reported case clusters in the United States, we estimated the household secondary attack rate for pandemic H1N1 to be 27.3% [95% confidence interval (CI) from 12.2% to 50.5%]. From a school outbreak, we estimated that a typical schoolchild infects 2.4 (95% CI from 1.8 to 3.2) other children within the school. We estimated the basic reproductive number, R0, to range from 1.3 to 1.7 and the generation interval to range from 2.6 to 3.2 days. We used a simulation model to evaluate the effectiveness of vaccination strategies in the United States for fall 2009. If a vaccine were available soon enough, vaccination of children, followed by adults, reaching 70% overall coverage, in addition to high-risk and essential workforce groups, could mitigate a severe epidemic.

  16. Pathobiology of highly pathogenic avian influenza virus (H5N1) infection in mute swans (Cygnus olor).

    Science.gov (United States)

    Pálmai, Nimród; Erdélyi, Károly; Bálint, Adám; Márton, Lázár; Dán, Adám; Deim, Zoltán; Ursu, Krisztina; Löndt, Brandon Z; Brown, Ian H; Glávits, Róbert

    2007-06-01

    The results of pathological, virological and polymerase chain reaction examinations carried out on 35 mute swans (Cygnus olor) that succumbed to a highly pathogenic avian influenza virus (H5N1) infection during an outbreak in Southern Hungary are reported. The most frequently observed macroscopic lesions included: haemorrhages under the epicardium, in the proventricular and duodenal mucosa and pancreas; focal necrosis in the pancreas; myocardial degeneration; acute mucous enteritis; congestion of the spleen and lung, and the accumulation of sero-mucinous exudate in the body cavity. Histopathological lesions comprised: lymphocytic meningo-encephalomyelitis accompanied by gliosis and occasional perivascular haemorrhages; multi-focal myocardial necrosis with lympho-histiocytic infiltration; pancreatitis with focal necrosis; acute desquamative mucous enteritis; lung congestion and oedema; oedema of the tracheal mucosa and, in young birds, the atrophy of the bursa of Fabricius as a result of lymphocyte depletion and apoptosis. The observed lesions and the moderate to good body conditions were compatible with findings in acute highly pathogenic avian influenza infections of other bird species reported in the literature. Skin lesions and lesions typical for infections caused by strains of lower pathogenicity (low pathogenic avian influenza virus) such as emaciation or fibrinous changes in the reproductive and respiratory organs, sinuses and airsacs were not observed. The H5N1 subtype avian influenza virus was isolated in embryonated fowl eggs from all cases and it was identified by classical and molecular virological methods.

  17. The chest X-ray manifestations of children with highly pathogenic H5N1 avian influenza virus infection (a report of 1 final diagnosis case and 1 borderline case)

    International Nuclear Information System (INIS)

    Jin Ke; Chen Hua; Tan Lihua; Yuan Youhong; Xiao Enhua; Luo Ruping; Li Wanging; Xu Heping

    2006-01-01

    Objective: To describe the chest X-ray manifestations of children with highly pathogenic H5N1 avian influenza virus infection. Methods: The pulmonary X-ray findings in 1 patient was confirmed by the World Health Organization infected H5N1 avian influenza vires and 1 borderline patient was retrospectively analyzed. Results: Both sides of lung field showed the cloudy and massive infiltration in chest X-ray film. The lesions of lung distributed extensively and symmetrically. Radiological dynamic changes showed the variation of the lesions of lung was quick in a short time. It had a characteristic of roving around. The lesions of lung appeared fibrosis at the period of the end. Conclusion: There are some radiographic characteristics in children with H5N1 avian influenza vires infection. It will be helpful for its diagnosis when getting familiar with its X-ray manifestations, but the final diagnosis is dependent on the epidemiology history and laboratory results. (authors)

  18. Protective Efficacy of Recombinant Turkey Herpes Virus (rHVT-H5) and Inactivated H5N1 Vaccines in Commercial Mulard Ducks against the Highly Pathogenic Avian Influenza (HPAI) H5N1 Clade 2.2.1 Virus.

    Science.gov (United States)

    Kilany, Walid H; Safwat, Marwa; Mohammed, Samy M; Salim, Abdullah; Fasina, Folorunso Oludayo; Fasanmi, Olubunmi G; Shalaby, Azhar G; Dauphin, Gwenaelle; Hassan, Mohammed K; Lubroth, Juan; Jobre, Yilma M

    2016-01-01

    In Egypt, ducks kept for commercial purposes constitute the second highest poultry population, at 150 million ducks/year. Hence, ducks play an important role in the introduction and transmission of avian influenza (AI) in the Egyptian poultry population. Attempts to control outbreaks include the use of vaccines, which have varying levels of efficacy and failure. To date, the effects of vaccine efficacy has rarely been determined in ducks. In this study, we evaluated the protective efficacy of a live recombinant vector vaccine based on a turkey Herpes Virus (HVT) expressing the H5 gene from a clade 2.2 H5N1 HPAIV strain (A/Swan/Hungary/499/2006) (rHVT-H5) and a bivalent inactivated H5N1 vaccine prepared from clade 2.2.1 and 2.2.1.1 H5N1 seeds in Mulard ducks. A 0.3ml/dose subcutaneous injection of rHVT-H5 vaccine was administered to one-day-old ducklings (D1) and another 0.5ml/dose subcutaneous injection of the inactivated MEFLUVAC was administered at 7 days (D7). Four separate challenge experiments were conducted at Days 21, 28, 35 and 42, in which all the vaccinated ducks were challenged with 106EID50/duck of H5N1 HPAI virus (A/chicken/Egypt/128s/2012(H5N1) (clade 2.2.1) via intranasal inoculation. Maternal-derived antibody regression and post-vaccination antibody immune responses were monitored weekly. Ducks vaccinated at 21, 28, 35 and 42 days with the rHVT-H5 and MEFLUVAC vaccines were protected against mortality (80%, 80%, 90% and 90%) and (50%, 70%, 80% and 90%) respectively, against challenges with the H5N1 HPAI virus. The amount of viral shedding and shedding rates were lower in the rHVT-H5 vaccine groups than in the MEFLUVAC groups only in the first two challenge experiments. However, the non-vaccinated groups shed significantly more of the virus than the vaccinated groups. Both rHVT-H5 and MEFLUVAC provide early protection, and rHVT-H5 vaccine in particular provides protection against HPAI challenge.

  19. Influenza A H1N1 pneumonia: radiograph and CT features of children

    International Nuclear Information System (INIS)

    Cheng Hua; Duan Xiaomin; Peng Yun; Zeng Jinjin; Sun Guoqiang

    2010-01-01

    Objective: To explore the imaging features on chest radiograph and CT in children with Influenza A H1N1 pneumonia. Methods: The imaging data of chest radiograph and CT in six children with Influenza A H1N1 pneumonia confirmed by real-time RT-PCR assay was retrospectively analysis. All patients had chest radiograph at first examination and 4 of them re-examed. One children took CT. Results: All cases showed thick lung markings with varied degrees of pulmonary infiltration and interstitial changes on chest radiograph. Among them, 3 cases showed bilateral pulmonary infiltration and 3 cases showed infiltration in left lung; enlarged hilar was observed in 3 cases. The imaging findings of the pneumonia changed quickly during the follow-up accompanied with the improvement of clinical symptoms. The only one chest CT examination showed bilateral infiltration, multiple ground-glass opacities, small subpleural nodulars, right pleural effusion and lymphadenopathy of lung hila and mediastinum. Conclusions: Chest radiograph and CT revealed certain typical imaging features in the children with influenza A H1N1 pneumonia. However, the final diagnosis of influenza A H1N1 pneumonia still should be made based on epidemiology and laboratory examination. (authors)

  20. The impact of the pandemic influenza A(H1N1) 2009 virus on seasonal influenza A viruses in the southern hemisphere, 2009.

    Science.gov (United States)

    Blyth, C C; Kelso, A; McPhie, K A; Ratnamohan, V M; Catton, M; Druce, J D; Smith, D W; Williams, S H; Huang, Q S; Lopez, L; Schoub, B D; Venter, M; Dwyer, D E

    2010-08-05

    Data collected over winter 2009 by five World Health Organisation National Influenza Centres in the southern hemisphere were used to examine the circulation of pandemic and seasonal influenza A strains during the first pandemic wave in the southern hemisphere.There is compelling evidence that the pandemic influenza A(H1N1) 2009 virus significantly displaced seasonal influenza A(H1N1) and, to a lesser extent, A(H3N2) viruses circulating in the southern hemisphere. Complete replacement of seasonal influenza A strains, however, was not observed during the first pandemic wave.

  1. Conservation and diversity of influenza A H1N1 HLA-restricted T cell epitope candidates for epitope-based vaccines.

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    Paul Thiamjoo Tan

    2010-01-01

    Full Text Available The immune-related evolution of influenza viruses is exceedingly complex and current vaccines against influenza must be reformulated for each influenza season because of the high degree of antigenic drift among circulating influenza strains. Delay in vaccine production is a serious problem in responding to a pandemic situation, such as that of the current H1N1 strain. Immune escape is generally attributed to reduced antibody recognition of the viral hemagglutinin and neuraminidase proteins whose rate of mutation is much greater than that of the internal non-structural proteins. As a possible alternative, vaccines directed at T cell epitope domains of internal influenza proteins, that are less susceptible to antigenic variation, have been investigated.HLA transgenic mouse strains expressing HLA class I A*0201, A*2402, and B*0702, and class II DRB1*1501, DRB1*0301 and DRB1*0401 were immunized with 196 influenza H1N1 peptides that contained residues of highly conserved proteome sequences of the human H1N1, H3N2, H1N2, H5N1, and avian influenza A strains. Fifty-four (54 peptides that elicited 63 HLA-restricted peptide-specific T cell epitope responses were identified by IFN-gamma ELISpot assay. The 54 peptides were compared to the 2007-2009 human H1N1 sequences for selection of sequences in the design of a new candidate H1N1 vaccine, specifically targeted to highly-conserved HLA-restricted T cell epitopes.Seventeen (17 T cell epitopes in PB1, PB2, and M1 were selected as vaccine targets based on sequence conservation over the past 30 years, high functional avidity, non-identity to human peptides, clustered localization, and promiscuity to multiple HLA alleles. These candidate vaccine antigen sequences may be applicable to any avian or human influenza A virus.

  2. Swine Influenza Virus (H1N2) Characterization and Transmission in Ferrets, Chile.

    Science.gov (United States)

    Bravo-Vasquez, Nicolás; Karlsson, Erik A; Jimenez-Bluhm, Pedro; Meliopoulos, Victoria; Kaplan, Bryan; Marvin, Shauna; Cortez, Valerie; Freiden, Pamela; Beck, Melinda A; Hamilton-West, Christopher; Schultz-Cherry, Stacey

    2017-02-01

    Phylogenetic analysis of the influenza hemagglutinin gene (HA) has suggested that commercial pigs in Chile harbor unique human seasonal H1-like influenza viruses, but further information, including characterization of these viruses, was unavailable. We isolated influenza virus (H1N2) from a swine in a backyard production farm in Central Chile and demonstrated that the HA gene was identical to that in a previous report. Its HA and neuraminidase genes were most similar to human H1 and N2 viruses from the early 1990s and internal segments were similar to influenza A(H1N1)pdm09 virus. The virus replicated efficiently in vitro and in vivo and transmitted in ferrets by respiratory droplet. Antigenically, it was distinct from other swine viruses. Hemagglutination inhibition analysis suggested that antibody titers to the swine Chilean H1N2 virus were decreased in persons born after 1990. Further studies are needed to characterize the potential risk to humans, as well as the ecology of influenza in swine in South America.

  3. Isolation of avian influenza H5N1 virus from vaccinated commercial layer flock in Egypt

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    El-Zoghby Elham F

    2012-11-01

    Full Text Available Abstract Background Uninterrupted transmission of highly pathogenic avian influenza virus (HPAIV H5N1 of clade 2.2.1 in Egypt since 2006 resulted in establishment of two main genetic clusters. The 2.2.1/C group where all recent human and majority of backyard origin viruses clustered together, meanwhile the majority of viruses derived from vaccinated poultry in commercial farms grouped in 2.2.1.1 clade. Findings In the present investigation, an HPAIV H5N1 was isolated from twenty weeks old layers chickens that were vaccinated with a homologous H5N1 vaccine at 1, 7 and 16 weeks old. At twenty weeks of age, birds showed cyanosis of comb and wattle, decrease in egg production and up to 27% mortality. Examined serum samples showed low antibody titer in HI test (Log2 3.2± 4.2. The hemagglutinin (HA and neuraminidase (NA genes of the isolated virus were closely related to viruses in 2.2.1/C group isolated from poultry in live bird market (LBM and backyards or from infected people. Conspicuous mutations in the HA and NA genes including a deletion within the receptor binding domain in the HA globular head region were observed. Conclusions Despite repeated vaccination of layer chickens using a homologous H5N1 vaccine, infection with HPAIV H5N1 resulted in significant morbidity and mortality. In endemic countries like Egypt, rigorous control measures including enforcement of biosecurity, culling of infected birds and constant update of vaccine virus strains are highly required to prevent circulation of HPAIV H5N1 between backyard birds, commercial poultry, LBM and humans.

  4. Screening for Influenza A(H1N1)pdm09, Auckland International Airport, New Zealand

    Science.gov (United States)

    Hale, Michael J.; Baker, Michael G.

    2012-01-01

    Entry screening for influenza A(H1N1)pdm09 at Auckland International Airport, New Zealand, detected 4 cases, which were later confirmed, among 456,518 passengers arriving April 27–June 22, 2009. On the basis of national influenza surveillance data, which suggest that ≈69 infected travelers passed through the airport, sensitivity for screening was only 5.8%. PMID:22516105

  5. Experimental infection of highly pathogenic avian influenza virus H5N1 in black-headed gulls (Chroicocephalus ridibundus)

    NARCIS (Netherlands)

    A. Ramis (Antonio); G. van Amerongen (Geert); M.W.G. van de Bildt (Marco); L.M.E. Leijten (Lonneke); R. Vanderstichel (R.); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

    2014-01-01

    textabstractHistorically, highly pathogenic avian influenza viruses (HPAIV) rarely resulted in infection or clinical disease in wild birds. However, since 2002, disease and mortality from natural HPAIV H5N1 infection have been observed in wild birds including gulls. We performed an experimental

  6. Indium-tin-oxide thin film transistor biosensors for label-free detection of avian influenza virus H5N1

    Energy Technology Data Exchange (ETDEWEB)

    Guo, Di; Zhuo, Ming [Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Zhang, Xiaoai [State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing (China); Xu, Cheng; Jiang, Jie [Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Gao, Fu [State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing (China); Wan, Qing, E-mail: wanqing7686@hotmail.com [Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Li, Qiuhong, E-mail: liqiuhong2004@hotmail.com [Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China); Wang, Taihong, E-mail: thwang@hnu.cn [Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, State Key Laboratory for Chemo/Biosensing and Chemometrics, Hunan University, Changsha 410082 (China)

    2013-04-22

    Highlights: ► A highly selective label-free biosensor is established based on indium-tin-oxide thin-film transistors (ITO TFTs). ► AI H5N1 virus was successfully detected through shift in threshold voltage and field-effect mobility of ITO TFT. ► The ITO TFT is applied in biosensor for the first time and shows good reusability and stability. ► Fabrication of the platform is simple with low cost, which is suitable for mass commercial production. -- Abstract: As continuous outbreak of avian influenza (AI) has become a threat to human health, economic development and social stability, it is urgently necessary to detect the highly pathogenic avian influenza H5N1 virus quickly. In this study, we fabricated indium-tin-oxide thin-film transistors (ITO TFTs) on a glass substrate for the detecting of AI H5N1. The ITO TFT is fabricated by a one-shadow-mask process in which a channel layer can be simultaneously self-assembled between ITO source/drain electrodes during magnetron sputtering deposition. Monoclonal anti-H5N1 antibodies specific for AI H5N1 virus were covalently immobilized on the ITO channel by (3-glycidoxypropyl)trimethoxysilane. The introduction of target AI H5N1 virus affected the electronic properties of the ITO TFT, which caused a change in the resultant threshold voltage (V{sub T}) and field-effect mobility. The changes of I{sub D}–V{sub G} curves were consistent with an n-type field effect transistor behavior affected by nearby negatively charged AI H5N1 viruses. The transistor based sensor demonstrated high selectivity and stability for AI H5N1 virus sensing. The sensor showed linear response to AI H5N1 in the concentrations range from 5 × 10{sup −9} g mL{sup −1} to 5 × 10{sup −6} g mL{sup −1} with a detection limit of 0.8 × 10{sup −10} g mL{sup −1}. Moreover, the ITO TFT biosensors can be repeatedly used through the washing processes. With its excellent electric properties and the potential for mass commercial production, ITO TFTs

  7. Seroprevalence of H1N1, H3N2 and H1N2 influenza viruses in pigs in seven European countries in 2002-2003

    NARCIS (Netherlands)

    Reeth, K.; Brown, I.H.; Durrwald, R.; Foni, E.; Labarque, G.; Lenihan, P.; Maldonado, J.; Markowska-Daniel, I.; Pensaert, M.; Pospisil, Z.; Koch, G.

    2008-01-01

    Objectives Avian-like H1N1 and human-like H3N2 swine influenza viruses (SIV) have been considered widespread among pigs in Western Europe since the 1980s, and a novel H1N2 reassortant with a human-like H1 emerged in the mid 1990s. This study, which was part of the EC-funded 'European Surveillance

  8. Clinical characteristics of acute encephalopathies associated with influenza H1N1-2009 in children

    International Nuclear Information System (INIS)

    Watanabe, Yashihiro; Tsuji, Megumi; Sameshima, Kiyoko; Wada, Takahito; Iai, Mizue; Yamashita, Sumimasa; Hayashi, Takuya; Aida, Noriko; Osaka, Hiroshi

    2012-01-01

    We report 12 cases of acute encephalopathy associated with influenza H1N1-2009 treated according to Japanese guideline (2009). In all 12 cases, electroencephalogram presented diffuse or localized high-amplitude slow waves. Brain CT and MRI showed abnormalities in 4 and 6 cases, respectively. We used hypothermia therapy for 5 patients. One patient showed impairment in short term memory, while the rest of the patients showed no sequelae. These 12 cases presented here suggest the early recognition and therapy according to the newly proposed guideline may reduce severe sequelae and mortality by acute encephalopathy associated with influenza H1N1-2009. (author)

  9. Experimentally infected domestic ducks show efficient transmission of Indonesian H5N1 highly pathogenic avian influenza virus, but lack persistent viral shedding.

    Science.gov (United States)

    Wibawa, Hendra; Bingham, John; Nuradji, Harimurti; Lowther, Sue; Payne, Jean; Harper, Jenni; Junaidi, Akhmad; Middleton, Deborah; Meers, Joanne

    2014-01-01

    Ducks are important maintenance hosts for avian influenza, including H5N1 highly pathogenic avian influenza viruses. A previous study indicated that persistence of H5N1 viruses in ducks after the development of humoral immunity may drive viral evolution following immune selection. As H5N1 HPAI is endemic in Indonesia, this mechanism may be important in understanding H5N1 evolution in that region. To determine the capability of domestic ducks to maintain prolonged shedding of Indonesian clade 2.1 H5N1 virus, two groups of Pekin ducks were inoculated through the eyes, nostrils and oropharynx and viral shedding and transmission investigated. Inoculated ducks (n = 15), which were mostly asymptomatic, shed infectious virus from the oral route from 1 to 8 days post inoculation, and from the cloacal route from 2-8 dpi. Viral ribonucleic acid was detected from 1-15 days post inoculation from the oral route and 1-24 days post inoculation from the cloacal route (cycle threshold ducks seroconverted in a range of serological tests by 15 days post inoculation. Virus was efficiently transmitted during acute infection (5 inoculation-infected to all 5 contact ducks). However, no evidence for transmission, as determined by seroconversion and viral shedding, was found between an inoculation-infected group (n = 10) and contact ducks (n = 9) when the two groups only had contact after 10 days post inoculation. Clinical disease was more frequent and more severe in contact-infected (2 of 5) than inoculation-infected ducks (1 of 15). We conclude that Indonesian clade 2.1 H5N1 highly pathogenic avian influenza virus does not persist in individual ducks after acute infection.

  10. Adaptation of Pandemic H1N1 Influenza Viruses in Mice▿

    Science.gov (United States)

    Ilyushina, Natalia A.; Khalenkov, Alexey M.; Seiler, Jon P.; Forrest, Heather L.; Bovin, Nicolai V.; Marjuki, Henju; Barman, Subrata; Webster, Robert G.; Webby, Richard J.

    2010-01-01

    The molecular mechanism by which pandemic 2009 influenza A viruses were able to sufficiently adapt to humans is largely unknown. Subsequent human infections with novel H1N1 influenza viruses prompted an investigation of the molecular determinants of the host range and pathogenicity of pandemic influenza viruses in mammals. To address this problem, we assessed the genetic basis for increased virulence of A/CA/04/09 (H1N1) and A/TN/1-560/09 (H1N1) isolates, which are not lethal for mice, in a new mammalian host by promoting their mouse adaptation. The resulting mouse lung-adapted variants showed significantly enhanced growth characteristics in eggs, extended extrapulmonary tissue tropism, and pathogenicity in mice. All mouse-adapted viruses except A/TN/1-560/09-MA2 grew faster and to higher titers in cells than the original strains. We found that 10 amino acid changes in the ribonucleoprotein (RNP) complex (PB2 E158G/A, PA L295P, NP D101G, and NP H289Y) and hemagglutinin (HA) glycoprotein (K119N, G155E, S183P, R221K, and D222G) controlled enhanced mouse virulence of pandemic isolates. HA mutations acquired during adaptation affected viral receptor specificity by enhancing binding to α2,3 together with decreasing binding to α2,6 sialyl receptors. PB2 E158G/A and PA L295P amino acid substitutions were responsible for the significant enhancement of transcription and replication activity of the mouse-adapted H1N1 variants. Taken together, our findings suggest that changes optimizing receptor specificity and interaction of viral polymerase components with host cellular factors are the major mechanisms that contribute to the optimal competitive advantage of pandemic influenza viruses in mice. These modulators of virulence, therefore, may have been the driving components of early evolution, which paved the way for novel 2009 viruses in mammals. PMID:20592084

  11. Effect of priming with H1N1 influenza viruses of variable antigenic distances on challenge with 2009 pandemic H1N1 virus.

    Science.gov (United States)

    O'Donnell, Christopher D; Wright, Amber; Vogel, Leatrice N; Wei, Chih-Jen; Nabel, Gary J; Subbarao, Kanta

    2012-08-01

    Compared to seasonal influenza viruses, the 2009 pandemic H1N1 (pH1N1) virus caused greater morbidity and mortality in children and young adults. People over 60 years of age showed a higher prevalence of cross-reactive pH1N1 antibodies, suggesting that they were previously exposed to an influenza virus or vaccine that was antigenically related to the pH1N1 virus. To define the basis for this cross-reactivity, ferrets were infected with H1N1 viruses of variable antigenic distance that circulated during different decades from the 1930s (Alaska/35), 1940s (Fort Monmouth/47), 1950s (Fort Warren/50), and 1990s (New Caledonia/99) and challenged with 2009 pH1N1 virus 6 weeks later. Ferrets primed with the homologous CA/09 or New Jersey/76 (NJ/76) virus served as a positive control, while the negative control was an influenza B virus that should not cross-protect against influenza A virus infection. Significant protection against challenge virus replication in the respiratory tract was observed in ferrets primed with AK/35, FM/47, and NJ/76; FW/50-primed ferrets showed reduced protection, and NC/99-primed ferrets were not protected. The hemagglutinins (HAs) of AK/35, FM/47, and FW/50 differ in the presence of glycosylation sites. We found that the loss of protective efficacy observed with FW/50 was associated with the presence of a specific glycosylation site. Our results suggest that changes in the HA occurred between 1947 and 1950, such that prior infection could no longer protect against 2009 pH1N1 infection. This provides a mechanistic understanding of the nature of serological cross-protection observed in people over 60 years of age during the 2009 H1N1 pandemic.

  12. Underreporting of 2009 H1N1 Influenza Cases

    Centers for Disease Control (CDC) Podcasts

    2009-12-08

    Influenza cases are difficult to track because many people don't go to the doctor or get tested for flu when they're sick. The first months of the 2009 H1N1 influenza pandemic were no different. In this podcast, CDC's Dr. Carrie Reed discusses a study in the December issue of Emerging Infectious Diseases that looked at the actual number of cases reported and estimated the true number of cases when correcting for underreporting.  Created: 12/8/2009 by Emerging Infectious Diseases.   Date Released: 12/8/2009.

  13. Avian influenza H5N1 transmission in households, Indonesia.

    Directory of Open Access Journals (Sweden)

    Tjandra Y Aditama

    Full Text Available BACKGROUND: Disease transmission patterns are needed to inform public health interventions, but remain largely unknown for avian influenza H5N1 virus infections. A recent study on the 139 outbreaks detected in Indonesia between 2005 and 2009 found that the type of exposure to sources of H5N1 virus for both the index case and their household members impacted the risk of additional cases in the household. This study describes the disease transmission patterns in those outbreak households. METHODOLOGY/PRINCIPAL FINDINGS: We compared cases (n = 177 and contacts (n = 496 in the 113 sporadic and 26 cluster outbreaks detected between July 2005 and July 2009 to estimate attack rates and disease intervals. We used final size household models to fit transmission parameters to data on household size, cases and blood-related household contacts to assess the relative contribution of zoonotic and human-to-human transmission of the virus, as well as the reproduction number for human virus transmission. The overall household attack rate was 18.3% and secondary attack rate was 5.5%. Secondary attack rate remained stable as household size increased. The mean interval between onset of subsequent cases in outbreaks was 5.6 days. The transmission model found that human transmission was very rare, with a reproduction number between 0.1 and 0.25, and the upper confidence bounds below 0.4. Transmission model fit was best when the denominator population was restricted to blood-related household contacts of index cases. CONCLUSIONS/SIGNIFICANCE: The study only found strong support for human transmission of the virus when a single large cluster was included in the transmission model. The reproduction number was well below the threshold for sustained transmission. This study provides baseline information on the transmission dynamics for the current zoonotic virus and can be used to detect and define signatures of a virus with increasing capacity for human

  14. Chalcones as novel influenza A (H1N1) neuraminidase inhibitors from Glycyrrhiza inflata

    DEFF Research Database (Denmark)

    Dao, Trong Tuan; Nguyen, Phi Hung; Lee, Hong Sik

    2011-01-01

    The emergence of highly pathogenic influenza A virus strains, such as the new H1N1 swine influenza (novel influenza), represents a serious threat to global human health. During our course of an anti-influenza screening program on natural products, one new licochalcone G (1) and seven known (2-8) ...

  15. In vitro assessment of attachment pattern and replication efficiency of H5N1 influenza A viruses with altered receptor specificity

    NARCIS (Netherlands)

    S. Chutinimitkul (Salin); D.A.J. van Riel (Debby); V.J. Munster (Vincent); J.M.A. van den Brand (Judith); G.F. Rimmelzwaan (Guus); T. Kuiken (Thijs); A.D.M.E. Osterhaus (Albert); R.A.M. Fouchier (Ron); E. de Wit (Emmie)

    2010-01-01

    textabstractThe continuous circulation of the highly pathogenic avian influenza (HPAI) H5N1 virus has been a cause of great concern. The possibility of this virus acquiring specificity for the human influenza A virus receptor, α2,6-linked sialic acids (SA), and being able to transmit efficiently

  16. Novel H7N2 and H5N6 Avian Influenza A Viruses in Sentinel Chickens: A Sentinel Chicken Surveillance Study

    Directory of Open Access Journals (Sweden)

    Teng Zhao

    2016-11-01

    Full Text Available In 2014, surveillance of sentinel chicken for avian influenza virus was conducted in aquatic bird habitat near Wuxi City, Jiangsu Province, China. Two H7N2, one H5N6, and two H9N2 viruses were isolated. Sequence analysis revealed that the H7N2 virus is a novel reassortant of H7N9 and H9N2 viruses and H5N6 virus is a reassortant of H5N1 clade 2.3.4 and H6N6 viruses. Substitutions V186 and L226 (H3 numbering in the hemagglutinin (HA gene protein was found in two H7N2 viruses but not in the H5N6 virus. Two A138 and A160 mutations were identified in the HA gene protein of all three viruses but a P128 mutation was only in the H5N6 virus. A deletion of three and eleven amino acids in the neuraminidase stalk region was found in two H7N2 and H5N6 viruses, respectively. Moreover, a mutation of N31 in M2 protein was observed in both two H7N2 viruses. High similarity of these isolated viruses to viruses previously identified among poultry and humans, suggests that peridomestic aquatic birds may play a role in sustaining novel virus transmission. Therefore, continued surveillance is needed to monitor these avian influenza viruses in wild bird and domestic poultry that may pose a threat to poultry and human health.

  17. Efficacy of two H5N9-inactivated vaccines against challenge with a recent H5N1 highly pathogenic avian influenza isolate from a chicken in Thailand.

    Science.gov (United States)

    Bublot, Michel; Le Gros, François-Xavier; Nieddu, Daniela; Pritchard, Nikki; Mickle, Thomas R; Swayne, David E

    2007-03-01

    The objective of this study was to compare the efficacy of two avian influenza (AI) H5-inactivated vaccines containing either an American (A/turkey/Wisconsin/68 H5N9; H5N9-WI) or a Eurasian isolate (A/chicken/Italy/22A/98 H5N9; H5N9-It). Three-week-old specific pathogen-free chickens were vaccinated once and challenged 3 wk later with a H5N1 highly pathogenic AI (HPAI) virus isolated from a chicken in Thailand in 2004. All unvaccinated challenged birds died within 2 days, whereas 90% and 100% of chickens vaccinated with H5N9-WI and H5N9-It, respectively, were protected against morbidity and mortality. Both vaccines prevented cloacal shedding and significantly reduced oral shedding of the challenge HPAI virus. Additional chickens (vaccinated or unvaccinated) were placed in contact with the directly challenged birds 18 hr after challenge. All unvaccinated chickens in contact with unvaccinated challenged birds died within 3 days after contact, whereas unvaccinated chickens in contact with vaccinated challenged birds either showed a significantly delayed mortality or did not become infected. All vaccinated contacts were protected against clinical signs, and most chickens did not shed detectable amount of HPAI virus. Altogether, these data indicate that both vaccines protected very well against morbidity and mortality and reduced or prevented shedding induced by direct or contact exposure to Asian H5N1 HPAI virus.

  18. Seroprevalence of antibodies against highly pathogenic avian influenza A (H5N1 virus among poultry workers in Bangladesh, 2009.

    Directory of Open Access Journals (Sweden)

    Sharifa Nasreen

    Full Text Available We conducted a cross-sectional study in 2009 to determine the seroprevalence and risk factors for highly pathogenic avian influenza A (H5N1 [HPAI H5N1] virus antibodies among poultry workers at farms and live bird markets with confirmed/suspected poultry outbreaks during 2009 in Bangladesh. We tested sera by microneutralization assay using A/Bangladesh/207095/2008 (H5N1; clade 2.2.2 virus with confirmation by horse red blood cell hemagglutination inhibition and H5-specific Western blot assays. We enrolled 212 workers from 87 farms and 210 workers from three live bird markets. One hundred and two farm workers (48% culled poultry. One hundred and ninety-three farm workers (91% and 178 market workers (85% reported direct contact with poultry that died during a laboratory confirmed HPAI H5N1 poultry farm outbreak or market poultry die-offs from suspected HPAI H5N1. Despite exposure to sick poultry, no farm or market poultry workers were seropositive for HPAI H5N1 virus antibodies (95% confidence interval 0-1%.

  19. Development and implementation of the quality control panel of RT-PCR and real-time RT-PCR for avian influenza A (H5N1 surveillance network in mainland China

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2011-03-01

    Full Text Available Abstract Background Reverse transcription PCR (RT-PCR and real time RT-PCR (rRT-PCR have been indispensable methods for influenza surveillance, especially for determination of avian influenza. The movement of testing beyond reference lab introduced the need of quality control, including the implementation of an evaluation system for validating personal training and sample proficiency testing. Methods We developed a panel with lysates of seasonal influenza virus (H1N1, H3N2 and B, serials of diluted H5N1 virus lysates, and in-vitro transcribed H5 hemaglutinin (HA and an artificial gene RNAs for RT-PCR and rRT-PCR quality control assessment. The validations of stability and reproducibility were performed on the panel. Additionally, the panel was implemented to assess the detection capability of Chinese human avian influenza networks. Results The panel has relatively high stability and good reproducibility demonstrated by kappa's tests. In the implementation of panel on Chinese human avian influenza networks, the results suggested that there were a relatively low number of discrepancies for both concise and reproducibility in Chinese avian influenza virus net works. Conclusions A quality control panel of RT-PCR and real-time RT-PCR for avian influenza A (H5N1 surveillance network was developed. An availably statistical data, which are used to assess the detection capability of networks on avian influenza virus (H5N1, can be obtained relatively easily through implementation of the panel on networks.

  20. Influenza A H5N1 clade 2.3.4 virus with a different antiviral susceptibility profile replaced clade 1 virus in humans in northern Vietnam

    NARCIS (Netherlands)

    Le, Mai T. Q.; Wertheim, Heiman F. L.; Nguyen, Hien D.; Taylor, Walter; Hoang, Phuong V. M.; Vuong, Cuong D.; Nguyen, Hang L. K.; Nguyen, Ha H.; Nguyen, Thai Q.; Nguyen, Trung V.; van, Trang D.; Ngoc, Bich T.; Bui, Thinh N.; Nguyen, Binh G.; Nguyen, Liem T.; Luong, San T.; Phan, Phuc H.; Pham, Hung V.; Nguyen, Tung; Fox, Annette; Nguyen, Cam V.; Do, Ha Q.; Crusat, Martin; Farrar, Jeremy; Nguyen, Hien T.; de Jong, Menno D.; Horby, Peter

    2008-01-01

    BACKGROUND: Prior to 2007, highly pathogenic avian influenza (HPAI) H5N1 viruses isolated from poultry and humans in Vietnam were consistently reported to be clade 1 viruses, susceptible to oseltamivir but resistant to amantadine. Here we describe the re-emergence of human HPAI H5N1 virus infections

  1. Effect of neuraminidase inhibitor-resistant mutations on pathogenicity of clade 2.2 A/Turkey/15/06 (H5N1) influenza virus in ferrets.

    Science.gov (United States)

    Ilyushina, Natalia A; Seiler, Jon P; Rehg, Jerold E; Webster, Robert G; Govorkova, Elena A

    2010-05-27

    The acquisition of neuraminidase (NA) inhibitor resistance by H5N1 influenza viruses has serious clinical implications, as this class of drugs can be an essential component of pandemic control measures. The continuous evolution of the highly pathogenic H5N1 influenza viruses results in the emergence of natural NA gene variations whose impact on viral fitness and NA inhibitor susceptibility are poorly defined. We generated seven genetically stable recombinant clade 2.2 A/Turkey/15/06-like (H5N1) influenza viruses carrying NA mutations located either in the framework residues (E119A, H274Y, N294S) or in close proximity to the NA enzyme active site (V116A, I117V, K150N, Y252H). NA enzyme inhibition assays showed that NA mutations at positions 116, 117, 274, and 294 reduced susceptibility to oseltamivir carboxylate (IC(50)s increased 5- to 940-fold). Importantly, the E119A NA mutation (previously reported to confer resistance in the N2 NA subtype) was stable in the clade 2.2 H5N1 virus background and induced cross-resistance to oseltamivir carboxylate and zanamivir. We demonstrated that Y252H NA mutation contributed for decreased susceptibility of clade 2.2 H5N1 viruses to oseltamivir carboxylate as compared to clade 1 viruses. The enzyme kinetic parameters (V(max), K(m) and K(i)) of the avian-like N1 NA glycoproteins were highly consistent with their IC(50) values. None of the recombinant H5N1 viruses had attenuated virulence in ferrets inoculated with 10(6) EID(50) dose. Most infected ferrets showed mild clinical disease signs that differed in duration. However, H5N1 viruses carrying the E119A or the N294S NA mutation were lethal to 1 of 3 inoculated animals and were associated with significantly higher virus titers (Pinfluenza drugs that target different virus/host factors and can limit the emergence of resistance.

  2. Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species

    Science.gov (United States)

    Hall, Jeffrey S.; Franson, J. Christian; Gill, Robert E.; Meteyer, Carol U.; TeSlaa, Joshua L.; Nashold, Sean W.; Dusek, Robert J.; Ip, Hon S.

    2011-01-01

    Background Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds.

  3. Spatial distribution and risk factors of highly pathogenic avian influenza (HPAI) H5N1 in China

    Science.gov (United States)

    Martin, Vincent; Pfeiffer, Dirk U.; Zhou, Xiaoyan; Xiao, Xiangming; Prosser, Diann J.; Guo, Fusheng; Gilbert, Marius

    2011-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 was first encountered in 1996 in Guangdong province (China) and started spreading throughout Asia and the western Palearctic in 2004–2006. Compared to several other countries where the HPAI H5N1 distribution has been studied in some detail, little is known about the environmental correlates of the HPAI H5N1 distribution in China. HPAI H5N1 clinical disease outbreaks, and HPAI virus (HPAIV) H5N1 isolated from active risk-based surveillance sampling of domestic poultry (referred to as HPAIV H5N1 surveillance positives in this manuscript) were modeled separately using seven risk variables: chicken, domestic waterfowl population density, proportion of land covered by rice or surface water, cropping intensity, elevation, and human population density. We used bootstrapped logistic regression and boosted regression trees (BRT) with cross-validation to identify the weight of each variable, to assess the predictive power of the models, and to map the distribution of HPAI H5N1 risk. HPAI H5N1 clinical disease outbreak occurrence in domestic poultry was mainly associated with chicken density, human population density, and elevation. In contrast, HPAIV H5N1 infection identified by risk-based surveillance was associated with domestic waterfowl density, human population density, and the proportion of land covered by surface water. Both models had a high explanatory power (mean AUC ranging from 0.864 to 0.967). The map of HPAIV H5N1 risk distribution based on active surveillance data emphasized areas south of the Yangtze River, while the distribution of reported outbreak risk extended further North, where the density of poultry and humans is higher. We quantified the statistical association between HPAI H5N1 outbreak, HPAIV distribution and post-vaccination levels of seropositivity (percentage of effective post-vaccination seroconversion in vaccinated birds) and found that provinces with either outbreaks or HPAIV H5N1 surveillance

  4. Spatial distribution and risk factors of highly pathogenic avian influenza (HPAI H5N1 in China.

    Directory of Open Access Journals (Sweden)

    Vincent Martin

    2011-03-01

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 was first encountered in 1996 in Guangdong province (China and started spreading throughout Asia and the western Palearctic in 2004-2006. Compared to several other countries where the HPAI H5N1 distribution has been studied in some detail, little is known about the environmental correlates of the HPAI H5N1 distribution in China. HPAI H5N1 clinical disease outbreaks, and HPAI virus (HPAIV H5N1 isolated from active risk-based surveillance sampling of domestic poultry (referred to as HPAIV H5N1 surveillance positives in this manuscript were modeled separately using seven risk variables: chicken, domestic waterfowl population density, proportion of land covered by rice or surface water, cropping intensity, elevation, and human population density. We used bootstrapped logistic regression and boosted regression trees (BRT with cross-validation to identify the weight of each variable, to assess the predictive power of the models, and to map the distribution of HPAI H5N1 risk. HPAI H5N1 clinical disease outbreak occurrence in domestic poultry was mainly associated with chicken density, human population density, and elevation. In contrast, HPAIV H5N1 infection identified by risk-based surveillance was associated with domestic waterfowl density, human population density, and the proportion of land covered by surface water. Both models had a high explanatory power (mean AUC ranging from 0.864 to 0.967. The map of HPAIV H5N1 risk distribution based on active surveillance data emphasized areas south of the Yangtze River, while the distribution of reported outbreak risk extended further North, where the density of poultry and humans is higher. We quantified the statistical association between HPAI H5N1 outbreak, HPAIV distribution and post-vaccination levels of seropositivity (percentage of effective post-vaccination seroconversion in vaccinated birds and found that provinces with either outbreaks or HPAIV H5N1

  5. A host transcriptional signature for presymptomatic detection of infection in humans exposed to influenza H1N1 or H3N2.

    Directory of Open Access Journals (Sweden)

    Christopher W Woods

    Full Text Available There is great potential for host-based gene expression analysis to impact the early diagnosis of infectious diseases. In particular, the influenza pandemic of 2009 highlighted the challenges and limitations of traditional pathogen-based testing for suspected upper respiratory viral infection. We inoculated human volunteers with either influenza A (A/Brisbane/59/2007 (H1N1 or A/Wisconsin/67/2005 (H3N2, and assayed the peripheral blood transcriptome every 8 hours for 7 days. Of 41 inoculated volunteers, 18 (44% developed symptomatic infection. Using unbiased sparse latent factor regression analysis, we generated a gene signature (or factor for symptomatic influenza capable of detecting 94% of infected cases. This gene signature is detectable as early as 29 hours post-exposure and achieves maximal accuracy on average 43 hours (p = 0.003, H1N1 and 38 hours (p-value = 0.005, H3N2 before peak clinical symptoms. In order to test the relevance of these findings in naturally acquired disease, a composite influenza A signature built from these challenge studies was applied to Emergency Department patients where it discriminates between swine-origin influenza A/H1N1 (2009 infected and non-infected individuals with 92% accuracy. The host genomic response to Influenza infection is robust and may provide the means for detection before typical clinical symptoms are apparent.

  6. Calculating the potential for within-flight transmission of influenza A (H1N1

    Directory of Open Access Journals (Sweden)

    Blower Sally

    2009-12-01

    Full Text Available Abstract Background Clearly air travel, by transporting infectious individuals from one geographic location to another, significantly affects the rate of spread of influenza A (H1N1. However, the possibility of within-flight transmission of H1N1 has not been evaluated; although it is known that smallpox, measles, tuberculosis, SARS and seasonal influenza can be transmitted during commercial flights. Here we present the first quantitative risk assessment to assess the potential for within-flight transmission of H1N1. Methods We model airborne transmission of infectious viral particles of H1N1 within a Boeing 747 using methodology from the field of quantitative microbial risk assessment. Results The risk of catching H1N1 will essentially be confined to passengers travelling in the same cabin as the source case. Not surprisingly, we find that the longer the flight the greater the number of infections that can be expected. We calculate that H1N1, even during long flights, poses a low to moderate within-flight transmission risk if the source case travels First Class. Specifically, 0-1 infections could occur during a 5 hour flight, 1-3 during an 11 hour flight and 2-5 during a 17 hour flight. However, within-flight transmission could be significant, particularly during long flights, if the source case travels in Economy Class. Specifically, two to five infections could occur during a 5 hour flight, 5-10 during an 11 hour flight and 7-17 during a 17 hour flight. If the aircraft is only partially loaded, under certain conditions more infections could occur in First Class than in Economy Class. During a 17 hour flight, a greater number of infections would occur in First Class than in Economy if the First Class Cabin is fully occupied, but Economy class is less than 30% full. Conclusions Our results provide insights into the potential utility of air travel restrictions on controlling influenza pandemics in the winter of 2009/2010. They show travel by one

  7. MERS-CoV and H5N1 influenza virus antagonize antigen presentation by altering the epigenetic landscape

    Energy Technology Data Exchange (ETDEWEB)

    Menachery, Vineet D.; Schafer, Alexandra; Burnum-Johnson, Kristin E.; Mitchell, Hugh D.; Eisfeld-Fenney, Amie J.; Walters, Kevin B.; Nicora, Carrie D.; Purvine, Samuel O.; Casey, Cameron P.; Monroe, Matthew E.; Weitz, Karl K.; Stratton, Kelly G.; Webb-Robertson, Bobbie-Jo M.; Gralinski, Lisa; Metz, Thomas O.; Smith, Richard D.; Waters, Katrina M.; Sims, Amy C.; Kawaoka, Yoshihiro; Baric, Ralph

    2018-01-16

    Convergent evolution dictates that diverse groups of viruses will target both similar and distinct host pathways in order to manipulate the immune response and improve infection. In this study, we sought to leverage this uneven viral antagonism to identify critical host factors that govern disease outcome. Utilizing a systems based approach, we examined differential regulation of IFNγ dependent genes following infection with highly pathogenic viruses including influenza (H5N1-VN1203, H1N1-CA04) and coronaviruses (SARS-CoV, MERS-CoV). Categorizing by function, we observed down regulation of genes associated with antigen presentation following both H5N1-VN1203 and MERS-CoV infection. Further examination revealed global down regulation of antigen presentation genes and was confirmed by proteomics for both H5N1-VN1203 and MERS-CoV infection. Importantly, epigenetic analysis suggested that DNA methylation rather than histone modification plays a crucial role in MERS-CoV mediated antagonism of antigen presentation genes; in contrast, H5N1-VN1203 likely utilizes a combination of epigenetic mechanisms to target antigen presentation. Together, the results indicate a common approach utilized by H5N1-VN1203 and MERS-CoV to modulate antigen presentation and the host adaptive immune response.

  8. Casos autodeclarados de síndrome gripal en trabajadores sanitarios españoles durante la pandemia de gripe A (H1N1 2009 Self-reported cases of influenza among Spanish healthcare workers during the 2009 influenza A(H1N1 pandemic

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    Julián Olalla

    2013-04-01

    Full Text Available Objetivos: Describir la prevalencia de síndrome gripal en el invierno de 2009 y los factores asociados a su ocurrencia. Método: Estudio transversal en 18 hospitales españoles. Los voluntarios respondieron un cuestionario de salud, informando sobre si habían sufrido síndrome gripal y su estado vacunal. Resultados: Participaron 1289 trabajadores sanitarios, y de ellos, 72 (5,6% refirieron gripe en su familia, 195 (15,1% se vacunaron frente al virus A/California/7/2009/H1N1 y 75 (5,8%, intervalo de confianza del 95% [IC95%]: 4,5-7,1 sufrieron síndrome gripal. Hubo diferencias entre comunidades autónomas. En el análisis de regresión logística, se asoció a síndrome gripal trabajar en la Comunidad de Madrid (odds ratio [OR]=8,31, IC95%: 1.05-65.39, tener casos de gripe en la familia (OR=2,84, IC95%: 1,41-5,73 y no estar vacunado frente a la gripe A (OR=2,68, IC95%: 1,05-6,82. Conclusiones: La presencia de casos en la familia y la comunidad donde se trabaja determinaron una diferente prevalencia de síndrome gripal. La vacuna se asoció a una menor prevalencia de la enfermedad.Objectives: To describe the prevalence of influenza-like syndrome in winter 2009 and the factors associated with its occurrence. Methods: A cross-sectional study was carried out in 18 hospitals in Spain. Volunteers completed a health questionnaire in which they reported the occurrence of influenza-like syndrome and vaccination and demographic status. Results: A total of 1,289 healthcare workers participated. Of these, 72 (5.6% reported influenza in their family, 195 (15.1% had been vaccinated against the A/California/7/2009/H1N1 virus and 75 (5.8%, 95%CI: 4.5-7.1% had been diagnosed with influenza like-syndrome. There were differences among regions. In logistic regression analysis, the following factors were associated with a higher prevalence of influenza-like syndrome: working in Madrid (OR=8.31, 95%CI: 1.05-65.39, the occurrence of cases of influenza in the family

  9. Different environmental drivers of highly pathogenic avian influenza H5N1 outbreaks in poultry and wild birds

    NARCIS (Netherlands)

    Si, Y.; Boer, de W.F.; Gong, P.

    2013-01-01

    A large number of highly pathogenic avian influenza (HPAI) H5N1 outbreaks in poultry and wild birds have been reported in Europe since 2005. Distinct spatial patterns in poultry and wild birds suggest that different environmental drivers and potentially different spread mechanisms are operating.

  10. Early Outbreak of 2009 Influenza A (H1N1) in Mexico Prior to Identification of pH1N1 Virus

    Science.gov (United States)

    Hsieh, Ying-Hen; Ma, Stefan; Velasco Hernandez, Jorge X.; Lee, Vernon J.; Lim, Wei Yen

    2011-01-01

    Background In the aftermath of the global spread of 2009 influenza A (pH1N1) virus, still very little is known of the early stages of the outbreak in Mexico during the early months of the year, before the virus was identified. Methodology/Main Findings We fit a simple mathematical model, the Richards model, to the number of excess laboratory-confirmed influenza cases in Mexico and Mexico City during the first 15 weeks in 2009 over the average influenza case number of the previous five baseline years of 2004-2008 during the same period to ascertain the turning point (or the peak incidence) of a wave of early influenza infections, and to estimate the transmissibility of the virus during these early months in terms of its basic reproduction number. The results indicate that there may have been an early epidemic in Mexico City as well as in all of Mexico during February/March. Based on excess influenza cases, the estimated basic reproduction number R0 for the early outbreak was 1.59 (0.55 to 2.62) for Mexico City during weeks 5–9, and 1.25 (0.76, 1.74) for all of Mexico during weeks 5–14. Conclusions We established the existence of an early epidemic in Mexico City and in all of Mexico during February/March utilizing the routine influenza surveillance data, although the location of seeding is unknown. Moreover, estimates of R0 as well as the time of peak incidence (the turning point) for Mexico City and all of Mexico indicate that the early epidemic in Mexico City in February/March had been more transmissible (larger R0) and peaked earlier than the rest of the country. Our conclusion lends support to the possibility that the virus could have already spread to other continents prior to the identification of the virus and the reporting of lab-confirmed pH1N1 cases in North America in April. PMID:21909366

  11. A reverse genetic analysis of human Influenza A virus H1N2

    OpenAIRE

    Anton, Aline

    2010-01-01

    Reassortment between influenza A viruses of different subtypes rarely appears. Even in a community where H1N1 and H3N2 viruses co-circulate, reassortment to produce persistent viruses of mixed gene segments does not readily occur. H1N2 viruses, that circulated between 2001-2003 were considered to have arisen through the reassortment of the two human influenza subtypes H1N1 and H3N2. Due to the fact they make such a rare appearance, H1N2 viruses used to have new characteristics compared to the...

  12. Influenza Virus A (H1N1) in Giant Anteaters (Myrmecophaga tridactyla)

    OpenAIRE

    Nofs, Sally; Abd-Eldaim, Mohamed; Thomas, Kathy V.; Toplon, David; Rouse, Dawn; Kennedy, Melissa

    2009-01-01

    In February 2007, an outbreak of respiratory disease occurred in a group of giant anteaters (Myrmecophaga tridactyla) at the Nashville Zoo. Isolates from 2 affected animals were identified in March 2007 as a type A influenza virus related to human influenza subtype H1N1.

  13. Influenza virus A (H1N1) in giant anteaters (Myrmecophaga tridactyla).

    Science.gov (United States)

    Nofs, Sally; Abd-Eldaim, Mohamed; Thomas, Kathy V; Toplon, David; Rouse, Dawn; Kennedy, Melissa

    2009-07-01

    In February 2007, an outbreak of respiratory disease occurred in a group of giant anteaters (Myrmecophaga tridactyla) at the Nashville Zoo. Isolates from 2 affected animals were identified in March 2007 as a type A influenza virus related to human influenza subtype H1N1.

  14. Characterization of a newly emerged genetic cluster of H1N1 and H1N2 swine influenza virus in the United States.

    Science.gov (United States)

    Vincent, Amy L; Ma, Wenjun; Lager, Kelly M; Gramer, Marie R; Richt, Juergen A; Janke, Bruce H

    2009-10-01

    H1 influenza A viruses that were distinct from the classical swine H1 lineage were identified in pigs in Canada in 2003–2004; antigenic and genetic characterization identified the hemagglutinin (HA) as human H1 lineage. The viruses identified in Canadian pigs were human lineage in entirety or double (human–swine) reassortants. Here, we report the whole genome sequence analysis of four human-like H1 viruses isolated from U.S. swine in 2005 and 2007. All four isolates were characterized as triple reassortants with an internal gene constellation similar to contemporary U.S. swine influenza virus (SIV), with HA and neuraminidase (NA) most similar to human influenza virus lineages. A 2007 human-like H1N1 was evaluated in a pathogenesis and transmission model and compared to a 2004 reassortant H1N1 SIV isolate with swine lineage HA and NA. The 2007 isolate induced disease typical of influenza virus and was transmitted to contact pigs; however, the kinetics and magnitude differed from the 2004 H1N1 SIV. This study indicates that the human-like H1 SIV can efficiently replicate and transmit in the swine host and now co-circulates with contemporary SIVs as a distinct genetic cluster of H1 SIV.

  15. Inefficient transmission of H5N1 influenza viruses in a ferret contact model.

    Science.gov (United States)

    Yen, Hui-Ling; Lipatov, Aleksandr S; Ilyushina, Natalia A; Govorkova, Elena A; Franks, John; Yilmaz, Neziha; Douglas, Alan; Hay, Alan; Krauss, Scott; Rehg, Jerold E; Hoffmann, Erich; Webster, Robert G

    2007-07-01

    The abilities to infect and transmit efficiently among humans are essential for a novel influenza A virus to cause a pandemic. To evaluate the pandemic potential of widely disseminated H5N1 influenza viruses, a ferret contact model using experimental groups comprised of one inoculated ferret and two contact ferrets was used to study the transmissibility of four human H5N1 viruses isolated from 2003 to 2006. The effects of viral pathogenicity and receptor binding specificity (affinity to synthetic sialosaccharides with alpha2,3 or alpha2,6 linkages) on transmissibility were assessed. A/Vietnam/1203/04 and A/Vietnam/JP36-2/05 viruses, which possess "avian-like" alpha2,3-linked sialic acid (SA) receptor specificity, caused neurological symptoms and death in ferrets inoculated with 10(3) 50% tissue culture infectious doses. A/Hong Kong/213/03 and A/Turkey/65-596/06 viruses, which show binding affinity for "human-like" alpha2,6-linked SA receptors in addition to their affinity for alpha2,3-linked SA receptors, caused mild clinical symptoms and were not lethal to the ferrets. No transmission of A/Vietnam/1203/04 or A/Turkey/65-596/06 virus was detected. One contact ferret developed neutralizing antibodies to A/Hong Kong/213/03 but did not exhibit any clinical signs or detectable virus shedding. In two groups, one of two naïve contact ferrets had detectable virus after 6 to 8 days when housed together with the A/Vietnam/JP36-2/05 virus-inoculated ferrets. Infected contact ferrets showed severe clinical signs, although little or no virus was detected in nasal washes. This limited virus shedding explained the absence of secondary transmission from the infected contact ferret to the other naïve ferret that were housed together. Our results suggest that despite their receptor binding affinity, circulating H5N1 viruses retain molecular determinants that restrict their spread among mammalian species.

  16. Evaluation of the Cepheid Xpert Flu Assay for rapid identification and differentiation of influenza A, influenza A 2009 H1N1, and influenza B viruses.

    Science.gov (United States)

    Novak-Weekley, S M; Marlowe, E M; Poulter, M; Dwyer, D; Speers, D; Rawlinson, W; Baleriola, C; Robinson, C C

    2012-05-01

    The Xpert Flu Assay cartridge is a next-generation nucleic acid amplification system that provides multiplexed PCR detection of the influenza A, influenza A 2009 H1N1, and influenza B viruses in approximately 70 min with minimal hands-on time. Six laboratories participated in a clinical trial comparing the results of the new Cepheid Xpert Flu Assay to those of culture or real-time PCR with archived and prospectively collected nasal aspirate-wash (NA-W) specimens and nasopharyngeal (NP) swabs from children and adults. Discrepant results were resolved by DNA sequence analysis. After discrepant-result analysis, the sensitivities of the Xpert Flu Assay for prospective NA-W specimens containing the influenza A, influenza A 2009 H1N1, and influenza B viruses compared to those of culture were 90.0%, 100%, and 100%, respectively, while the sensitivities of the assay for prospective NP swabs compared to those of culture were 100%, 100%, and 100%, respectively. The sensitivities of the Xpert Flu Assay for archived NA-W specimens compared to those of Gen-Probe ProFlu+ PCR for the influenza A, influenza A 2009 H1N1, and influenza B viruses were 99.4%, 98.4%, and 100%, respectively, while the sensitivities of the Xpert Flu Assay for archived NP swabs compared to those of ProFlu+ were 98.1%, 100%, and 93.8%, respectively. The sensitivities of the Xpert Flu Assay with archived NP specimens compared to those of culture for the three targets were 97.5%, 100%, and 93.8%, respectively. We conclude that the Cepheid Xpert Flu Assay is an accurate and rapid method that is suitable for on-demand testing for influenza viral infection.

  17. Willingness to accept H1N1 pandemic influenza vaccine: A cross-sectional study of Hong Kong community nurses

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    Wong Carmen

    2010-10-01

    Full Text Available Abstract Background The 2009 pandemic of influenza A (H1N1 infection has alerted many governments to make preparedness plan to control the spread of influenza A (H1N1 infection. Vaccination for influenza is one of the most important primary preventative measures to reduce the disease burden. Our study aims to assess the willingness of nurses who work for the community nursing service (CNS in Hong Kong on their acceptance of influenza A (H1N1 influenza vaccination. Methods 401 questionnaires were posted from June 24, 2009 to June 30, 2009 to community nurses with 67% response rate. Results of the 267 respondents on their willingness to accept influenza A (H1N1 vaccine were analyzed. Results Twenty-seven percent of respondents were willing to accept influenza vaccination if vaccines were available. Having been vaccinated for seasonable influenza in the previous 12 months were significantly independently associated with their willingness to accept influenza A (H1N1 vaccination (OR = 4.03; 95% CI: 2.03-7.98. Conclusions Similar to previous findings conducted in hospital healthcare workers and nurses, we confirmed that the willingness of community nurses to accept influenza A (H1N1 vaccination is low. Future studies that evaluate interventions to address nurses' specific concerns or interventions that aim to raise the awareness among nurses on the importance of influenza A (H1N1 vaccination to protect vulnerable patient populations is needed.

  18. Intercontinental circulation of human influenza A(H1N2) reassortant viruses during the 2001-2002 influenza season.

    Science.gov (United States)

    Xu, Xiyan; Smith, Catherine B; Mungall, Bruce A; Lindstrom, Stephen E; Hall, Henrietta E; Subbarao, Kanta; Cox, Nancy J; Klimov, Alexander

    2002-11-15

    Reassortant influenza A viruses bearing the H1 subtype of hemagglutinin (HA) and the N2 subtype of neuraminidase (NA) were isolated from humans in the United States, Canada, Singapore, Malaysia, India, Oman, Egypt, and several countries in Europe during the 2001-2002 influenza season. The HAs of these H1N2 viruses were similar to that of the A/New Caledonia/20/99(H1N1) vaccine strain both antigenically and genetically, and the NAs were antigenically and genetically related to those of recent human H3N2 reference strains, such as A/Moscow/10/99(H3N2). All 6 internal genes of the H1N2 reassortants examined originated from an H3N2 virus. This article documents the first widespread circulation of H1N2 reassortants on 4 continents. The current influenza vaccine is expected to provide good protection against H1N2 viruses, because it contains the A/New Caledonia/20/99(H1N1) and A/Moscow/10/99(H3N2)-like viruses, which have H1 and N2 antigens that are similar to those of recent H1N2 viruses.

  19. Epidemiological characteristics of the influenza A(H1N1 2009 pandemic in the Western Pacific Region

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    Lisa McCallum

    2010-12-01

    Full Text Available The first laboratory-confirmed cases of infection with pandemic influenza A(H1N1 2009 in the Western Pacific Region were reported on 28 April 2009. By 11 June 2009, the day the pandemic was declared by the World Health Organization, nine Western Pacific Region countries and areas had reported laboratory-confirmed pandemic influenza A(H1N1 2009 cases. From April 2009 to July 2010, more than 250 000 cases and 1800 deaths from laboratory-confirmed pandemic influenza A(H1N1 2009 were reported from 34 countries and areas in the Region. By age group region-wide, 8.6%, 41.9%, 48.3%, and 1.2% of cases were in the < 5 years, 5–14 years, 15–64 years, and 65+ years age groups, respectively; the overall crude case fatality ratio in the Western Pacific Region was 0.5%. The pandemic demonstrated that region-wide disease reporting was possible. Countries and areas of the Western Pacific Region should take this opportunity to strengthen the systems established during the pandemic to develop routine disease reporting.

  20. [Differences in oligomerization of nucleocapsid protein of epidemic human influenza A(H1N1), A(H1N2) and B viruses].

    Science.gov (United States)

    Prokudina, E N; Semenova, N P; Chumakov, V M; Burtseva, E I; Slepushkin, A N

    2003-01-01

    A comparative analysis of involving the nucleocapsid protein (NP) into shaping-up of SDS-resistant oligomers was carried out presently in circulating epidemic strains of human influenza, viruses A and B. The study results of viral isolates obtained from clinical samples and recent standard strains revealed that the involvement of NP in the SDS-resistant oligomers, which are different in various subtypes of influenza A viruses. According to this sign, the human viruses A(9H3N2) are close to the avian ones, in which, as proved by us previously, virtually the entire NP transforms itself into the oligomers resistant to SDS. About 10-20% of NP are involved in shaping-up the virus influenza A(H1N1) of SDS-resistant oligomers. No SDS-resistant NP-oligomers were detected in influenza of type B. It is suggested that the prevalence of human viruses A(H3N2) in NP-oligomers are the peculiarities of NP structure and of the presence of the PB1 protein from avian influenza virus.

  1. Risk factors affecting seroconversion after influenza A/H1N1 vaccination in hemodialysis patients

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    Moon Sung Jin

    2012-12-01

    Full Text Available Abstracts Background Hemodialysis (HD patients have multiple causes of immune dysfunction and poor immune response to influenza vaccination. We investigated the antibody response rate to a pandemic H1N1/2009 influenza vaccination and clinical parameters influencing the induction of antibody responses in HD patients. Methods A total of 114 HD patients were vaccinated with a monovalent adjuvanted H1N1 inactivated influenza vaccine. Titers of neutralizing antibodies were evaluated by hemagglutination inhibition (HI assay at pre- and 4 weeks after vaccination. Seroconversion was defined as either a pre-vaccination HI titer  1:40 or a pre-vaccination HI titer ≥ 1:10 and a minimum four-fold rise in post-vaccination HI antibody titer. Seventeen out of 114 HD patients (14.9% tested positive for antibodies against influenza A/H1N1/2009 before vaccination. The remaining 97 baseline sero-negative patients were included in the analysis. Results Only 30 (30.9% HD patients had seroconversion 4 weeks after vaccination. The elderly patients, those over 65 years of age, showed significantly lower seroconversion rate compared to younger HD patients (20.5% vs. 39.6%, p = 0.042. Furthermore, patients with hemoglobin values less than 10 g/dL had a significantly lower seroconversion rate compared to those with higher hemoglobin values (20.0 vs. 38.6%, p = 0.049. By multivariate logistic regression analysis, only age ≥65 years (OR = 0.336, 95% confidence interval (CI 0.116-0.971, p = 0.044 and hemoglobin levels Conclusions Our data show that HD patients, especially who are elderly with low hemoglobin levels, are at increased risk for lower seroconversion rate after influenza A/H1N1 vaccination. Further studies are needed to improve the efficacy of vaccination in these high risk patients.

  2. Epidemiological assessment of influenza (H1N1- A in patients hospitalized in Tohid hospital in Sanandaj, Iran during 2013-2014

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    Houshiyar Ghafouri

    2016-12-01

    Full Text Available Background: Influenza is an acute respiratory infection caused by influenza virus which is highly contagious and spread easily. Objectives: The aim of this study was to evaluate the epidemiology of influenza (H1N1 type A in patients admitted to Tohid hospital, Sanandaj, Iran during 2013-2014. Material and Methods: This study was descriptive. Data were collected using a questionnaire which was designed based on study goals. The questionnaires were completed via interview, observation and performing clinical tests. After clinical confirmation of influenza by a specialist, genotype was determined by PCR. Results: Of the total 76 cases, 36 cases (48.6% were male, mean age was 42.7 ± 16.3 and 13.5% were rural and 86.5 were urban dwellers. 52 patient (70.3% were hospitalized and 22 (29.7% were outpatients. Travel history was including, abroad 9.5%, domestic 16.2% and without traveling 75.3%. The average time between referring to the doctor and sampling for H1N1 was 2.7 days. The prevalence of influenza (H1N1 A was 1.4%. Conclusion: The low incidence of H1N1 influenza type A in this study was probably due to travel to infected areas. Considering virus mutation, the readiness of health services to prevent an epidemic of this disease is essential and recommended.

  3. Outbreak of H3N2 influenza at a US military base in Djibouti during the H1N1 pandemic of 2009.

    Science.gov (United States)

    Cosby, Michael T; Pimentel, Guillermo; Nevin, Remington L; Fouad Ahmed, Salwa; Klena, John D; Amir, Ehab; Younan, Mary; Browning, Robert; Sebeny, Peter J

    2013-01-01

    Influenza pandemics have significant operational impact on deployed military personnel working in areas throughout the world. The US Department of Defense global influenza-like illness (ILI) surveillance network serves an important role in establishing baseline trends and can be leveraged to respond to outbreaks of respiratory illness. We identified and characterized an operationally unique outbreak of H3N2 influenza at Camp Lemonnier, Djibouti occurring simultaneously with the H1N1 pandemic of 2009 [A(H1N1)pdm09]. Enhanced surveillance for ILI was conducted at Camp Lemonnier in response to local reports of a possible outbreak during the A(H1N1)pdm09 pandemic. Samples were collected from consenting patients presenting with ILI (utilizing a modified case definition) and who completed a case report form. Samples were cultured and analyzed using standard real-time reverse transcriptase PCR (rt-RT-PCR) methodology and sequenced genetic material was phylogenetically compared to other published strains. rt-RT-PCR and DNA sequencing revealed that 25 (78%) of the 32 clinical samples collected were seasonal H3N2 and only 2 (6%) were A(H1N1)pdm09 influenza. The highest incidence of H3N2 occurred during the month of May and 80% of these were active duty military personnel. Phylogenetic analysis revealed that sequenced H3N2 strains were genetically similar to 2009 strains from the United States of America, Australia, and South east Asia. This outbreak highlights challenges in the investigation of influenza among deployed military populations and corroborates the public health importance of maintaining surveillance systems for ILI that can be enhanced locally when needed.

  4. Assessing Google flu trends performance in the United States during the 2009 influenza virus A (H1N1 pandemic.

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    Samantha Cook

    Full Text Available BACKGROUND: Google Flu Trends (GFT uses anonymized, aggregated internet search activity to provide near-real time estimates of influenza activity. GFT estimates have shown a strong correlation with official influenza surveillance data. The 2009 influenza virus A (H1N1 pandemic [pH1N1] provided the first opportunity to evaluate GFT during a non-seasonal influenza outbreak. In September 2009, an updated United States GFT model was developed using data from the beginning of pH1N1. METHODOLOGY/PRINCIPAL FINDINGS: We evaluated the accuracy of each U.S. GFT model by comparing weekly estimates of ILI (influenza-like illness activity with the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet. For each GFT model we calculated the correlation and RMSE (root mean square error between model estimates and ILINet for four time periods: pre-H1N1, Summer H1N1, Winter H1N1, and H1N1 overall (Mar 2009-Dec 2009. We also compared the number of queries, query volume, and types of queries (e.g., influenza symptoms, influenza complications in each model. Both models' estimates were highly correlated with ILINet pre-H1N1 and over the entire surveillance period, although the original model underestimated the magnitude of ILI activity during pH1N1. The updated model was more correlated with ILINet than the original model during Summer H1N1 (r = 0.95 and 0.29, respectively. The updated model included more search query terms than the original model, with more queries directly related to influenza infection, whereas the original model contained more queries related to influenza complications. CONCLUSIONS: Internet search behavior changed during pH1N1, particularly in the categories "influenza complications" and "term for influenza." The complications associated with pH1N1, the fact that pH1N1 began in the summer rather than winter, and changes in health-seeking behavior each may have played a part. Both GFT models performed well prior to and during pH1

  5. Assessing Google Flu Trends Performance in the United States during the 2009 Influenza Virus A (H1N1) Pandemic

    Science.gov (United States)

    Cook, Samantha; Conrad, Corrie; Fowlkes, Ashley L.; Mohebbi, Matthew H.

    2011-01-01

    Background Google Flu Trends (GFT) uses anonymized, aggregated internet search activity to provide near-real time estimates of influenza activity. GFT estimates have shown a strong correlation with official influenza surveillance data. The 2009 influenza virus A (H1N1) pandemic [pH1N1] provided the first opportunity to evaluate GFT during a non-seasonal influenza outbreak. In September 2009, an updated United States GFT model was developed using data from the beginning of pH1N1. Methodology/Principal Findings We evaluated the accuracy of each U.S. GFT model by comparing weekly estimates of ILI (influenza-like illness) activity with the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet). For each GFT model we calculated the correlation and RMSE (root mean square error) between model estimates and ILINet for four time periods: pre-H1N1, Summer H1N1, Winter H1N1, and H1N1 overall (Mar 2009–Dec 2009). We also compared the number of queries, query volume, and types of queries (e.g., influenza symptoms, influenza complications) in each model. Both models' estimates were highly correlated with ILINet pre-H1N1 and over the entire surveillance period, although the original model underestimated the magnitude of ILI activity during pH1N1. The updated model was more correlated with ILINet than the original model during Summer H1N1 (r = 0.95 and 0.29, respectively). The updated model included more search query terms than the original model, with more queries directly related to influenza infection, whereas the original model contained more queries related to influenza complications. Conclusions Internet search behavior changed during pH1N1, particularly in the categories “influenza complications” and “term for influenza.” The complications associated with pH1N1, the fact that pH1N1 began in the summer rather than winter, and changes in health-seeking behavior each may have played a part. Both GFT models performed well prior to and during pH1N1

  6. Experimental challenge and pathology of highly pathogenic avian influenza virus H5N1 in dunlin (Calidris alpina), an intercontinental migrant shorebird species.

    Science.gov (United States)

    Hall, Jeffrey S; Franson, J Christian; Gill, Robert E; Meteyer, Carol U; TeSlaa, Joshua L; Nashold, Sean; Dusek, Robert J; Ip, Hon S

    2011-09-01

    Shorebirds (Charadriiformes) are considered one of the primary reservoirs of avian influenza. Because these species are highly migratory, there is concern that infected shorebirds may be a mechanism by which highly pathogenic avian influenza virus (HPAIV) H5N1 could be introduced into North America from Asia. Large numbers of dunlin (Calidris alpina) migrate from wintering areas in central and eastern Asia, where HPAIV H5N1 is endemic, across the Bering Sea to breeding areas in Alaska. Low pathogenic avian influenza virus has been previously detected in dunlin, and thus, dunlin represent a potential risk to transport HPAIV to North America. To date no experimental challenge studies have been performed in shorebirds. Wild dunlin were inoculated intranasally and intrachoanally various doses of HPAIV H5N1. The birds were monitored daily for virus excretion, disease signs, morbidity, and mortality. The infectious dose of HPAIV H5N1 in dunlin was determined to be 10(1.7) EID(50)/100 μl and that the lethal dose was 10(1.83) EID(50)/100 μl. Clinical signs were consistent with neurotropic disease, and histochemical analyses revealed that infection was systemic with viral antigen and RNA most consistently found in brain tissues. Infected birds excreted relatively large amounts of virus orally (10(4) EID(50)) and smaller amounts cloacally. Dunlin are highly susceptible to infection with HPAIV H5N1. They become infected after exposure to relatively small doses of the virus and if they become infected, they are most likely to suffer mortality within 3-5 days. These results have important implications regarding the risks of transport and transmission of HPAIV H5N1 to North America by this species and raises questions for further investigation. Published 2011. This article is a US Government work and is in the public domain in the USA.

  7. Immunomorphologic Manifestations in Mice Liver Infected with Influenza A/H5N1, A/Goose/Krasnoozerskoye/627/05 Strain

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    Oxana V. Potapova

    2013-01-01

    Full Text Available Highly pathogenic avian influenza H5N1 (HPAI H5N1 viruses can infect mammals, including humans, causing severe systemic disease with the inhibition of the immune system and a high mortality rate. In conditions of lymphoid tissue depletion, the liver plays an important role in host defence against viruses. The changes in mice liver infected with HPAI H5N1 virus A/goose/Krasnoozerskoye/627/05 have been studied. It has been shown that the virus persistence in the liver leads to the expression of proinflammatory cytokines (TNF-α, IL-6 and intracellular proteases (lysozyme, cathepsin D, and myeloperoxidase by Kupffer cells. Defective antiviral response exacerbates destructive processes in the liver accelerating the development of liver failure.

  8. The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant

    OpenAIRE

    Renström Lena HM; Isaksson Mats; Berg Mikael; Zohari Siamak; Widén Frederik; Metreveli Giorgi; Bálint Ádám; Wallgren Per; Belák Sándor; Segall Thomas; Kiss István

    2009-01-01

    Abstract The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority o...

  9. The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant

    Directory of Open Access Journals (Sweden)

    Renström Lena HM

    2009-10-01

    Full Text Available Abstract The European swine influenza viruses (SIVs show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA of the human-like H1N2 SIV viruses and the neuraminidase (NA of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain. The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.

  10. The first Swedish H1N2 swine influenza virus isolate represents an uncommon reassortant.

    Science.gov (United States)

    Bálint, Adám; Metreveli, Giorgi; Widén, Frederik; Zohari, Siamak; Berg, Mikael; Isaksson, Mats; Renström, Lena Hm; Wallgren, Per; Belák, Sándor; Segall, Thomas; Kiss, István

    2009-10-28

    The European swine influenza viruses (SIVs) show considerable diversity comprising different types of H1N1, H3N2, and H1N2 strains. The intensifying full genome sequencing efforts reveal further reassortants within these subtypes. Here we report the identification of an uncommon reassortant variant of H1N2 subtype influenza virus isolated from a pig in a multisite herd where H1N2 swine influenza was diagnosed for the first time in Sweden during the winter of 2008-2009. The majority of the European H1N2 swine influenza viruses described so far possess haemagglutinin (HA) of the human-like H1N2 SIV viruses and the neuraminidase (NA) of either the European H1N2 or H3N2 SIV-like viruses. The Swedish isolate has an avian-like SIV HA and a H3N2 SIV-like NA, which is phylogenetically more closely related to H3N2 SIV NAs from isolates collected in the early '80s than to the NA of H3N2 origin of the H1N2 viruses isolated during the last decade, as depicted by some German strains, indicative of independent acquisition of the NA genes for these two types of reassortants. The internal genes proved to be entirely of avian-like SIV H1N1 origin. The prevalence of this SIV variant in pig populations needs to be determined, as well as the suitability of the routinely used laboratory reagents to analyze this strain.The description of this H1N2 SIV adds further information to influenza epidemiology and supports the necessity of surveillance for influenza viruses in pigs.

  11. Two genotypes of H1N2 swine influenza viruses appeared among pigs in China.

    Science.gov (United States)

    Xu, Chuantian; Zhu, Qiyun; Yang, Huanliang; Zhang, Xiumei; Qiao, Chuanling; Chen, Yan; Xin, Xiaoguang; Chen, Hualan

    2009-10-01

    H1N2 is one of the main subtypes of influenza, which circulates in swine all over the world. To investigate the prevalence and genetic of H1N2 in swine of China. Two H1N2 swine influenza viruses were isolated from Tianjin and Guangdong province of China in 2004 and 2006, respectively. The molecular evolution of eight gene segments was analyzed. A/Swine/Tianjin/1/2004 has low identity with A/Swine/Guangdong/2006; in the phylogenetic tree of PA gene, A/Swine/Guangdong/1/2006 and A/Swine/Guangxi/1/2006 along with the H1N2 swine isolates of North America formed a cluster; and A/Swine/Tianjin/2004 and A/Swine/Zhejiang/2004, along with the classical H1N1 swine isolates formed another cluster; except that NA gene of A/Swine/Tianjin/1/2004 fell into the cluster of the H3N2 human influenza virus, indicating the reassortment between H3N2 human and H1N1 swine influenza viruses. Two different genotypes of H1N2 appeared among pigs in China. A/swine/Guangdong/1/06 was probably from H1N2 swine influenza viruses of North America; while A/swine/Tianjin/1/04 maybe come from reassortments of classical H1N1 swine and H3N2 human viruses prevalent in North America.

  12. Radiographic study of severe Influenza-A (H1N1) disease in children

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Cailei, E-mail: zhaocailei197866@163.com [Department of Radiology, Shenzhen Children' s Hospital, No. 7019, Yitian Road, Futian District, Shenzhen 518026 (China); Gan Yungen, E-mail: mickeyym@yahoo.cn [Department of Radiology, Shenzhen Children' s Hospital, No. 7019, Yitian Road, Futian District, Shenzhen 518026 (China); Sun Jie, E-mail: sunxixi@21cn.com [Department of Radiology, Shenzhen Children' s Hospital, No. 7019, Yitian Road, Futian District, Shenzhen 518026 (China)

    2011-09-15

    Objective: To characterize the radiographic findings of pediatric patients with severe Influenza-A (H1N1) disease. Methods: A retrospective study of data from chest X-ray, CT and MRI exam of 29 pediatric patients treated in intensive care unit for severe Influenza-A (H1N1) disease. Results: Disease developed quickly at early stage. Here are four types of radiographic findings. The disease continued to progress for 2-3 days and X-ray showed that all 29 patients had increased solid lesions with the existence of interstitial lesions. Four days later, all lung lesions showed absorption to certain degree. Fifteen days later, X-ray and CT showed complete or significant absorption in 19 cases (85.5%); delayed recovery was identified in 8 cases (27.6%), pulmonary fibrosis was found in 3 cases (10.3%), and 3 patients (10.3%) died. But the latter identified more lesions. Cranial CT and MRI were performed for 8 patients who had neurological symptoms. Of them, 3 cases (10.3%) were abnormal, showed symmetrical long T1 and T2 signal shadow in bilateral thalamus and longer T1 and T2 signals in the between. 3 cases had autopsy completed. Conclusion: The severe Influenza-A (H1N1) among children progression was generally rapid in the first 3 days. The overall radiographic findings are similar to acute respiratory distress syndrome (ARDS). A small portion of the patients occurred acute necrotizing encephalopathy and plastic bronchitis.

  13. Radiographic study of severe Influenza-A (H1N1) disease in children

    International Nuclear Information System (INIS)

    Zhao Cailei; Gan Yungen; Sun Jie

    2011-01-01

    Objective: To characterize the radiographic findings of pediatric patients with severe Influenza-A (H1N1) disease. Methods: A retrospective study of data from chest X-ray, CT and MRI exam of 29 pediatric patients treated in intensive care unit for severe Influenza-A (H1N1) disease. Results: Disease developed quickly at early stage. Here are four types of radiographic findings. The disease continued to progress for 2-3 days and X-ray showed that all 29 patients had increased solid lesions with the existence of interstitial lesions. Four days later, all lung lesions showed absorption to certain degree. Fifteen days later, X-ray and CT showed complete or significant absorption in 19 cases (85.5%); delayed recovery was identified in 8 cases (27.6%), pulmonary fibrosis was found in 3 cases (10.3%), and 3 patients (10.3%) died. But the latter identified more lesions. Cranial CT and MRI were performed for 8 patients who had neurological symptoms. Of them, 3 cases (10.3%) were abnormal, showed symmetrical long T1 and T2 signal shadow in bilateral thalamus and longer T1 and T2 signals in the between. 3 cases had autopsy completed. Conclusion: The severe Influenza-A (H1N1) among children progression was generally rapid in the first 3 days. The overall radiographic findings are similar to acute respiratory distress syndrome (ARDS). A small portion of the patients occurred acute necrotizing encephalopathy and plastic bronchitis.

  14. Trivalent influenza vaccine in patients on haemodialysis: impaired seroresponse with differences for A-H3N2 and A-H1N1 vaccine components

    NARCIS (Netherlands)

    W.E.Ph. Beyer (Walter); D.J. Versluis; P. Kramer; P.P.N.M. Diderich (Philip); W. Weimar (Willem); N. Masurel (Nic)

    1987-01-01

    textabstractOne hundred and one patients on haemodialysis, 21 patients on peritoneal dialysis and 30 healthy controls received a trivalent split vaccine containing 15 micrograms haemagglutinin of a recent influenza A-H3N2, influenza A-H1N1 and influenza B strain, respectively. Antibody production

  15. Risk factors and clusters of Highly Pathogenic Avian Influenza H5N1 outbreaks in Bangladesh

    Science.gov (United States)

    Loth, Leo; Gilbert, Marius; Osmani, Mozaffar G.; Kalam, Abul M.; Xiao, Xiangming

    2016-01-01

    Between March 2007 and July 2009, 325 Highly Pathogenic Avian Influenza (HPAI, subtype H5N1) outbreaks in poultry were reported in 154 out of a total of 486 sub-districts in Bangladesh. This study analyzed the temporal and spatial patterns of HPAI H5N1 outbreaks and quantified the relationship between several spatial risk factors and HPAI outbreaks in sub-districts in Bangladesh. We assessed spatial autocorrelation and spatial dependence, and identified clustering sub-districts with disease statistically similar to or dissimilar from their neighbors. Three significant risk factors associated to HPAI H5N1 virus outbreaks were identified; the quadratic log-transformation of human population density [humans per square kilometer, P = 0.01, OR 1.15 (95% CI: 1.03–1.28)], the log-transformation of the total commercial poultry population [number of commercial poultry per sub-district, P Bangladesh to target surveillance and to concentrate response efforts in areas where disease is likely to occur. Concentrating response efforts may help to combat HPAI more effectively, reducing the environmental viral load and so reducing the number of disease incidents. PMID:20554337

  16. Insight into Alternative Approaches for Control of Avian Influenza in Poultry, with Emphasis on Highly Pathogenic H5N1

    Directory of Open Access Journals (Sweden)

    Hafez M. Hafez

    2012-11-01

    Full Text Available Highly pathogenic avian influenza virus (HPAIV of subtype H5N1 causes a devastating disease in poultry but when it accidentally infects humans it can cause death. Therefore, decrease the incidence of H5N1 in humans needs to focus on prevention and control of poultry infections. Conventional control strategies in poultry based on surveillance, stamping out, movement restriction and enforcement of biosecurity measures did not prevent the virus spreading, particularly in developing countries. Several challenges limit efficiency of the vaccines to prevent outbreaks of HPAIV H5N1 in endemic countries. Alternative and complementary approaches to reduce the current burden of H5N1 epidemics in poultry should be encouraged. The use of antiviral chemotherapy and natural compounds, avian-cytokines, RNA interference, genetic breeding and/or development of transgenic poultry warrant further evaluation as integrated intervention strategies for control of HPAIV H5N1 in poultry.

  17. Protection of human influenza vaccines against a reassortant swine influenza virus of pandemic H1N1 origin using a pig model.

    Science.gov (United States)

    Arunorat, Jirapat; Charoenvisal, Nataya; Woonwong, Yonlayong; Kedkovid, Roongtham; Jittimanee, Supattra; Sitthicharoenchai, Panchan; Kesdangsakonwut, Sawang; Poolperm, Pariwat; Thanawongnuwech, Roongroje

    2017-10-01

    Since the pandemic H1N1 emergence in 2009 (pdmH1N1), many reassortant pdmH1N1 viruses emerged and found circulating in the pig population worldwide. Currently, commercial human subunit vaccines are used commonly to prevent the influenza symptom based on the WHO recommendation. In case of current reassortant swine influenza viruses transmitting from pigs to humans, the efficacy of current human influenza vaccines is of interest. In this study, influenza A negative pigs were vaccinated with selected commercial human subunit vaccines and challenged with rH3N2. All sera were tested with both HI and SN assays using four representative viruses from the surveillance data in 2012 (enH1N1, pdmH1N1, rH1N2 and rH3N2). The results showed no significant differences in clinical signs and macroscopic and microscopic findings among groups. However, all pig sera from vaccinated groups had protective HI titers to the enH1N1, pdmH1N1 and rH1N2 at 21DPV onward and had protective SN titers only to pdmH1N1and rH1N2 at 21DPV onward. SN test results appeared more specific than those of HI tests. All tested sera had no cross-reactivity against the rH3N2. Both studied human subunit vaccines failed to protect and to stop viral shedding with no evidence of serological reaction against rH3N2. SIV surveillance is essential for monitoring a novel SIV emergence potentially for zoonosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Clinical characteristics and outcomes among pediatric patients hospitalized with pandemic influenza A/H1N1 2009 infection

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    Eun Lee

    2011-08-01

    Full Text Available Purpose : The purpose of this article is to describe the clinical and epidemiologic features and outcomes among children hospitalized with pandemic influenza A/H1N1 2009 infection. Methods : We retrospectively reviewed the charts of hospitalized pediatric patients (&lt;18 years diagnosed with pandemic influenza A/H1N1 2009 infection by reverse-transcriptase polymerase chain reaction at a tertiary hospital in Seoul, Korea, between September 2009 and February 2010. Results : A total of 72 children were hospitalized with pandemic influenza A/H1N1 2009 infection (median age, 6.0 years; range, 2 months to 18 years. A total of 40% had at least 1 underlying medical condition, including asthma (17%, malignancies (19%, and heart diseases (17%. Of the 72 patients, 54 (76% children admitted with H1N1 infection showed radiographic alterations compatible with pneumonia. There was no significant difference in pre-existing conditions between pandemic influenza A/H1N1 infected patients with or without pneumonia. Children with pandemic influenza A/ H1N1 pneumonia were more likely to have a lower lymphocyte ratio (P=0.02, higher platelet count (P=0.02, and higher level of serum glucose (P=0.003, and more commonly presented with dyspnea than did those without pneumonia (P=0.04. Conclusion : No significant differences in age, sex, or presence of preexisting conditions were found between children hospitalized with pandemic influenza A/H1N1 H1N1 influenza infection with pneumonia and those without pneumonia. Higher leukocyte count, higher glucose level, and a lower lymphocyte ratio were associated with the development of pandemic A/H1N1 2009 influenza pneumonia.

  19. The seroprevalence of pandemic influenza H1N1 (2009 virus in China.

    Directory of Open Access Journals (Sweden)

    Cuiling Xu

    2011-04-01

    Full Text Available Mainland China experienced pandemic influenza H1N1 (2009 virus (pH1N1 with peak activity during November-December 2009. To understand the geographic extent, risk factors, and attack rate of pH1N1 infection in China we conducted a nationwide serological survey to determine the prevalence of antibodies to pH1N1.Stored serum samples (n = 2,379 collected during 2006-2008 were used to estimate baseline serum reactogenicity to pH1N1. In January 2010, we used a multistage-stratified random sampling method to select 50,111 subjects who met eligibility criteria and collected serum samples and administered a standardized questionnaire. Antibody response to pH1N1 was measured using haemagglutination inhibition (HI assay and the weighted seroprevalence was calculated using the Taylor series linearization method. Multivariable logistic regression analyses were used to examine risk factors for pH1N1 seropositivity. Baseline seroprevalence of pH1N1 antibody (HI titer ≥40 was 1.2%. The weighted seroprevalence of pH1N1 among the Chinese population was 21.5%(vaccinated: 62.0%; unvaccinated: 17.1%. Among unvaccinated participants, those aged 6-15 years (32.9% and 16-24 years (30.3% had higher seroprevalence compared with participants aged 25-59 years (10.7% and ≥60 years (9.9%, P<0.0001. Children in kindergarten and students had higher odds of seropositivity than children in family care (OR: 1.36 and 2.05, respectively. We estimated that 207.7 million individuals (15.9% experienced pH1N1 infection in China.The Chinese population had low pre-existing immunity to pH1N1 and experienced a relatively high attack rate in 2009 of this virus. We recommend routine control measures such as vaccination to reduce transmission and spread of seasonal and pandemic influenza viruses.

  20. A historical perspective of influenza A(H1N2) virus.

    Science.gov (United States)

    Komadina, Naomi; McVernon, Jodie; Hall, Robert; Leder, Karin

    2014-01-01

    The emergence and transition to pandemic status of the influenza A(H1N1)A(H1N1)pdm09) virus in 2009 illustrated the potential for previously circulating human viruses to re-emerge in humans and cause a pandemic after decades of circulating among animals. Within a short time of the initial emergence of A(H1N1)pdm09 virus, novel reassortants were isolated from swine. In late 2011, a variant (v) H3N2 subtype was isolated from humans, and by 2012, the number of persons infected began to increase with limited person-to-person transmission. During 2012 in the United States, an A(H1N2)v virus was transmitted to humans from swine. During the same year, Australia recorded its first H1N2 subtype infection among swine. The A(H3N2)v and A(H1N2)v viruses contained the matrix protein from the A(H1N1)pdm09 virus, raising the possibility of increased transmissibility among humans and underscoring the potential for influenza pandemics of novel swine-origin viruses. We report on the differing histories of A(H1N2) viruses among humans and animals.

  1. Pandemic (H1N1 2009 Influenza Virus Infection in A Survivor who has recovered from severe H7N9 Virus Infection, China

    Directory of Open Access Journals (Sweden)

    Shan-Hui Chen

    2016-10-01

    Full Text Available We firstly report a patient who presented with severe complications after infection with influenza A(H1N1 pdm2009, more than one year after recovery from severe H7N9 virus infections. The population of patients who recovered from severe H7N9 infections might be at a higher risk to suffer severe complications after seasonal influenza infections, and they should be included in the high-risk populations recommended to receive seasonal influenza vaccination.

  2. Analysis of Viral Genetics for Estimating Diffusion of Influenza A H6N1

    OpenAIRE

    Scotch, Matthew; Suchard, Marc A.; Rabinowitz, Peter M.

    2015-01-01

    H6N1 influenza A is an avian virus but in 2013 infected a human in Taiwan. We studied the phylogeography of avian origin H6N1 viruses in the Influenza Research Database and the Global Initiative on Sharing Avian Influenza Data EpiFlu Database in order to characterize their recent evolutionary spread. Our results suggest that the H6N1 virus that infected a human in Taiwan is derived from a diversity of avian strains of H6N1 that have circulated for at least seven years in this region. Understa...

  3. Novel Reassortant Influenza A(H5N8) Viruses among Inoculated Domestic and Wild Ducks, South Korea, 2014

    Science.gov (United States)

    Kang, Hyun-Mi; Lee, Eun-Kyoung; Song, Byung-Min; Jeong, Jipseol; Choi, Jun-Gu; Jeong, Joojin; Moon, Oun-Kyong; Yoon, Hachung; Cho, Youngmi; Kang, Young-Myong; Lee, Hee-Soo

    2015-01-01

    An outbreak of highly pathogenic avian influenza, caused by a novel reassortant influenza A (H5N8) virus, occurred among poultry and wild birds in South Korea in 2014. The aim of this study was to evaluate the pathogenesis in and mode of transmission of this virus among domestic and wild ducks. Three of the viruses had similar pathogenicity among infected domestic ducks: the H5N8 viruses were moderately pathogenic (0%–20% mortality rate); in wild mallard ducks, the H5N8 and H5N1 viruses did not cause severe illness or death; viral replication and shedding were greater in H5N8-infected mallards than in H5N1-infected mallards. Identification of H5N8 viruses in birds exposed to infected domestic ducks and mallards indicated that the viruses could spread by contact. We propose active surveillance to support prevention of the spread of this virus among wild birds and poultry, especially domestic ducks. PMID:25625281

  4. Detection of H5 Avian Influenza Viruses by Antigen-Capture Enzyme-Linked Immunosorbent Assay Using H5-Specific Monoclonal Antibody▿

    OpenAIRE

    He, Qigai; Velumani, Sumathy; Du, Qingyun; Lim, Chee Wee; Ng, Fook Kheong; Donis, Ruben; Kwang, Jimmy

    2007-01-01

    The unprecedented spread of highly pathogenic avian influenza virus subtype H5N1 in Asia and Europe is threatening animals and public health systems. Effective diagnosis and control management are needed to control the disease. To this end, we developed a panel of monoclonal antibodies (MAbs) against the H5N1 avian influenza virus (AIV) and implemented an antigen-capture enzyme-linked immunosorbent assay (AC-ELISA) to detect the H5 viral antigen. Mice immunized with denatured hemagglutinin (H...

  5. Supply of neuraminidase inhibitors related to reduced influenza A (H1N1) mortality during the 2009-2010 H1N1 pandemic: an ecological study.

    Science.gov (United States)

    Miller, Paula E; Rambachan, Aksharananda; Hubbard, Roderick J; Li, Jiabai; Meyer, Alison E; Stephens, Peter; Mounts, Anthony W; Rolfes, Melissa A; Penn, Charles R

    2012-01-01

    The influenza A (H1N1) pandemic swept across the globe from April 2009 to August 2010 affecting millions. Many WHO Member States relied on antiviral drugs, specifically neuraminidase inhibitors (NAIs) oseltamivir and zanamivir, to treat influenza patients in critical condition. Such drugs have been found to be effective in reducing severity and duration of influenza illness, and likely reduced morbidity during the pandemic. However, it is less clear whether NAIs used during the pandemic reduced H1N1 mortality. Country-level data on supply of oseltamivir and zanamivir were used to predict H1N1 mortality (per 100,000 people) from July 2009 to August 2010 in forty-two WHO Member States. Poisson regression was used to model the association between NAI supply and H1N1 mortality, with adjustment for economic, demographic, and health-related confounders. After adjustment for potential confounders, each 10% increase in kilograms of oseltamivir, per 100,000 people, was associated with a 1.6% reduction in H1N1 mortality over the pandemic period (relative rate (RR) = 0.84 per log increase in oseltamivir supply). While the supply of zanamivir was considerably less than that of oseltamivir in each Member State, each 10% increase in kilogram of active zanamivir, per 100,000, was associated with a 0.3% reduction in H1N1 mortality (RR = 0.97 per log increase). While there are limitations to the ecologic nature of these data, this analysis offers evidence of a protective relationship between antiviral drug supply and influenza mortality and supports a role for influenza antiviral use in future pandemics.

  6. Humans and ferrets with prior H1N1 influenza virus infections do not exhibit evidence of original antigenic sin after infection or vaccination with the 2009 pandemic H1N1 influenza virus.

    Science.gov (United States)

    O'Donnell, Christopher D; Wright, Amber; Vogel, Leatrice; Boonnak, Kobporn; Treanor, John J; Subbarao, Kanta

    2014-05-01

    The hypothesis of original antigenic sin (OAS) states that the imprint established by an individual's first influenza virus infection governs the antibody response thereafter. Subsequent influenza virus infection results in an antibody response against the original infecting virus and an impaired immune response against the newer influenza virus. The purpose of our study was to seek evidence of OAS after infection or vaccination with the 2009 pandemic H1N1 (2009 pH1N1) virus in ferrets and humans previously infected with H1N1 viruses with various antigenic distances from the 2009 pH1N1 virus, including viruses from 1935 through 1999. In ferrets, seasonal H1N1 priming did not diminish the antibody response to infection or vaccination with the 2009 pH1N1 virus, nor did it diminish the T-cell response, indicating the absence of OAS in seasonal H1N1 virus-primed ferrets. Analysis of paired samples of human serum taken before and after vaccination with a monovalent inactivated 2009 pH1N1 vaccine showed a significantly greater-fold rise in the titer of antibody against the 2009 pH1N1 virus than against H1N1 viruses that circulated during the childhood of each subject. Thus, prior experience with H1N1 viruses did not result in an impairment of the antibody response against the 2009 pH1N1 vaccine. Our data from ferrets and humans suggest that prior exposure to H1N1 viruses did not impair the immune response against the 2009 pH1N1 virus.

  7. Host-specific exposure and fatal neurologic disease in wild raptors from highly pathogenic avian influenza virus H5N1 during the 2006 outbreak in Germany

    NARCIS (Netherlands)

    J.M.A. van den Brand (Judith); O. Krone (Oliver); P.U. Wolf (Peter U.); M.W.G. van de Bildt (Marco); G. van Amerongen (Geert); A.D.M.E. Osterhaus (Albert); T. Kuiken (Thijs)

    2015-01-01

    textabstractRaptors may contract highly pathogenic avian influenza virus H5N1 by hunting or scavenging infected prey. However, natural H5N1 infection in raptors is rarely reported. Therefore, we tested raptors found dead during an H5N1 outbreak in wild waterbirds in Mecklenburg-Western Pomerania,

  8. Characterizing the epidemiology of the 2009 influenza A/H1N1 pandemic in Mexico.

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    Gerardo Chowell

    2011-05-01

    Full Text Available BACKGROUND: Mexico's local and national authorities initiated an intense public health response during the early stages of the 2009 A/H1N1 pandemic. In this study we analyzed the epidemiological patterns of the pandemic during April-December 2009 in Mexico and evaluated the impact of nonmedical interventions, school cycles, and demographic factors on influenza transmission. METHODS AND FINDINGS: We used influenza surveillance data compiled by the Mexican Institute for Social Security, representing 40% of the population, to study patterns in influenza-like illness (ILIs hospitalizations, deaths, and case-fatality rate by pandemic wave and geographical region. We also estimated the reproduction number (R on the basis of the growth rate of daily cases, and used a transmission model to evaluate the effectiveness of mitigation strategies initiated during the spring pandemic wave. A total of 117,626 ILI cases were identified during April-December 2009, of which 30.6% were tested for influenza, and 23.3% were positive for the influenza A/H1N1 pandemic virus. A three-wave pandemic profile was identified, with an initial wave in April-May (Mexico City area, a second wave in June-July (southeastern states, and a geographically widespread third wave in August-December. The median age of laboratory confirmed ILI cases was ∼ 18 years overall and increased to ∼ 31 years during autumn (p<0.0001. The case-fatality ratio among ILI cases was 1.2% overall, and highest (5.5% among people over 60 years. The regional R estimates were 1.8-2.1, 1.6-1.9, and 1.2-1.3 for the spring, summer, and fall waves, respectively. We estimate that the 18-day period of mandatory school closures and other social distancing measures implemented in the greater Mexico City area was associated with a 29%-37% reduction in influenza transmission in spring 2009. In addition, an increase in R was observed in late May and early June in the southeast states, after mandatory school

  9. Clinical profile and outcome of critically ill pregnant females with H1N1 influenza

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    Minal Shastri

    2016-12-01

    Full Text Available Background Record based review of the 2009 H1N1 Influenza pandemic suggests that pregnant women are at higher risk for hospitalization and death due to H1N1 Influenza. Aims To study the clinical profile and outcome of critically ill pregnant females admitted in intensive care unit (ICU with real-time recombinant polymerase chain reaction (rRT-PCR proven positive H1N1 cases. Methods A retrospective record-review based study was conducted at Sir SayajiRao General Hospital (SSGH and Medical College, Vadodara on data of confirmed rRT-PCR H1N1 pregnant females admitted during the pandemics of 2010and 2015. Demographics, clinical profile and laboratory investigations were recorded and outcomes (survived or expired were analysed. Results There were a total of 20 H1N1 positive pregnant females requiring ICU admission. With equal demographic distribution among rural and urban population, cough and fever were the most common presenting complaints. 65 per cent were in third trimester, the subgroup which also had the highest mortality. Mean days from onset until presentation was 5.05 days. 12 (60 per cent patients’ required invasive mode of ventilation and all died. Average hospital stay was 7 days. Foetus had favourable outcome in patients who recovered from H1N1 acute illness. Conclusion Pregnant females in our study had 60 per cent mortality. Thus, awareness, early diagnosis and treatment should be provided to them. Guidelines, policy changes and government protocols are required specifically for pregnant females with H1N1 Influenza A infection. Our study was an observational study and comparisons with non-pregnant females were not done, conclusions applicable to entire pregnant population was not derived.

  10. EFEKTIVITAS PEMBERIAN EKSTRAK SARANG SEMUT (Myrmecodia .sp TERHADAP RESPON ANTIBODY AVIAN INFLUENZA SUBTIPE H5N1

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    Ertika Fitri Lisnanti

    2017-11-01

    Full Text Available Abstract Avian influenza is a kind of contagious disease which can spread not only to other poultry but also to the human (zoonosis. Avian influeza becomes world issue when the human can effect the death. Sarang Semut plant (Myrmecodia .sp which has much anti-oxidant and imunostimulant can increase immunity. Imunostimulant will help and protect body cells well. The increasing of cellular immunity will help the cell attack the AI virus and increase the work of avian influenza vaccine. Therefore, this research is done to know the influence of sarang semut extract toward poultry’s anti-body of avian influenza H5N1. This research using experimental method. The design used is RAL factorial. Factor I: the addition of sarang semut extract amounted 5mgs/kgs BB, 10 mg/kg BB, 15 mg/kg BB and Factor II: the length of giving sarang semut extract, namely:  3 days, 5 days, and 7 days. The result of this research was analyzed using variance analysis (ANOVA followed by BNT. The result of serology examination shows that in adding sarang semut extract showing the significant different in each experiment, but not showing the significant different in the time given. The more increasing of the anti-body titer average and more decreasing CV can give  the more optimal protection for H5N1 virus attack. The recomended result on this research average titer and CV is giving sarang semut extract by 10 mgs/kgs BB dosage.

  11. Protective efficacy of Newcastle disease virus expressing soluble trimeric hemagglutinin against highly pathogenic H5N1 influenza in chickens and mice.

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    Lisette A H M Cornelissen

    Full Text Available BACKGROUND: Highly pathogenic avian influenza virus (HPAIV causes a highly contagious often fatal disease in poultry, resulting in significant economic losses in the poultry industry. HPAIV H5N1 also poses a major public health threat as it can be transmitted directly from infected poultry to humans. One effective way to combat avian influenza with pandemic potential is through the vaccination of poultry. Several live vaccines based on attenuated Newcastle disease virus (NDV that express influenza hemagglutinin (HA have been developed to protect chickens or mammalian species against HPAIV. However, the zoonotic potential of NDV raises safety concerns regarding the use of live NDV recombinants, as the incorporation of a heterologous attachment protein may result in the generation of NDV with altered tropism and/or pathogenicity. METHODOLOGY/PRINCIPAL FINDINGS: In the present study we generated recombinant NDVs expressing either full length, membrane-anchored HA of the H5 subtype (NDV-H5 or a soluble trimeric form thereof (NDV-sH5(3. A single intramuscular immunization with NDV-sH5(3 or NDV-H5 fully protected chickens against disease after a lethal challenge with H5N1 and reduced levels of virus shedding in tracheal and cloacal swabs. NDV-sH5(3 was less protective than NDV-H5 (50% vs 80% protection when administered via the respiratory tract. The NDV-sH5(3 was ineffective in mice, regardless of whether administered oculonasally or intramuscularly. In this species, NDV-H5 induced protective immunity against HPAIV H5N1, but only after oculonasal administration, despite the poor H5-specific serum antibody response it elicited. CONCLUSIONS/SIGNIFICANCE: Although NDV expressing membrane anchored H5 in general provided better protection than its counterpart expressing soluble H5, chickens could be fully protected against a lethal challenge with H5N1 by using the latter NDV vector. This study thus provides proof of concept for the use of recombinant

  12. Experimental infection of swans and geese with highly pathogenic avian influenza virus (H5N1) of Asian lineage.

    Science.gov (United States)

    Brown, Justin D; Stallknecht, David E; Swayne, David E

    2008-01-01

    The role of wild birds in the epidemiology of the Asian lineage highly pathogenic avian influenza (HPAI) virus subtype H5N1 epizootic and their contribution to the spread of the responsible viruses in Eurasia and Africa are unclear. To better understand the potential role of swans and geese in the epidemiology of this virus, we infected 4 species of swans and 2 species of geese with an HPAI virus of Asian lineage recovered from a whooper swan in Mongolia in 2005, A/whooper swan/Mongolia/244/2005 (H5N1). The highest mortality rates were observed in swans, and species-related differences in clinical illness and viral shedding were evident. These results suggest that the potential for HPAI (H5N1) viral shedding and the movement of infected birds may be species-dependent and can help explain observed deaths associated with HPAI (H5N1) infection in anseriforms in Eurasia.

  13. Genetic Characterization of H1N1 and H1N2 Influenza A Viruses Circulating in Ontario Pigs in 2012.

    Science.gov (United States)

    Grgić, Helena; Costa, Marcio; Friendship, Robert M; Carman, Susy; Nagy, Éva; Poljak, Zvonimir

    2015-01-01

    The objective of this study was to characterize H1N1 and H1N2 influenza A virus isolates detected during outbreaks of respiratory disease in pig herds in Ontario (Canada) in 2012. Six influenza viruses were included in analysis using full genome sequencing based on the 454 platform. In five H1N1 isolates, all eight segments were genetically related to 2009 pandemic virus (A(H1N1)pdm09). One H1N2 isolate had hemagglutinin (HA), polymerase A (PA) and non-structural (NS) genes closely related to A(H1N1)pdm09, and neuraminidase (NA), matrix (M), polymerase B1 (PB1), polymerase B2 (PB2), and nucleoprotein (NP) genes originating from a triple-reassortant H3N2 virus (tr H3N2). The HA gene of five Ontario H1 isolates exhibited high identity of 99% with the human A(H1N1)pdm09 [A/Mexico/InDRE4487/09] from Mexico, while one Ontario H1N1 isolate had only 96.9% identity with this Mexican virus. Each of the five Ontario H1N1 viruses had between one and four amino acid (aa) changes within five antigenic sites, while one Ontario H1N2 virus had two aa changes within two antigenic sites. Such aa changes in antigenic sites could have an effect on antibody recognition and ultimately have implications for immunization practices. According to aa sequence analysis of the M2 protein, Ontario H1N1 and H1N2 viruses can be expected to offer resistance to adamantane derivatives, but not to neuraminidase inhibitors.

  14. Pathogenesis of Highly Pathogenic Avian Influenza (HPAI) A/turkey/Turkey/1/2005 H5N1 in Pekin ducks (Anas platyrhynchos) infected experimentally

    OpenAIRE

    Löndt , Brandon Z.; Nunez , Alejandro; Banks , Jill; Nili , Hassan; Johnson , Linda K; Alexander , Dennis

    2008-01-01

    Abstract Asian H5N1 (hereafter referred to as panzootic H5N1) highly pathogenic avian influenza (HPAI) virus has caused large numbers of deaths in both poultry and wild bird populations. Recent isolates of this virus have been reported to cause disease and death in commercial ducks, which has not been seen with other HPAI viruses. However, little is known about the dissemination of this H5N1 within the organs and the cause of death in infected ducks. Nineteen 4-week-old Pekin ducks...

  15. Coinfection with influenza A(H1N1)pdm09 and dengue virus in fatal cases.

    Science.gov (United States)

    Perdigão, Anne Carolinne Bezerra; Ramalho, Izabel Letícia Cavalcante; Guedes, Maria Izabel Florindo; Braga, Deborah Nunes Melo; Cavalcanti, Luciano Pamplona Góes; Melo, Maria Elisabeth Lisboa de; Araújo, Rafael Montenegro de Carvalho; Lima, Elza Gadelha; Silva, Luciene Alexandre Bié da; Araújo, Lia de Carvalho; Araújo, Fernanda Montenegro de Carvalho

    2016-09-01

    We report on four patients with fatal influenza A(H1N1)pdm09 and dengue virus coinfections. Clinical, necropsy and histopathologic findings presented in all cases were characteristic of influenza-dengue coinfections, and all were laboratory-confirmed for both infections. The possibility of influenza and dengue coinfection should be considered in locations where these two viruses' epidemic periods coincide to avoid fatal outcomes. Dengue is a mosquito-borne viral infection caused by one of the four dengue viruses (DENV-1 to 4). Each of these viruses is capable of causing nonspecific febrile illnesses, classic dengue fever and dengue haemorrhagic fever (Gubler 1998). As a result, dengue is often difficult to diagnose clinically, especially because peak dengue season often coincides with that of other common febrile illnesses in tropical regions (Chacon et al. 2015). In April 2009, a new virus, influenza A/H1N1/pandemic (FluA/H1N1/09pdm), caused a severe outbreak in Mexico. The virus quickly spread throughout the world, and in June 2009, the World Health Organization declared a pandemic (WHO 2010). In Brazil, the first laboratory confirmed case of FluA/H1N1/09pdm was in July 2009 (Pires Neto et al. 2013). The state of Ceará, in Northeast Brazil, is a dengue endemic area. In this state, the virus influenza A(H1N1)pdm09 has circulated since 2009, and through the first half of 2012, 11 deaths caused by the virus were confirmed (Pires Neto et al. 2013). The influenza and dengue seasons in Ceará overlap, which led to diagnostic difficulties. We report four cases of laboratory-confirmed coinfection of deadly influenza A(H1N1)pdm09 with DENV, which occurred during the dengue and influenza season in 2012 and 2013 in Ceará.

  16. Coinfection with influenza A(H1N1pdm09 and dengue virus in fatal cases

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    Anne Carolinne Bezerra Perdigão

    2016-01-01

    Full Text Available Abstract We report on four patients with fatal influenza A(H1N1pdm09 and dengue virus coinfections. Clinical, necropsy and histopathologic findings presented in all cases were characteristic of influenza-dengue coinfections, and all were laboratory-confirmed for both infections. The possibility of influenza and dengue coinfection should be considered in locations where these two viruses’ epidemic periods coincide to avoid fatal outcomes. Dengue is a mosquito-borne viral infection caused by one of the four dengue viruses (DENV-1 to 4. Each of these viruses is capable of causing nonspecific febrile illnesses, classic dengue fever and dengue haemorrhagic fever (Gubler 1998. As a result, dengue is often difficult to diagnose clinically, especially because peak dengue season often coincides with that of other common febrile illnesses in tropical regions (Chacon et al. 2015. In April 2009, a new virus, influenza A/H1N1/pandemic (FluA/H1N1/09pdm, caused a severe outbreak in Mexico. The virus quickly spread throughout the world, and in June 2009, the World Health Organization declared a pandemic (WHO 2010. In Brazil, the first laboratory confirmed case of FluA/H1N1/09pdm was in July 2009 (Pires Neto et al. 2013. The state of Ceará, in Northeast Brazil, is a dengue endemic area. In this state, the virus influenza A(H1N1pdm09 has circulated since 2009, and through the first half of 2012, 11 deaths caused by the virus were confirmed (Pires Neto et al. 2013. The influenza and dengue seasons in Ceará overlap, which led to diagnostic difficulties. We report four cases of laboratory-confirmed coinfection of deadly influenza A(H1N1pdm09 with DENV, which occurred during the dengue and influenza season in 2012 and 2013 in Ceará.

  17. Outbreak of H3N2 influenza at a US military base in Djibouti during the H1N1 pandemic of 2009.

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    Michael T Cosby

    Full Text Available BACKGROUND: Influenza pandemics have significant operational impact on deployed military personnel working in areas throughout the world. The US Department of Defense global influenza-like illness (ILI surveillance network serves an important role in establishing baseline trends and can be leveraged to respond to outbreaks of respiratory illness. OBJECTIVE: We identified and characterized an operationally unique outbreak of H3N2 influenza at Camp Lemonnier, Djibouti occurring simultaneously with the H1N1 pandemic of 2009 [A(H1N1pdm09]. METHODS: Enhanced surveillance for ILI was conducted at Camp Lemonnier in response to local reports of a possible outbreak during the A(H1N1pdm09 pandemic. Samples were collected from consenting patients presenting with ILI (utilizing a modified case definition and who completed a case report form. Samples were cultured and analyzed using standard real-time reverse transcriptase PCR (rt-RT-PCR methodology and sequenced genetic material was phylogenetically compared to other published strains. RESULTS: rt-RT-PCR and DNA sequencing revealed that 25 (78% of the 32 clinical samples collected were seasonal H3N2 and only 2 (6% were A(H1N1pdm09 influenza. The highest incidence of H3N2 occurred during the month of May and 80% of these were active duty military personnel. Phylogenetic analysis revealed that sequenced H3N2 strains were genetically similar to 2009 strains from the United States of America, Australia, and South east Asia. CONCLUSIONS: This outbreak highlights challenges in the investigation of influenza among deployed military populations and corroborates the public health importance of maintaining surveillance systems for ILI that can be enhanced locally when needed.

  18. Supply of neuraminidase inhibitors related to reduced influenza A (H1N1) mortality during the 2009-2010 H1N1 pandemic: summary of an ecological study.

    Science.gov (United States)

    Miller, Paula E; Rambachan, Aksharananda; Hubbard, Roderick J; Li, Jiabai; Meyer, Alison E; Stephens, Peter; Mounts, Anthony W; Rolfes, Melissa A; Penn, Charles R

    2013-09-01

    When the influenza A (H1N1) pandemic spread across the globe from April 2009 to August 2010, many WHO Member States used antiviral drugs, specifically neuraminidase inhibitors (NAIs) oseltamivir and zanamivir, to treat influenza patients in critical condition. Antivirals have been found to be effective in reducing severity and duration of influenza illness, and likely reduce morbidity; however, it is unclear whether NAIs used during the pandemic reduced H1N1 mortality. To assess the association between antivirals and influenza mortality, at an ecologic level, country-level data on supply of oseltamivir and zanamivir were compared to laboratory-confirmed H1N1 deaths (per 100 000 people) from July 2009 to August 2010 in 42 WHO Member States. From this analysis, it was found that each 10% increase in kilograms of oseltamivir, per 100 000 people, was associated with a 1·6% reduction in H1N1 mortality over the pandemic period [relative rate (RR) = 0·84 per log increase in oseltamivir supply]. Each 10% increase in kilogram of active zanamivir, per 100 000, was associated with a 0·3% reduction in H1N1 mortality (RR = 0·97 per log increase). While limitations exist in the inference that can be drawn from an ecologic evaluation, this analysis offers evidence of a protective relationship between antiviral drug supply and influenza mortality and supports a role for influenza antiviral use in future pandemics. This article summarises the original study described previously, which can be accessed through the following citation: Miller PE, Rambachan A, Hubbard RJ, Li J, Meyer AE, et al. (2012) Supply of Neuraminidase Inhibitors Related to Reduced Influenza A (H1N1) Mortality during the 2009-2010 H1N1 Pandemic: An Ecological Study. PLoS ONE 7(9): e43491. © 2013 Blackwell Publishing Ltd.

  19. An Analysis of 332 Fatalities Infected with Pandemic 2009 Influenza A (H1N1) in Argentina

    Science.gov (United States)

    Balanzat, Ana M.; Hertlein, Christian; Apezteguia, Carlos; Bonvehi, Pablo; Cámera, Luis; Gentile, Angela; Rizzo, Oscar; Gómez-Carrillo, Manuel; Coronado, Fatima; Azziz-Baumgartner, Eduardo; Chávez, Pollyanna R.; Widdowson, Marc-Alain

    2012-01-01

    Background The apparent high number of deaths in Argentina during the 2009 pandemic led to concern that the influenza A H1N1pdm disease was different there. We report the characteristics and risk factors for influenza A H1N1pdm fatalities. Methods We identified laboratory-confirmed influenza A H1N1pdm fatalities occurring during June-July 2009. Physicians abstracted data on age, sex, time of onset of illness, medical history, clinical presentation at admission, laboratory, treatment, and outcomes using standardize questionnaires. We explored the characteristics of fatalities according to their age and risk group. Results Of 332 influenza A H1N1pdm fatalities, 226 (68%) were among persons aged Argentina, though timeliness of antiviral treatment improved during the pandemic. PMID:22506006

  20. Seasonal patterns in human A (H5N1 virus infection: analysis of global cases.

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    Maya B Mathur

    Full Text Available Human cases of highly pathogenic avian influenza (HPAI A (H5N1 have high mortality. Despite abundant data on seasonal patterns in influenza epidemics, it is unknown whether similar patterns exist for human HPAI H5N1 cases worldwide. Such knowledge could help decrease avian-to-human transmission through increased prevention and control activities during peak periods.We performed a systematic search of published human HPAI H5N1 cases to date, collecting month, year, country, season, hemisphere, and climate data. We used negative binomial regression to predict changes in case incidence as a function of season. To investigate hemisphere as a potential moderator, we used AIC and the likelihood-ratio test to compare the season-only model to nested models including a main effect or interaction with hemisphere. Finally, we visually assessed replication of seasonal patterns across climate groups based on the Köppen-Geiger climate classification.We identified 617 human cases (611 with complete seasonal data occurring in 15 countries in Southeast Asia, Africa, and the Middle East. Case occurrence was much higher in winter (n = 285, p = 0.03 than summer (n = 64, and the winter peak occurred across diverse climate groups. There was no significant interaction between hemisphere and season.Across diverse climates, HPAI H5N1 virus infection in humans increases significantly in winter. This is consistent with increased poultry outbreaks and HPAI H5N1 virus transmission during cold and dry conditions. Prioritizing prevention and control activities among poultry and focusing public health messaging to reduce poultry exposures during winter months may help to reduce zoonotic transmission of HPAI H5N1 virus in resource-limited settings.

  1. Efficacy of a pandemic (H1N1) 2009 virus vaccine in pigs against the pandemic influenza virus is superior to commercially available swine influenza vaccines.

    Science.gov (United States)

    Loeffen, W L A; Stockhofe, N; Weesendorp, E; van Zoelen-Bos, D; Heutink, R; Quak, S; Goovaerts, D; Heldens, J G M; Maas, R; Moormann, R J; Koch, G

    2011-09-28

    In April 2009 a new influenza A/H1N1 strain, currently named "pandemic (H1N1) influenza 2009" (H1N1v), started the first official pandemic in humans since 1968. Several incursions of this virus in pig herds have also been reported from all over the world. Vaccination of pigs may be an option to reduce exposure of human contacts with infected pigs, thereby preventing cross-species transfer, but also to protect pigs themselves, should this virus cause damage in the pig population. Three swine influenza vaccines, two of them commercially available and one experimental, were therefore tested and compared for their efficacy against an H1N1v challenge. One of the commercial vaccines is based on an American classical H1N1 influenza strain, the other is based on a European avian H1N1 influenza strain. The experimental vaccine is based on reassortant virus NYMC X179A (containing the hemagglutinin (HA) and neuraminidase (NA) genes of A/California/7/2009 (H1N1v) and the internal genes of A/Puerto Rico/8/34 (H1N1)). Excretion of infectious virus was reduced by 0.5-3 log(10) by the commercial vaccines, depending on vaccine and sample type. Both vaccines were able to reduce virus replication especially in the lower respiratory tract, with less pathological lesions in vaccinated and subsequently challenged pigs than in unvaccinated controls. In pigs vaccinated with the experimental vaccine, excretion levels of infectious virus in nasal and oropharyngeal swabs, were at or below 1 log(10)TCID(50) per swab and lasted for only 1 or 2 days. An inactivated vaccine containing the HA and NA of an H1N1v is able to protect pigs from an infection with H1N1v, whereas swine influenza vaccines that are currently available are of limited efficaciousness. Whether vaccination of pigs against H1N1v will become opportune remains to be seen and will depend on future evolution of this strain in the pig population. Close monitoring of the pig population, focussing on presence and evolution of

  2. Identification of TMPRSS2 as a Susceptibility Gene for Severe 2009 Pandemic A(H1N1) Influenza and A(H7N9) Influenza

    NARCIS (Netherlands)

    Cheng, Zhongshan; Zhou, Jie; To, Kelvin Kai-Wang; Chu, Hin; Li, Cun; Wang, Dong; Yang, Dong; Zheng, Shufa; Hao, Ke; Bosse, Yohan; Obeidat, Ma'en; Brandsma, Corry-Anke; Song, You-Qiang; Chen, Yu; Zheng, Bo-Jian; Li, Lanjuan; Yuen, Kwok-Yung

    2015-01-01

    The genetic predisposition to severe A(H1N1) 2009 (A[H1N1]pdm09) influenza was evaluated in 409 patients, including 162 cases with severe infection and 247 controls with mild infection. We prioritized candidate variants based on the result of a pilot genome-wide association study and a lung

  3. Role of domestic ducks in the emergence of a new genotype of highly pathogenic H5N1 avian influenza A viruses in Bangladesh.

    Science.gov (United States)

    Barman, Subrata; Marinova-Petkova, Atanaska; Hasan, M Kamrul; Akhtar, Sharmin; El-Shesheny, Rabeh; Turner, Jasmine Cm; Franks, John; Walker, David; Seiler, Jon; Friedman, Kimberly; Kercher, Lisa; Jeevan, Trushar; Darnell, Daniel; Kayali, Ghazi; Jones-Engel, Lisa; McKenzie, Pamela; Krauss, Scott; Webby, Richard J; Webster, Robert G; Feeroz, Mohammed M

    2017-08-09

    Highly pathogenic avian influenza H5N1 viruses were first isolated in Bangladesh in February 2007. Subsequently, clades 2.2.2, 2.3.4.2 and 2.3.2.1a were identified in Bangladesh, and our previous surveillance data revealed that by the end of 2014, the circulating viruses exclusively comprised clade 2.3.2.1a. We recently determined the status of circulating avian influenza viruses in Bangladesh by conducting surveillance of live poultry markets and waterfowl in wetland areas from February 2015 through February 2016. Until April 2015, clade 2.3.2.1a persisted without any change in genotype. However, in June 2015, we identified a new genotype of H5N1 viruses, clade 2.3.2.1a, which quickly became predominant. These newly emerged H5N1 viruses contained the hemagglutinin, neuraminidase and matrix genes of circulating 2.3.2.1a Bangladeshi H5N1 viruses and five other genes of low pathogenic Eurasian-lineage avian influenza A viruses. Some of these internal genes were closely related to those of low pathogenic viruses isolated from ducks in free-range farms and wild birds in a wetland region of northeastern Bangladesh, where commercially raised domestic ducks have frequent contact with migratory birds. These findings indicate that migratory birds of the Central Asian flyway and domestic ducks in the free-range farms in Tanguar haor-like wetlands played an important role in the emergence of this novel genotype of highly pathogenic H5N1 viruses.

  4. Influenza A (H1N1pdm09)-Related Critical Illness and Mortality in Mexico and Canada, 2014.

    Science.gov (United States)

    Dominguez-Cherit, Guillermo; De la Torre, Alethse; Rishu, Asgar; Pinto, Ruxandra; Ñamendys-Silva, Silvio A; Camacho-Ortiz, Adrián; Silva-Medina, Marco Antonio; Hernández-Cárdenas, Carmen; Martínez-Franco, Michel; Quesada-Sánchez, Alejandro; López-Gallegos, Guadalupe Celia; Mosqueda-Gómez, Juan L; Rivera-Martinez, Norma E; Campos-Calderón, Fernando; Rivero-Sigarroa, Eduardo; Hernández-Gilsoul, Thierry; Espinosa-Pérez, Lourdes; Macías, Alejandro E; Lue-Martínez, Dolores M; Buelna-Cano, Christian; Ramírez-García Luna, Ana-Sofía; Cruz-Ruiz, Nestor G; Poblano-Morales, Manuel; Molinar-Ramos, Fernando; Hernandez-Torre, Martin; León-Gutiérrez, Marco Antonio; Rosaldo-Abundis, Oscar; Baltazar-Torres, José Ángel; Stelfox, Henry T; Light, Bruce; Jouvet, Philippe; Reynolds, Steve; Hall, Richard; Shindo, Nikki; Daneman, Nick; Fowler, Robert A

    2016-10-01

    The 2009-2010 influenza A (H1N1pdm09) pandemic caused substantial morbidity and mortality among young patients; however, mortality estimates have been confounded by regional differences in eligibility criteria and inclusion of selected populations. In 2013-2014, H1N1pdm09 became North America's dominant seasonal influenza strain. Our objective was to compare the baseline characteristics, resources, and treatments with outcomes among critically ill patients with influenza A (H1N1pdm09) in Mexican and Canadian hospitals in 2014 using consistent eligibility criteria. Observational study and a survey of available healthcare setting resources. Twenty-one hospitals, 13 in Mexico and eight in Canada. Critically ill patients with confirmed H1N1pdm09 during 2013-2014 influenza season. None. The main outcome measures were 90-day mortality and independent predictors of mortality. Among 165 adult patients with H1N1pdm09-related critical illness between September 2013 and March 2014, mean age was 48.3 years, 64% were males, and nearly all influenza was community acquired. Patients were severely hypoxic (median PaO2-to-FIO2 ratio, 83 mm Hg), 97% received mechanical ventilation, with mean positive end-expiratory pressure of 14 cm H2O at the onset of critical illness and 26.7% received rescue oxygenation therapy with prone ventilation, extracorporeal life support, high-frequency oscillatory ventilation, or inhaled nitric oxide. At 90 days, mortality was 34.6% (13.9% in Canada vs 50.5% in Mexico, p Mexico (odds ratio, 7.76 [95% CI, 2.02-27.35]). ICUs in Canada generally had more beds, ventilators, healthcare personnel, and rescue oxygenation therapies. Influenza A (H1N1pdm09)-related critical illness still predominantly affects relatively young to middle-aged patients and is associated with severe hypoxemic respiratory failure. The local critical care system and available resources may be influential determinants of patient outcome.

  5. Genetic Characterization of H1N1 and H1N2 Influenza A Viruses Circulating in Ontario Pigs in 2012.

    Directory of Open Access Journals (Sweden)

    Helena Grgić

    Full Text Available The objective of this study was to characterize H1N1 and H1N2 influenza A virus isolates detected during outbreaks of respiratory disease in pig herds in Ontario (Canada in 2012. Six influenza viruses were included in analysis using full genome sequencing based on the 454 platform. In five H1N1 isolates, all eight segments were genetically related to 2009 pandemic virus (A(H1N1pdm09. One H1N2 isolate had hemagglutinin (HA, polymerase A (PA and non-structural (NS genes closely related to A(H1N1pdm09, and neuraminidase (NA, matrix (M, polymerase B1 (PB1, polymerase B2 (PB2, and nucleoprotein (NP genes originating from a triple-reassortant H3N2 virus (tr H3N2. The HA gene of five Ontario H1 isolates exhibited high identity of 99% with the human A(H1N1pdm09 [A/Mexico/InDRE4487/09] from Mexico, while one Ontario H1N1 isolate had only 96.9% identity with this Mexican virus. Each of the five Ontario H1N1 viruses had between one and four amino acid (aa changes within five antigenic sites, while one Ontario H1N2 virus had two aa changes within two antigenic sites. Such aa changes in antigenic sites could have an effect on antibody recognition and ultimately have implications for immunization practices. According to aa sequence analysis of the M2 protein, Ontario H1N1 and H1N2 viruses can be expected to offer resistance to adamantane derivatives, but not to neuraminidase inhibitors.

  6. Genetic characterization of highly pathogenic avian influenza A H5N8 viruses isolated from wild birds in Egypt.

    Science.gov (United States)

    Kandeil, Ahmed; Kayed, Ahmed; Moatasim, Yassmin; Webby, Richard J; McKenzie, Pamela P; Kayali, Ghazi; Ali, Mohamed A

    2017-07-01

    A newly emerged H5N8 influenza virus was isolated from green-winged teal in Egypt during December 2016. In this study, we provide a detailed characterization of full genomes of Egyptian H5N8 viruses and some virological features. Genetic analysis demonstrated that the Egyptian H5N8 viruses are highly pathogenic avian influenza viruses. Phylogenetic analysis revealed that the genome of the Egyptian H5N8 viruses was related to recently characterized reassortant H5N8 viruses of clade 2.3.4.4 isolated from different Eurasian countries. Multiple peculiar mutations were characterized in the Egyptian H5N8 viruses, which probably permits transmission and virulence of these viruses in mammals. The Egyptian H5N8 viruses preferentially bound to avian-like receptors rather than human-like receptors. Also, the Egyptian H5N8 viruses were fully sensitive to amantadine and neuraminidase inhibitors. Chicken sera raised against commercial inactivated avian influenza-H5 vaccines showed no or very low reactivity with the currently characterized H5N8 viruses in agreement with the genetic dissimilarity. Surveillance of avian influenza in waterfowl provides early warning of specific threats to poultry and human health and hence should be continued.

  7. D701N mutation in the PB2 protein contributes to the pathogenicity of H5N1 avian influenza viruses but not transmissibility in guinea pigs

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    Peirong eJiao

    2014-11-01

    Full Text Available H5N1 highly pathogenic avian influenza virus (HPAIV of clade 2.3.2 has been circulating in waterfowl in Southern China since 2003. Our previous studies showed that certain H5N1 HPAIV isolates within clade 2.3.2 from Southern China had high pathogenicity in different birds. Guinea pigs have been successfully used as models to evaluate the transmissibility of AIVs and other species of influenza viruses in mammalian hosts. However, few studies have reported pathogenicity and transmissibility of H5N1 HPAIVs of this clade in guinea pigs. In this study, we selected an H5N1 HPAIV isolate, A/duck/Guangdong/357/2008, to investigate the pathogenicity and transmissibility of the virus in guinea pigs. The virus had high pathogenicity in mice; additionally, it only replicated in some tissues of the guinea pigs without production of clinical signs, but was transmissible among guinea pigs. Interestingly, virus isolates from co-caged guinea pigs had the D701N mutation in the PB2 protein. These mutant viruses showed higher pathogenicity in mice and higher replication capability in guinea pigs but did not demonstrate enhanced the transmissibility among guinea pigs. These findings indicate the transmission of the H5N1 virus between mammals could induce virus mutations, and the mutant viruses might have higher pathogenicity in mammals without higher transmissibility. Therefore, the continued evaluation of the pathogenicity and transmissibility of avian influenza virus (AIVs in mammals is critical to the understanding of the evolutionary characteristics of AIVs and the emergence of potential pandemic strains.

  8. Avian Influenza H5N1 and the Wild Bird Trade in Hanoi, Vietnam

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    F. Brooks-Moizer

    2009-06-01

    Full Text Available Wildlife trade and emerging infectious diseases pose significant threats to human and animal health and global biodiversity. Legal and illegal trade in domestic and wild birds has played a significant role in the global spread of highly pathogenic avian influenza H5N1, which has killed more than 240 people, many millions of poultry, and an unknown number of wild birds and mammals, including endangered species, since 2003. This 2007 study provides evidence for a significant decline in the scale of the wild bird trade in Hanoi since previous surveys in 2000 (39.7% decline and 2003 (74.1% decline. We attribute this to the enforcement of Vietnam's Law 169/2005/QD UBND, introduced in 2005, which prohibits the movement and sale of wild and ornamental birds in cities. Nevertheless, 91.3% (21/23 of bird vendors perceived no risk of H5N1 infection from their birds, and the trade continues, albeit at reduced levels, in open market shops. These findings highlight the importance of continued law enforcement to maintain this trade reduction and the associated benefits to human and animal health and biodiversity conservation.

  9. High burden of non-influenza viruses in influenza-like illness in the early weeks of H1N1v epidemic in France.

    Directory of Open Access Journals (Sweden)

    Nathalie Schnepf

    Full Text Available BACKGROUND: Influenza-like illness (ILI may be caused by a variety of pathogens. Clinical observations are of little help to recognise myxovirus infection and implement appropriate prevention measures. The limited use of molecular tools underestimates the role of other common pathogens. OBJECTIVES: During the early weeks of the 2009-2010 flu pandemic, a clinical and virological survey was conducted in adult and paediatric patients with ILI referred to two French University hospitals in Paris and Tours. Aims were to investigate the different pathogens involved in ILI and describe the associated symptoms. METHODS: H1N1v pandemic influenza diagnosis was performed with real time RT-PCR assay. Other viral aetiologies were investigated by the molecular multiplex assay RespiFinder19®. Clinical data were collected prospectively by physicians using a standard questionnaire. RESULTS: From week 35 to 44, endonasal swabs were collected in 413 patients. Overall, 68 samples (16.5% were positive for H1N1v. In 13 of them, other respiratory pathogens were also detected. Among H1N1v negative samples, 213 (61.9% were positive for various respiratory agents, 190 in single infections and 23 in mixed infections. The most prevalent viruses in H1N1v negative single infections were rhinovirus (62.6%, followed by parainfluenza viruses (24.2% and adenovirus (5.3%. 70.6% of H1N1v cases were identified in patients under 40 years and none after 65 years. There was no difference between clinical symptoms observed in patients infected with H1N1v or with other pathogens. CONCLUSION: Our results highlight the high frequency of non-influenza viruses involved in ILI during the pre-epidemic period of a flu alert and the lack of specific clinical signs associated with influenza infections. Rapid diagnostic screening of a large panel of respiratory pathogens may be critical to define and survey the epidemic situation and to provide critical information for patient management.

  10. Spatial and temporal characteristics of the 2009 A/H1N1 influenza pandemic in Peru.

    Science.gov (United States)

    Chowell, Gerardo; Viboud, Cécile; Munayco, Cesar V; Gómez, Jorge; Simonsen, Lone; Miller, Mark A; Tamerius, James; Fiestas, Victor; Halsey, Eric S; Laguna-Torres, Victor A

    2011-01-01

    Highly refined surveillance data on the 2009 A/H1N1 influenza pandemic are crucial to quantify the spatial and temporal characteristics of the pandemic. There is little information about the spatial-temporal dynamics of pandemic influenza in South America. Here we provide a quantitative description of the age-specific morbidity pandemic patterns across administrative areas of Peru. We used daily cases of influenza-like-illness, tests for A/H1N1 influenza virus infections, and laboratory-confirmed A/H1N1 influenza cases reported to the epidemiological surveillance system of Peru's Ministry of Health from May 1 to December 31, 2009. We analyzed the geographic spread of the pandemic waves and their association with the winter school vacation period, demographic factors, and absolute humidity. We also estimated the reproduction number and quantified the association between the winter school vacation period and the age distribution of cases. The national pandemic curve revealed a bimodal winter pandemic wave, with the first peak limited to school age children in the Lima metropolitan area, and the second peak more geographically widespread. The reproduction number was estimated at 1.6-2.2 for the Lima metropolitan area and 1.3-1.5 in the rest of Peru. We found a significant association between the timing of the school vacation period and changes in the age distribution of cases, while earlier pandemic onset was correlated with large population size. By contrast there was no association between pandemic dynamics and absolute humidity. Our results indicate substantial spatial variation in pandemic patterns across Peru, with two pandemic waves of varying timing and impact by age and region. Moreover, the Peru data suggest a hierarchical transmission pattern of pandemic influenza A/H1N1 driven by large population centers. The higher reproduction number of the first pandemic wave could be explained by high contact rates among school-age children, the age group most affected

  11. Spatial and Temporal Characteristics of the 2009 A/H1N1 Influenza Pandemic in Peru

    Science.gov (United States)

    Chowell, Gerardo; Viboud, Cécile; Munayco, Cesar V.; Gómez, Jorge; Simonsen, Lone; Miller, Mark A.; Tamerius, James; Fiestas, Victor; Halsey, Eric S.; Laguna-Torres, Victor A.

    2011-01-01

    Background Highly refined surveillance data on the 2009 A/H1N1 influenza pandemic are crucial to quantify the spatial and temporal characteristics of the pandemic. There is little information about the spatial-temporal dynamics of pandemic influenza in South America. Here we provide a quantitative description of the age-specific morbidity pandemic patterns across administrative areas of Peru. Methods We used daily cases of influenza-like-illness, tests for A/H1N1 influenza virus infections, and laboratory-confirmed A/H1N1 influenza cases reported to the epidemiological surveillance system of Peru's Ministry of Health from May 1 to December 31, 2009. We analyzed the geographic spread of the pandemic waves and their association with the winter school vacation period, demographic factors, and absolute humidity. We also estimated the reproduction number and quantified the association between the winter school vacation period and the age distribution of cases. Results The national pandemic curve revealed a bimodal winter pandemic wave, with the first peak limited to school age children in the Lima metropolitan area, and the second peak more geographically widespread. The reproduction number was estimated at 1.6–2.2 for the Lima metropolitan area and 1.3–1.5 in the rest of Peru. We found a significant association between the timing of the school vacation period and changes in the age distribution of cases, while earlier pandemic onset was correlated with large population size. By contrast there was no association between pandemic dynamics and absolute humidity. Conclusions Our results indicate substantial spatial variation in pandemic patterns across Peru, with two pandemic waves of varying timing and impact by age and region. Moreover, the Peru data suggest a hierarchical transmission pattern of pandemic influenza A/H1N1 driven by large population centers. The higher reproduction number of the first pandemic wave could be explained by high contact rates among school

  12. Exploring contacts facilitating transmission of influenza A(H5N1) virus between poultry farms in West Java, Indonesia

    NARCIS (Netherlands)

    Wibawa, Hendra; Karo-Karo, Desniwaty; Pribadi, Eko Sugeng; Bouma, Annemarie; Bodewes, Rogier; Vernooij, Hans; Diyantoro,; Sugama, Agus; Muljono, David H.; Koch, Guus; Tjatur Rasa, Fadjar Sumping; Stegeman, Arjan

    2018-01-01

    Highly pathogenic avian influenza virus (HPAIV) H5N1 has been reported in Asia, including Indonesia since 2003. Although several risk factors related to the HPAIV outbreaks in poultry in Indonesia have been identified, little is known of the contact structure of farms of different poultry production

  13. Production of inactivated influenza H5N1 vaccines from MDCK cells in serum-free medium.

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    Alan Yung-Chih Hu

    Full Text Available BACKGROUND: Highly pathogenic influenza viruses pose a constant threat which could lead to a global pandemic. Vaccination remains the principal measure to reduce morbidity and mortality from such pandemics. The availability and surging demand for pandemic vaccines needs to be addressed in the preparedness plans. This study presents an improved high-yield manufacturing process for the inactivated influenza H5N1 vaccines using Madin-Darby canine kidney (MDCK cells grown in a serum-free (SF medium microcarrier cell culture system. PRINCIPAL FINDING: The current study has evaluated the performance of cell adaptation switched from serum-containing (SC medium to several commercial SF media. The selected SF medium was further evaluated in various bioreactor culture systems for process scale-up evaluation. No significant difference was found in the cell growth in different sizes of bioreactors studied. In the 7.5 L bioreactor runs, the cell concentration reached to 2.3 × 10(6 cells/mL after 5 days. The maximum virus titers of 1024 Hemagglutinin (HA units/50 µL and 7.1 ± 0.3 × 10(8 pfu/mL were obtained after 3 days infection. The concentration of HA antigen as determined by SRID was found to be 14.1 µg/mL which was higher than those obtained from the SC medium. A mouse immunogenicity study showed that the formalin-inactivated purified SF vaccine candidate formulated with alum adjuvant could induce protective level of virus neutralization titers similar to those obtained from the SC medium. In addition, the H5N1 viruses produced from either SC or SF media showed the same antigenic reactivity with the NIBRG14 standard antisera. CONCLUSIONS: The advantages of this SF cell-based manufacturing process could reduce the animal serum contamination, the cost and lot-to-lot variation of SC medium production. This study provides useful information to manufacturers that are planning to use SF medium for cell-based influenza vaccine production.

  14. Severe pandemic 2009 H1N1 influenza disease due to pathogenic immune complexes

    Science.gov (United States)

    Monsalvo, Ana Clara; Batalle, Juan P.; Lopez, M. Florencia; Krause, Jens C.; Klemenc, Jennifer; Zea, Johanna; Maskin, Bernardo; Bugna, Jimena; Rubinstein, Carlos; Aguilar, Leandro; Dalurzo, Liliana; Libster, Romina; Savy, Vilma; Baumeister, Elsa; Aguilar, Liliana; Cabral, Graciela; Font, Julia; Solari, Liliana; Weller, Kevin P.; Johnson, Joyce; Echavarria, Marcela; Edwards, Kathryn M.; Chappell, James D.; Crowe, James E.; Williams, John V.; Melendi, Guillermina A.; Polack, Fernando P.

    2010-01-01

    Pandemic influenza viruses often cause severe disease in middle-aged adults without preexistent co-morbidities. The mechanism of illness associated with severe disease in this age group is not well understood1–10. Here, we demonstrate preexisting serum antibody that cross-reacts with, but does not protect against 2009 H1N1 influenza virus in middle-aged adults. Non-protective antibody is associated with immune complex(IC)-mediated disease after infection. High titers of serum antibody of low avidity for H1-2009 antigen, and low avidity pulmonary ICs against the same protein were detected in severely ill patients. Moreover, C4d deposition - a sensitive marker of complement activation mediated by ICs- was present in lung sections of fatal cases. Archived lung sections from adults with confirmed fatal influenza 1957 H2N2 infection revealed a similar mechanism of illness. These observations provide a novel biological mechanism for the unusual age distribution of severe cases during influenza pandemics. PMID:21131958

  15. Case of seasonal reassortant A(H1N2) influenza virus infection, the Netherlands, March 2018.

    NARCIS (Netherlands)

    Meijer, A.; Swaan, C.M.; Voerknecht, M.; Jusic, E.; Brink, S. van den; Wijsman, L.A.; Voordouw, B.C.G.; Donker, G.A.; Sleven, J.; Dorigo-Zetsma, W.W.; Svraka, S.; Boven, M. van; Haverkate, M.R.; Timen, A.; Dissel, J.T. van; Koopmans, M.P.G.; Besteboer, T.M.; Fouchier, R.A.M.

    2018-01-01

    A seasonal reassortant A(H1N2) influenza virus harbouring genome segments from seasonal influenza viruses A(H1N1)pdm09 (HA and NS) and A(H3N2) (PB2, PB1, PA, NP, NA and M) was identified in March 2018 in a 19-months-old patient with influenza-like illness (ILI) who presented to a general

  16. Case of seasonal reassortant A(H1N2) influenza virus infection, the Netherlands, March 2018.

    NARCIS (Netherlands)

    Meijer, Adam; Swaan, Corien M; Voerknecht, Martin; Jusic, Edin; van den Brink, Sharon; Wijsman, Lisa A; Voordouw, Bettie Cg; Donker, Gé A; Sleven, Jacqueline; Dorigo-Zetsma, Wendelien W; Svraka, Sanela; van Boven, Michiel; Haverkate, Manon R; Timen, Aura; van Dissel, Jaap T; Koopmans, Marion Pg; Bestebroer, Theo M; Fouchier, Ron Am

    A seasonal reassortant A(H1N2) influenza virus harbouring genome segments from seasonal influenza viruses A(H1N1)pdm09 (HA and NS) and A(H3N2) (PB2, PB1, PA, NP, NA and M) was identified in March 2018 in a 19-months-old patient with influenza-like illness (ILI) who presented to a general

  17. Victims and vectors: highly pathogenic avian influenza H5N1 and the ecology of wild birds

    Science.gov (United States)

    Takekawa, John Y.; Prosser, Diann J.; Newman, Scott H.; Muzaffar, Sabir Bin; Hill, Nichola J.; Yan, Baoping; Xiao, Xiangming; Lei, Fumin; Li, Tianxian; Schwarzbach, Steven E.; Howell, Judd A.

    2010-01-01

    The emergence of highly pathogenic avian influenza (HPAI) viruses has raised concerns about the role of wild birds in the spread and persistence of the disease. In 2005, an outbreak of the highly pathogenic subtype H5N1 killed more than 6,000 wild waterbirds at Qinghai Lake, China. Outbreaks have continued to periodically occur in wild birds at Qinghai Lake and elsewhere in Central China and Mongolia. This region has few poultry but is a major migration and breeding area for waterbirds in the Central Asian Flyway, although relatively little is known about migratory movements of different species and connectivity of their wetland habitats. The scientific debate has focused on the role of waterbirds in the epidemiology, maintenance and spread of HPAI H5N1: to what extent are they victims affected by the disease, or vectors that have a role in disease transmission? In this review, we summarise the current knowledge of wild bird involvement in the ecology of HPAI H5N1. Specifically, we present details on: (1) origin of HPAI H5N1; (2) waterbirds as LPAI reservoirs and evolution into HPAI; (3) the role of waterbirds in virus spread and persistence; (4) key biogeographic regions of outbreak; and (5) applying an ecological research perspective to studying AIVs in wild waterbirds and their ecosystems.

  18. Radiologic Findings of Influenza A (H1N1) Pneumonia: Report of Two Cases

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Jin Kyoung; Ahn, Myeong Im; Jung, Jung Im; Han, Dae Hee; Park, Seog Hee; Park, Chan Kwon; Kim, Young Kyoon [Seoul St. Mary' s Hospital, Seoul (Korea, Republic of)

    2010-08-15

    Novel influenza A (H1N1) infection is a highly infectious disease, which has been rapidly spreading worldwide since it was first documented in March of 2009 in Mexico. We experienced and report two cases of Influenza A (H1N1) pneumonia, accompanied by chest radiographic and CT findings. The chest radiographs revealed diffuse haziness and extensive airspace consolidation, whereas the CT scans demonstrated multifocal areas of ground glass opacity and airspace consolidation with a CT halo sign.

  19. The Clinical Course of Late Diagnosed Fatal Cases of A (H1N1 Influenza in Poland 

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    Marta Rorat

    2013-06-01

    Full Text Available Introduction: The most frequent complication of A (H1N1 influenza and the leading cause of death was pneumonia with a primary viral or mixed viral and bacterial etiology. 182 patients had died because of a pandemic influenza in Poland by 31st July 2010.Material and Methods: A retrospective study of 6 fatal cases of pandemic influenza, aged 23-41, including 3 women, hospitalised between November 2009 and February 2011 in different Polish medical centres.Results: We present the clinical course of 6 late diagnosed cases of A (H1N1 influenza. All patients presented typical flu-like symptoms in the beginning. 4/6 patients had severe disease risk factors: pregnancy, arthritis, Wegener granulomatosis and obesity. All patients were seen by doctors, no one had received antiviral therapy, 4/5 were treated with antibiotics before they were hospitalized. One patient had nosocomial infection. Patients were admitted to the hospital on the 3rd to 8th day of the disease. They received oseltamivir treatment on the 4th to 9th day. All patients developed pneumonia complicated by acute respiratory distress syndrome. Death appeared between the 4th and 27th day after the onset of symptoms. Autopsies were performed in 5 cases and revealed haemorrhagic pneumonia in 2 patients.Conclusion: Delayed diagnosis and antiviral treatment initiation has a significant impact on mortality in A (H1N1 influenza. During the influenza epidemic, patients presenting typical symptoms should always be suspected of having influenza. Antiviral treatment has to be initiated immediately, especially ifthere are risk factors of severe disease.

  20. H1N1 influenza ('swine 'flu') in the paediatric ICU in South Africa

    African Journals Online (AJOL)

    Schoub B. Swine flu – implications for South Africa. Communicable Diseases Surveillance. Bulletin 2009;7(3):5-7. 5. Ahrens JO, Morrow BM, Argent AC. Influenza A(H1N1)pdm09 in critically ill children admitted to a paediatric intensive care unit, South Africa. S Afr J Crit Care 2015;31(1):4-7. 6. Cox CM, Blanton L, Dhara R, ...

  1. TNF, IL6, and IL1B Polymorphisms Are Associated with Severe Influenza A (H1N1) Virus Infection in the Mexican Population

    Science.gov (United States)

    García-Ramírez, Román Alejandro; Ramírez-Venegas, Alejandra; Quintana-Carrillo, Roger; Camarena, Ángel Eduardo; Falfán-Valencia, Ramcés; Mejía-Aranguré, Juan Manuel

    2015-01-01

    Background Hypercytokinemia is the main immunopathological mechanism contributing to a more severe clinical course in influenza A (H1N1) virus infections. Most patients infected with the influenza A (H1N1) pdm09 virus had increased systemic levels of pro-inflammatory cytokines; including interleukin IL-6, IL-8, and tumor necrosis factor-alpha (TNF-α). We propose that single-nucleotide polymorphisms (SNPs) in the promoter regions of pro-inflammatory genes are associated with the severity of influenza A (H1N1) pdm09 virus infection. Methods 145 patients with influenza A (H1N1) (pA/H1N1), 133 patients with influenza-like illness (ILI), and 360 asymptomatic healthy contacts (AHCs) were included. Eleven SNPs were genotyped in six genes (TNF, LT, IL1B, IL6, CCL1, and IL8) using real-time PCR; the ancestral genotype was used for comparison. Genotypes were correlated with 27 clinical severity variables. Ten cytokines (GM-CSF, TNF-α, IL-2, IL-1β, IL-6, IL-8, IFN-γ, IL-10, IL-5, and IL-4) were measured on a Luminex 100. Results The IL6 rs1818879 (GA) heterozygous genotype was associated with severe influenza A (H1N1) virus infection (odds ratio [OR] = 5.94, 95% confidence interval [CI] 3.05–11.56), and two IL1B SNPs, rs16944 AG and rs3136558 TC, were associated with a decreased risk of infection (OR = 0.52 and OR = 0.51, respectively). Genetic susceptibility was determined (pA/H1N1 vs. AHC): the LTA rs909253 TC heterozygous genotype conferred greater risk (OR = 1.9), and a similar association was observed with the IL1B rs3136558 CC genotype (OR = 1.89). Additionally, severely ill patients were compared with moderately ill patients. The TNF-238 GA genotype was associated with an increased risk of disease severity (OR = 16.06, p = 0.007). Compared with ILIs, patients with severe pA/H1N1 infections exhibited increased serum IL-5 (p <0.001) and IL-6 (p  =  0.007) levels. Conclusions The TNF gene was associated with disease severity, whereas IL1B and IL6 SNPs were

  2. TNF, IL6, and IL1B Polymorphisms Are Associated with Severe Influenza A (H1N1 Virus Infection in the Mexican Population.

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    Román Alejandro García-Ramírez

    Full Text Available Hypercytokinemia is the main immunopathological mechanism contributing to a more severe clinical course in influenza A (H1N1 virus infections. Most patients infected with the influenza A (H1N1 pdm09 virus had increased systemic levels of pro-inflammatory cytokines; including interleukin IL-6, IL-8, and tumor necrosis factor-alpha (TNF-α. We propose that single-nucleotide polymorphisms (SNPs in the promoter regions of pro-inflammatory genes are associated with the severity of influenza A (H1N1 pdm09 virus infection.145 patients with influenza A (H1N1 (pA/H1N1, 133 patients with influenza-like illness (ILI, and 360 asymptomatic healthy contacts (AHCs were included. Eleven SNPs were genotyped in six genes (TNF, LT, IL1B, IL6, CCL1, and IL8 using real-time PCR; the ancestral genotype was used for comparison. Genotypes were correlated with 27 clinical severity variables. Ten cytokines (GM-CSF, TNF-α, IL-2, IL-1β, IL-6, IL-8, IFN-γ, IL-10, IL-5, and IL-4 were measured on a Luminex 100.The IL6 rs1818879 (GA heterozygous genotype was associated with severe influenza A (H1N1 virus infection (odds ratio [OR] = 5.94, 95% confidence interval [CI] 3.05-11.56, and two IL1B SNPs, rs16944 AG and rs3136558 TC, were associated with a decreased risk of infection (OR = 0.52 and OR = 0.51, respectively. Genetic susceptibility was determined (pA/H1N1 vs. AHC: the LTA rs909253 TC heterozygous genotype conferred greater risk (OR = 1.9, and a similar association was observed with the IL1B rs3136558 CC genotype (OR = 1.89. Additionally, severely ill patients were compared with moderately ill patients. The TNF-238 GA genotype was associated with an increased risk of disease severity (OR = 16.06, p = 0.007. Compared with ILIs, patients with severe pA/H1N1 infections exhibited increased serum IL-5 (p <0.001 and IL-6 (p  =  0.007 levels.The TNF gene was associated with disease severity, whereas IL1B and IL6 SNPs were associated with influenza A (H1N1 virus

  3. Highly pathogenic avian influenza virus subtype H5N1 in Africa: a comprehensive phylogenetic analysis and molecular characterization of isolates.

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    Giovanni Cattoli

    Full Text Available Highly pathogenic avian influenza virus A/H5N1 was first officially reported in Africa in early 2006. Since the first outbreak in Nigeria, this virus spread rapidly to other African countries. From its emergence to early 2008, 11 African countries experienced A/H5N1 outbreaks in poultry and human cases were also reported in three of these countries. At present, little is known of the epidemiology and molecular evolution of A/H5N1 viruses in Africa. We have generated 494 full gene sequences from 67 African isolates and applied molecular analysis tools to a total of 1,152 A/H5N1 sequences obtained from viruses isolated in Africa, Europe and the Middle East between 2006 and early 2008. Detailed phylogenetic analyses of the 8 gene viral segments confirmed that 3 distinct sublineages were introduced, which have persisted and spread across the continent over this 2-year period. Additionally, our molecular epidemiological studies highlighted the association between genetic clustering and area of origin in a majority of cases. Molecular signatures unique to strains isolated in selected areas also gave us a clearer picture of the spread of A/H5N1 viruses across the continent. Mutations described as typical of human influenza viruses in the genes coding for internal proteins or associated with host adaptation and increased resistance to antiviral drugs have also been detected in the genes coding for transmembrane proteins. These findings raise concern for the possible human health risk presented by viruses with these genetic properties and highlight the need for increased efforts to monitor the evolution of A/H5N1 viruses across the African continent. They further stress how imperative it is to implement sustainable control strategies to improve animal and public health at a global level.

  4. Comparative epidemiology of human infections with avian influenza A H7N9 and H5N1 viruses in China: a population-based study of laboratory-confirmed cases.

    Science.gov (United States)

    Cowling, Benjamin J; Jin, Lianmei; Lau, Eric H Y; Liao, Qiaohong; Wu, Peng; Jiang, Hui; Tsang, Tim K; Zheng, Jiandong; Fang, Vicky J; Chang, Zhaorui; Ni, Michael Y; Zhang, Qian; Ip, Dennis K M; Yu, Jianxing; Li, Yu; Wang, Liping; Tu, Wenxiao; Meng, Ling; Wu, Joseph T; Luo, Huiming; Li, Qun; Shu, Yuelong; Li, Zhongjie; Feng, Zijian; Yang, Weizhong; Wang, Yu; Leung, Gabriel M; Yu, Hongjie

    2013-07-13

    The novel influenza A H7N9 virus emerged recently in mainland China, whereas the influenza A H5N1 virus has infected people in China since 2003. Both infections are thought to be mainly zoonotic. We aimed to compare the epidemiological characteristics of the complete series of laboratory-confirmed cases of both viruses in mainland China so far. An integrated database was constructed with information about demographic, epidemiological, and clinical variables of laboratory-confirmed cases of H7N9 (130 patients) and H5N1 (43 patients) that were reported to the Chinese Centre for Disease Control and Prevention until May 24, 2013. We described disease occurrence by age, sex, and geography, and estimated key epidemiological variables. We used survival analysis techniques to estimate the following distributions: infection to onset, onset to admission, onset to laboratory confirmation, admission to death, and admission to discharge. The median age of the 130 individuals with confirmed infection with H7N9 was 62 years and of the 43 with H5N1 was 26 years. In urban areas, 74% of cases of both viruses were in men, whereas in rural areas the proportions of the viruses in men were 62% for H7N9 and 33% for H5N1. 75% of patients infected with H7N9 and 71% of those with H5N1 reported recent exposure to poultry. The mean incubation period of H7N9 was 3·1 days and of H5N1 was 3·3 days. On average, 21 contacts were traced for each case of H7N9 in urban areas and 18 in rural areas, compared with 90 and 63 for H5N1. The fatality risk on admission to hospital was 36% (95% CI 26-45) for H7N9 and 70% (56-83%) for H5N1. The sex ratios in urban compared with rural cases are consistent with exposure to poultry driving the risk of infection--a higher risk in men was only recorded in urban areas but not in rural areas, and the increased risk for men was of a similar magnitude for H7N9 and H5N1. However, the difference in susceptibility to serious illness with the two different viruses

  5. Multiplex RT-PCR assay for differentiating European swine influenza virus subtypes H1N1, H1N2 and H3N2.

    Science.gov (United States)

    Chiapponi, Chiara; Moreno, Ana; Barbieri, Ilaria; Merenda, Marianna; Foni, Emanuela

    2012-09-01

    In Europe, three major swine influenza viral (SIV) subtypes (H1N1, H1N2 and H3N2) have been isolated in pigs. Developing a test that is able to detect and identify the subtype of the circulating strain rapidly during an outbreak of respiratory disease in the pig population is of essential importance. This study describes two multiplex RT-PCRs which distinguish the haemagglutinin (HA) gene and the neuraminidase (NA) gene of the three major subtypes of SIV circulating in Europe. The HA PCR was able to identify the lineage (avian or human) of the HA of H1 subtypes. The analytical sensitivity of the test, considered to be unique, was assessed using three reference viruses. The detection limit corresponded to 1×10(-1) TCID(50)/200μl for avian-like H1N1, 1×10(0) TCID(50)/200μl for human-like H1N2 and 1×10(1) TCID(50)/200μl for H3N2 SIV. The multiplex RT-PCR was first carried out on a collection of 70 isolated viruses showing 100% specificity and then on clinical samples, from which viruses had previously been isolated, resulting in an 89% positive specificity of the viral subtype. Finally, the test was able to identify the viral subtype correctly in 56% of influenza A positive samples, from which SIV had not been isolated previously. It was also possible to identify mixed viral infections and the circulation of a reassortant strain before performing genomic studies. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Neuraminidase and hemagglutinin matching patterns of a highly pathogenic avian and two pandemic H1N1 influenza A viruses.

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    Yonghui Zhang

    Full Text Available BACKGROUND: Influenza A virus displays strong reassortment characteristics, which enable it to achieve adaptation in human infection. Surveying the reassortment and virulence of novel viruses is important in the prevention and control of an influenza pandemic. Meanwhile, studying the mechanism of reassortment may accelerate the development of anti-influenza strategies. METHODOLOGY/PRINCIPAL FINDINGS: The hemagglutinin (HA and neuraminidase (NA matching patterns of two pandemic H1N1 viruses (the 1918 and current 2009 strains and a highly pathogenic avian influenza A virus (H5N1 were studied using a pseudotyped particle (pp system. Our data showed that four of the six chimeric HA/NA combinations could produce infectious pps, and that some of the chimeric pps had greater infectivity than did their ancestors, raising the possibility of reassortment among these viruses. The NA of H5N1 (A/Anhui/1/2005 could hardly reassort with the HAs of the two H1N1 viruses. Many biological characteristics of HA and NA, including infectivity, hemagglutinating ability, and NA activity, are dependent on their matching pattern. CONCLUSIONS/SIGNIFICANCE: Our data suggest the existence of an interaction between HA and NA, and the HA NA matching pattern is critical for valid viral reassortment.

  7. The 2009 A (H1N1) influenza virus pandemic: A review.

    Science.gov (United States)

    Girard, Marc P; Tam, John S; Assossou, Olga M; Kieny, Marie Paule

    2010-07-12

    In March and early April 2009 a new swine-origin influenza virus (S-OIV), A (H1N1), emerged in Mexico and the USA. The virus quickly spread worldwide through human-to-human transmission. In view of the number of countries and communities which were reporting human cases, the World Health Organization raised the influenza pandemic alert to the highest level (level 6) on June 11, 2009. The propensity of the virus to primarily affect children, young adults and pregnant women, especially those with an underlying lung or cardiac disease condition, and the substantial increase in rate of hospitalizations, prompted the efforts of the pharmaceutical industry, including new manufacturers from China, Thailand, India and South America, to develop pandemic H1N1 influenza vaccines. All currently registered vaccines were tested for safety and immunogenicity in clinical trials on human volunteers. All were found to be safe and to elicit potentially protective antibody responses after the administration of a single dose of vaccine, including split inactivated vaccines with or without adjuvant, whole-virion vaccines and live-attenuated vaccines. The need for an increased surveillance of influenza virus circulation in swine is outlined. Copyright 2010. Published by Elsevier Ltd.

  8. Characterization of a non-pathogenic H5N1 influenza virus isolated from a migratory duck flying from Siberia in Hokkaido, Japan, in October 2009

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    Okamatsu Masatoshi

    2011-02-01

    Full Text Available Abstract Background Infection with H5N1 highly pathogenic avian influenza viruses (HPAIVs of domestic poultry and wild birds has spread to more than 60 countries in Eurasia and Africa. It is concerned that HPAIVs may be perpetuated in the lakes in Siberia where migratory water birds nest in summer. To monitor whether HPAIVs circulate in migratory water birds, intensive surveillance of avian influenza has been performed in Mongolia and Japan in autumn each year. Until 2008, there had not been any H5N1 viruses isolated from migratory water birds that flew from their nesting lakes in Siberia. In autumn 2009, A/mallard/Hokkaido/24/09 (H5N1 (Mal/Hok/24/09 was isolated from a fecal sample of a mallard (Anas platyrhynchos that flew from Siberia to Hokkaido, Japan. The isolate was assessed for pathogenicity in chickens, domestic ducks, and quails and analyzed antigenically and phylogenetically. Results No clinical signs were observed in chickens inoculated intravenously with Mal/Hok/24/09 (H5N1. There was no viral replication in chickens inoculated intranasally with the isolate. None of the domestic ducks and quails inoculated intranasally with the isolate showed any clinical signs. There were no multiple basic amino acid residues at the cleavage site of the hemagglutinin (HA of the isolate. Each gene of Mal/Hok/24/09 (H5N1 is phylogenetically closely related to that of influenza viruses isolated from migratory water birds that flew from their nesting lakes in autumn. Additionally, the antigenicity of the HA of the isolate was similar to that of the viruses isolated from migratory water birds in Hokkaido that flew from their northern territory in autumn and different from those of HPAIVs isolated from birds found dead in China, Mongolia, and Japan on the way back to their northern territory in spring. Conclusion Mal/Hok/24/09 (H5N1 is a non-pathogenic avian influenza virus for chickens, domestic ducks, and quails, and is antigenically and genetically

  9. The Neurological Manifestations of H1N1 Influenza Infection; Diagnostic Challenges and Recommendations

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    Ali Akbar Asadi-Pooya

    2011-03-01

    Full Text Available Background: World Health Organization declared pandemic phase of human infection with novel influenza A (H1N1 in April 2009. There are very few reports about the neurological complications of H1N1 virus infection in the literature. Occasionally, these complications are severe and even fatal in some individuals. The aims of this study were to report neurological complaints and/or complications associated with H1N1 virus infection. Methods: The medical files of all patients with H1N1 influenza infection admitted to a specified hospital in the city of Shiraz, Iran from October through November 2009 were reviewed. More information about the patients were obtained by phone calls to the patients or their care givers. All patients had confirmed H1N1 virus infection with real-time PCR assay. Results: Fifty-five patients with H1N1 infection were studied. Twenty-three patients had neurological signs and/or symptoms. Mild neurological complaints may be reported in up to 42% of patients infected by H1N1 virus. Severe neurological complications occurred in 9% of the patients. The most common neurological manifestations were headache, numbness and paresthesia, drowsiness and coma. One patient had a Guillain-Barre syndrome-like illness, and died in a few days. Another patient had focal status epilepticus and encephalopathy. Conclusions: The H1N1 infection seems to have been quite mild with a self-limited course in much of the world, yet there appears to be a subset, which is severely affected. We recommend performing diagnostic tests for H1N1influenza virus in all patients with respiratory illness and neurological signs/symptoms. We also recommend initiating treatment with appropriate antiviral drugs as soon as possible in those with any significant neurological presentation accompanied with respiratory illness and flu-like symptoms

  10. Avian influenza A H5N1 infections in Bali Province, Indonesia: a behavioral, virological and seroepidemiological study.

    Science.gov (United States)

    Santhia, Ketut; Ramy, Ayu; Jayaningsih, Putri; Samaan, Gina; Putra, Anak Agung Gde; Dibia, Nyoman; Sulaimin, Cynthia; Joni, Gusti; Leung, Connie Y H; Sriyal, Joseph; Peiris, Malik; Wandra, Toni; Kandun, Nyoman

    2009-05-01

    Bali Province was affected by avian influenza H5N1 outbreaks in birds in October 2003. Despite ongoing circulation of the virus, no human infection had been identified by December 2005. To assess behavioral patterns associated with poultry rearing in Bali, and to identify potential risk factors for H5N1 infection in humans and in household chickens, ducks and pigs. A behavioral, virological and seroepidemiologic survey in 38 villages and three live bird markets was completed in December 2005. A multi-stage cluster design was used to select 291 households with 841 participants from all nine districts in Bali. Specimens were collected from participants as well as a maximum of three pigs, chickens and ducks from each household. Eighty-seven market vendors participated, where specimens were collected from participants as well as chickens and ducks. Twenty out of the 38 villages sampled had H5N1 outbreaks. Despite exposure to H5N1 outbreaks, none of the participants from villages or markets were seropositive for H5N1. None of the pigs tested were positive for H5N1. Virus isolation rate in ducks and chicken in markets was higher than in households. Transport of poultry in or out of villages was a risk factor for outbreaks in household chickens and ducks. The study highlighted that the market chain and associated behaviors may play a role in maintaining the virus in household flocks. The study adds evidence that transmission of H5N1 to humans remains a rare event despite high level handling of both healthy and sick birds.

  11. Adoption of Preventive Measures and Attitudes toward the H1N1 Influenza Pandemic in Schools

    Science.gov (United States)

    Pérez, Anna; Rodríguez, Tània; López, Maria José; Continente, Xavier; Nebot, Manel

    2016-01-01

    Background: This study describes the perceived impact of H1N1 influenza and the adoption of the recommended measures to address the pandemic in schools. Methods: A cross-sectional self-reported survey was conducted in 433 schools in Barcelona addressed to the school principal or the H1N1 influenza designated person. A descriptive analysis was…

  12. Case of seasonal reassortant a(H1N2) influenza virus infection, the Netherlands, March 2018

    NARCIS (Netherlands)

    Meijer, A. (Adam); C. Swaan (Corien); Voerknecht, M. (Martin); E. Jusic (Edin); van den Brink, S. (Sharon); Wijsman, L.A. (Lisa A.); A.C.G. Voordouw (Bettie); G.A. Donker (Gé); Sleven, J. (Jacqueline); Dorigo-Zetsma, W.W. (Wendelien W.); S. Svraka-Latifovic (Sanela); M. van Boven (Michiel); Haverkate, M.R. (Manon R.); A. Timen (Aura); J.T. van Dissel (Jaap); M.P.G. Koopmans D.V.M. (Marion); T.M. Bestebroer (Theo); R.A.M. Fouchier (Ron)

    2018-01-01

    textabstractA seasonal reassortant A(H1N2) influenza virus harbouring genome segments from seasonal influenza viruses A(H1N1)pdm09 (HA and NS) and A(H3N2) (PB2, PB1, PA, NP, NA and M) was identified in March 2018 in a 19-months-old patient with influenza-like illness (ILI) who presented to a general

  13. Evolution and adaptation of the pandemic A/H1N1 2009 influenza virus

    Directory of Open Access Journals (Sweden)

    Ducatez MF

    2011-07-01

    Full Text Available Mariette F Ducatez, Thomas P Fabrizio, Richard J WebbyDepartment of Infectious Diseases, St Jude Children's Research Hospital, Memphis, TN, USAAbstract: The emergence of the 2009 H1N1 pandemic influenza virus [A(H1N1pdm09] has provided the public health community with many challenges, but also the scientific community with an opportunity to monitor closely its evolution through the processes of drift and shift. To date, and despite having circulated in humans for nearly two years, little antigenic variation has been observed in the A(H1N1pdm09 viruses. However, as the A(H1N1pdm09 virus continues to circulate and the immunologic pressure within the human population increases, future antigenic change is almost a certainty. Several coinfections of A(H1N1pdm09 and seasonal A(H1N1 or A(H3N2 viruses have been observed, but no reassortant viruses have been described in humans, suggesting a lack of fitness of reassortant viruses or a lack of opportunities for interaction of different viral lineages. In contrast, multiple reassortment events have been detected in swine populations between A(H1N1 pdm09 and other endemic swine viruses. Somewhat surprisingly, many of the well characterized influenza virus virulence markers appear to have limited impact on the phenotype of the A(H1N1pdm09 viruses when they have been introduced into mutant viruses in laboratory settings. As such, it is unclear what the evolutionary path of the pandemic virus will be, but the monitoring of any changes in the circulating viruses will remain a global public and animal health priority.Keywords: influenza, pandemic, evolution, adaptation

  14. Avian influenza viruses that cause highly virulent infections in humans exhibit distinct replicative properties in contrast to human H1N1 viruses

    Science.gov (United States)

    Simon, Philippe F.; de La Vega, Marc-Antoine; Paradis, Éric; Mendoza, Emelissa; Coombs, Kevin M.; Kobasa, Darwyn; Beauchemin, Catherine A. A.

    2016-04-01

    Avian influenza viruses present an emerging epidemiological concern as some strains of H5N1 avian influenza can cause severe infections in humans with lethality rates of up to 60%. These have been in circulation since 1997 and recently a novel H7N9-subtyped virus has been causing epizootics in China with lethality rates around 20%. To better understand the replication kinetics of these viruses, we combined several extensive viral kinetics experiments with mathematical modelling of in vitro infections in human A549 cells. We extracted fundamental replication parameters revealing that, while both the H5N1 and H7N9 viruses replicate faster and to higher titers than two low-pathogenicity H1N1 strains, they accomplish this via different mechanisms. While the H7N9 virions exhibit a faster rate of infection, the H5N1 virions are produced at a higher rate. Of the two H1N1 strains studied, the 2009 pandemic H1N1 strain exhibits the longest eclipse phase, possibly indicative of a less effective neuraminidase activity, but causes infection more rapidly than the seasonal strain. This explains, in part, the pandemic strain’s generally slower growth kinetics and permissiveness to accept mutations causing neuraminidase inhibitor resistance without significant loss in fitness. Our results highlight differential growth properties of H1N1, H5N1 and H7N9 influenza viruses.

  15. Isolation and Characterization of Avian Influenza Viruses, Including Highly Pathogenic H5N1, from Poultry in Live Bird Markets in Hanoi, Vietnam, in 2001

    Science.gov (United States)

    Nguyen, Doan C.; Uyeki, Timothy M.; Jadhao, Samadhan; Maines, Taronna; Shaw, Michael; Matsuoka, Yumiko; Smith, Catherine; Rowe, Thomas; Lu, Xiuhua; Hall, Henrietta; Xu, Xiyan; Balish, Amanda; Klimov, Alexander; Tumpey, Terrence M.; Swayne, David E.; Huynh, Lien P. T.; Nghiem, Ha K.; Nguyen, Hanh H. T.; Hoang, Long T.; Cox, Nancy J.; Katz, Jacqueline M.

    2005-01-01

    Since 1997, outbreaks of highly pathogenic (HP) H5N1 and circulation of H9N2 viruses among domestic poultry in Asia have posed a threat to public health. To better understand the extent of transmission of avian influenza viruses (AIV) to humans in Asia, we conducted a cross-sectional virologic study in live bird markets (LBM) in Hanoi, Vietnam, in October 2001. Specimens from 189 birds and 18 environmental samples were collected at 10 LBM. Four influenza A viruses of the H4N6 (n = 1), H5N2 (n = 1), and H9N3 (n = 2) subtypes were isolated from healthy ducks for an isolation frequency of over 30% from this species. Two H5N1 viruses were isolated from healthy geese. The hemagglutinin (HA) genes of these H5N1 viruses possessed multiple basic amino acid motifs at the cleavage site, were HP for experimentally infected chickens, and were thus characterized as HP AIV. These HA genes shared high amino acid identities with genes of other H5N1 viruses isolated in Asia during this period, but they were genetically distinct from those of H5N1 viruses isolated from poultry and humans in Vietnam during the early 2004 outbreaks. These viruses were not highly virulent for experimentally infected ducks, mice, or ferrets. These results establish that HP H5N1 viruses with properties similar to viruses isolated in Hong Kong and mainland China circulated in Vietnam as early as 2001, suggest a common source for H5N1 viruses circulating in these Asian countries, and provide a framework to better understand the recent widespread emergence of HP H5N1 viruses in Asia. PMID:15767421

  16. Diversity of the murine antibody response targeting influenza A(H1N1pdm09) hemagglutinin.

    Science.gov (United States)

    Wilson, Jason R; Tzeng, Wen-Pin; Spesock, April; Music, Nedzad; Guo, Zhu; Barrington, Robert; Stevens, James; Donis, Ruben O; Katz, Jacqueline M; York, Ian A

    2014-06-01

    We infected mice with the 2009 influenza A pandemic virus (H1N1pdm09), boosted with an inactivated vaccine, and cloned immunoglobulins (Igs) from HA-specific B cells. Based on the redundancy in germline gene utilization, we inferred that between 72-130 unique IgH VDJ and 35 different IgL VJ combinations comprised the anti-HA recall response. The IgH VH1 and IgL VK14 variable gene families were employed most frequently. A representative panel of antibodies were cloned and expressed to confirm reactivity with H1N1pdm09 HA. The majority of the recombinant antibodies were of high avidity and capable of inhibiting H1N1pdm09 hemagglutination. Three of these antibodies were subtype-specific cross-reactive, binding to the HA of A/South Carolina/1/1918(H1N1), and one further reacted with A/swine/Iowa/15/1930(H1N1). These results help to define the genetic diversity of the influenza anti-HA antibody repertoire profile induced following infection and vaccination, which may facilitate the development of influenza vaccines that are more protective and broadly neutralizing. Protection against influenza viruses is mediated mainly by antibodies, and in most cases this antibody response is narrow, only providing protection against closely related viruses. In spite of this limited range of protection, recent findings indicate that individuals immune to one influenza virus may contain antibodies (generally a minority of the overall response) that are more broadly reactive. These findings have raised the possibility that influenza vaccines could induce a more broadly protective response, reducing the need for frequent vaccine strain changes. However, interpretation of these observations is hampered by the lack of quantitative characterization of the antibody repertoire. In this study, we used single-cell cloning of influenza HA-specific B cells to assess the diversity and nature of the antibody response to influenza hemagglutinin in mice. Our findings help to put bounds on the

  17. Seroprevalence of avian influenza A (H5N1 virus among poultry workers in Jiangsu Province, China: an observational study

    Directory of Open Access Journals (Sweden)

    Huo Xiang

    2012-04-01

    Full Text Available Abstract Background Since 2003 to 06 Jan 2012, the number of laboratory confirmed human cases of infection with avian influenza in China was 41 and 27 were fatal. However, the official estimate of the H5N1 case-fatality rate has been described by some as an over estimation since there may be numerous undetected asymptomatic/mild cases of H5N1 infection. This study was conducted to better understand the real infection rate and evaluate the potential risk factors for the zoonotic spread of H5N1 viruses to humans. Methods A seroepidemiological survey was conducted in poultry workers, a group expected to have the highest level of exposure to H5N1-infected birds, from 3 counties with habitat lakes of wildfowl in Jiangsu province, China. Serum specimens were collected from 306 participants for H5N1 serological test. All participants were interviewed to collect information about poultry exposures. Results The overall seropositive rate was 2.61% for H5N1 antibodies. The poultry number was found associated with a 2.39-fold significantly increased subclinical infection risk after adjusted with age and gender. Conclusions Avian-to -human transmission of avian H5N1 virus remained low. Workers associated with raising larger poultry flocks have a higher risk on seroconversion.

  18. Infectivity, transmission and pathogenicity of H5 highly pathogenic avian influenza clade 2.3.4.4 (H5N8 and H5N2) United States index viruses in Pekin ducks and Chinese geese

    Science.gov (United States)

    In late 2014, a H5N8 highly pathogenic avian influenza (HPAI) virus, clade 2.3.4.4, spread by migratory birds into North America mixing with low pathogenicity AI viruses to produce a H5N2 HPAI virus. The H5N8 and H5N2 HPAI viruses were detected initially in wild waterfowl and backyard birds, and lat...

  19. Acquisition of human-type receptor binding specificity by new H5N1 influenza virus sublineages during their emergence in birds in Egypt.

    Directory of Open Access Journals (Sweden)

    Yohei Watanabe

    2011-05-01

    Full Text Available Highly pathogenic avian influenza A virus subtype H5N1 is currently widespread in Asia, Europe, and Africa, with 60% mortality in humans. In particular, since 2009 Egypt has unexpectedly had the highest number of human cases of H5N1 virus infection, with more than 50% of the cases worldwide, but the basis for this high incidence has not been elucidated. A change in receptor binding affinity of the viral hemagglutinin (HA from α2,3- to α2,6-linked sialic acid (SA is thought to be necessary for H5N1 virus to become pandemic. In this study, we conducted a phylogenetic analysis of H5N1 viruses isolated between 2006 and 2009 in Egypt. The phylogenetic results showed that recent human isolates clustered disproportionally into several new H5 sublineages suggesting that their HAs have changed their receptor specificity. Using reverse genetics, we found that these H5 sublineages have acquired an enhanced binding affinity for α2,6 SA in combination with residual affinity for α2,3 SA, and identified the amino acid mutations that produced this new receptor specificity. Recombinant H5N1 viruses with a single mutation at HA residue 192 or a double mutation at HA residues 129 and 151 had increased attachment to and infectivity in the human lower respiratory tract but not in the larynx. These findings correlated with enhanced virulence of the mutant viruses in mice. Interestingly, these H5 viruses, with increased affinity to α2,6 SA, emerged during viral diversification in bird populations and subsequently spread to humans. Our findings suggested that emergence of new H5 sublineages with α2,6 SA specificity caused a subsequent increase in human H5N1 influenza virus infections in Egypt, and provided data for understanding the virus's pandemic potential.

  20. In silico approach towards H5N1 virus protein and transcriptomics ...

    African Journals Online (AJOL)

    H5N1 influenza A virus is a serious threat to human population. With a considerable mortality rate, strategies for coping with the infection are being developed. Our research group and some others investigated the potential therapeutic and preventive measures for tackling H5N1 infections. Protein based and transcriptomics ...

  1. School illness absenteeism during 2009 influenza A (H1N1) pandemic--South Dakota, 2009-2010.

    Science.gov (United States)

    Kightlinger, Lon; Horan, Vickie

    2013-05-01

    Schools are important amplification settings of influenza virus transmission. We demonstrated correlation of school absenteeism (due to any illness) with other influenza A (H1N1) activity surveillance data during the 2009 pandemic. We collected nonspecific illness student absenteeism data from August 17, 2009 through April 3, 2010 from 187 voluntarily participating South Dakota schools using weekly online surveys. Relative risks (RR) were calculated as the ratio of the probability of absenteeism during elevated weeks versus the probability of absenteeism during the baseline weeks (RR = 1.89). We used Pearson correlation to associate absenteeism with laboratory-confirmed influenza cases, influenza cases diagnosed by rapid tests, influenza-associated hospitalizations and deaths reported in South Dakota during the 2009 H1N1 pandemic period. School-absenteeism data correlated strongly with data from these other influenza surveillance sources.

  2. Prevalence and distribution of avian influenza a(H5N1) virus clade variants in live bird markets of Vietnam, 2011-2013.

    Science.gov (United States)

    Nguyen, Diep T; Bryant, Juliet E; Davis, C Todd; Nguyen, Long V; Pham, Long T; Loth, Leo; Inui, Ken; Nguyen, Tung; Jang, Yunho; To, Thanh L; Nguyen, Tho D; Hoang, Diep T; Do, Hoa T; Nguyen, Trang T; Newman, Scott; Jennifer Siembieda; Pham, Dong V

    2014-12-01

    Active surveillance for avian influenza (Al) viruses in poultry sold at live bird markets (LBMs) was conducted in 44 of 63 provinces throughout Vietnam over two periods from September 2011 to February 2012 and October 2012 to June 2013. The study objectives were to assess the prevalence of avian influenza type A, H5, and H5N1 subtype viruses and characterize the geographical and temporal distribution of H5N1 virus genetic variants across the country. Monthly sampling was conducted in 394 LBMs located in 372 communes. A total of 9790 oropharyngeal swabs from poultry were screened for influenza A virus by real-time reverse-transcriptase PCR Virus isolation was attempted on all positive samples in embryonated chicken eggs, and the HA1 region of each H5 virus isolate was sequenced. Market prevalence of H5 subtype virus was 32.2% (127/394) over the cumulative 15 mo of surveillance. Phylogenetic analyses indicated that clade 1.1 viruses persisted in the south, whereas three genetically distinct subgroups of dade 2.3.2.1 were found simultaneously in northern, central, and southern Vietnam. Clade 2.3.2.1c viruses first appeared in July 2012 and spread rapidly to the center and south of Vietnam in late 2012, where they were predominant among clade 2.3.2.1 viruses and were detected in both active LBM surveillance and poultry outbreaks. Given the overlapping geographic distribution of dade variants and the antigenic divergence previously described for these dades, current AI poultry vaccines used in Vietnam may require bivalent formulations containing representatives of both dade 1.1 and dade 2.3.2.1 viruses.

  3. Comparative study of the hemagglutinin and neuraminidase genes of influenza A virus H3N2, H9N2, and H5N1 subtypes using bioinformatics techniques.

    Science.gov (United States)

    Ahn, Insung; Son, Hyeon S

    2007-07-01

    To investigate the genomic patterns of influenza A virus subtypes, such as H3N2, H9N2, and H5N1, we collected 1842 sequences of the hemagglutinin and neuraminidase genes from the NCBI database and parsed them into 7 categories: accession number, host species, sampling year, country, subtype, gene name, and sequence. The sequences that were isolated from the human, avian, and swine populations were extracted and stored in a MySQL database for intensive analysis. The GC content and relative synonymous codon usage (RSCU) values were calculated using JAVA codes. As a result, correspondence analysis of the RSCU values yielded the unique codon usage pattern (CUP) of each subtype and revealed no extreme differences among the human, avian, and swine isolates. H5N1 subtype viruses exhibited little variation in CUPs compared with other subtypes, suggesting that the H5N1 CUP has not yet undergone significant changes within each host species. Moreover, some observations may be relevant to CUP variation that has occurred over time among the H3N2 subtype viruses isolated from humans. All the sequences were divided into 3 groups over time, and each group seemed to have preferred synonymous codon patterns for each amino acid, especially for arginine, glycine, leucine, and valine. The bioinformatics technique we introduce in this study may be useful in predicting the evolutionary patterns of pandemic viruses.

  4. A novel monoclonal antibody effective against lethal challenge with swine-lineage and 2009 pandemic H1N1 influenza viruses in mice

    Science.gov (United States)

    The HA protein of the 2009 pandemic H1N1viruses (14 H1N1pdm) is antigenically closely related to the HA of classical North American swine H1N1 influenza viruses (cH1N1). Since 1998, through reassortment and incorporation of HA genes from human H3N2 and H1N1 influenza viruses, swine influenza strains...

  5. H1N1 Influenza A hos mennesker og svin

    DEFF Research Database (Denmark)

    Larsen, Lars Erik

    2009-01-01

    Den nye pandemiske influenza A stamme H1N1 er hovedsagelig et nyt virus, som spredes mellem mennesker, men virusset er formodentlig opstået ved blanding af to svineinfluenza-virus og har derfor bibeholdt evnen til at kunne smitte fra mennesker til svin og fra svin til svin. Det er derfor vigtigt...

  6. High mortality from respiratory failure secondary to swine-origin influenza A (H1N1) in South Africa.

    Science.gov (United States)

    Koegelenberg, C F N; Irusen, E M; Cooper, R; Diacon, A H; Taljaard, J J; Mowlana, A; von Groote-Bidlingmaier, F; Bolliger, C T

    2010-05-01

    The novel influenza A (H1N1) pandemic affected South Africa late during the 2009 Southern hemisphere winter and placed an extra burden on a health care system already dealing with a high prevalence of chronic lung diseases and human immunodeficiency virus (HIV) infection. The aim of this study was to describe the epidemiological characteristics, clinical features, management and outcomes of patients with confirmed influenza A (H1N1) infection complicated by respiratory failure. We included all adult patients with confirmed influenza A (H1N1) infection that were referred to the medical intensive care unit of a large academic hospital in Cape Town for ventilatory support in this prospective observational study. A total of 19 patients (39.5 +/- 14.8 years) needed ventilatory support over a 6-week period. Of these, 15 were female and 16 had identifiable risk factors for severe disease, including pregnancy (n = 6), type 2 diabetes mellitus (n = 6), obesity (n = 4), HIV infection (n = 3), immunosuppressive therapy (n = 3) and active pulmonary tuberculosis (n = 2). The most frequent complications were acute renal failure (n = 13), acute respiratory distress syndrome (n = 12) and ventilator associated pneumonia (n = 10). Thirteen patients died (mortality: 68.4%). Fatal cases were significantly associated with an APACHE II score >or=20 (P = 0.034), but not with a P(a)O(2)/F(I)O(2) or=12 (P = 0.134). The majority of patients with respiratory failure secondary to influenza A (H1N1) infection were young females and had an underlying risk factor for severe disease. The condition had a high mortality, particularly amongst patients with an APACHE II score >or=20.

  7. Identification of swine H1N2/pandemic H1N1 reassortant influenza virus in pigs, United States.

    Science.gov (United States)

    Ali, Ahmed; Khatri, Mahesh; Wang, Leyi; Saif, Yehia M; Lee, Chang-Won

    2012-07-06

    In October and November 2010, novel H1N2 reassortant influenza viruses were identified from pigs showing mild respiratory signs that included cough and depression. Sequence and phylogenetic analysis showed that the novel H1N2 reassortants possesses HA and NA genes derived from recent H1N2 swine isolates similar to those isolated from Midwest. Compared to the majority of reported reassortants, both viruses preserved human-like host restrictive and putative antigenic sites in their HA and NA genes. The four internal genes, PB2, PB1, PA, and NS were similar to the contemporary swine triple reassortant viruses' internal genes (TRIG). Interestingly, NP and M genes of the novel reassortants were derived from the 2009 pandemic H1N1. The NP and M proteins of the two isolates demonstrated one (E16G) and four (G34A, D53E, I109T, and V313I) amino acid changes in the M2 and NP proteins, respectively. Similar amino acid changes were also noticed upon incorporation of the 2009 pandemic H1N1 NP in other reassortant viruses reported in the U.S. Thus the role of those amino acids in relation to host adaptation need to be further investigated. The reassortments of pandemic H1N1 with swine influenza viruses and the potential of interspecies transmission of these reassortants from swine to other species including human indicate the importance of systematic surveillance of swine population to determine the origin, the prevalence of similar reassortants in the U.S. and their impact on both swine production and public health. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Household transmission of influenza A(H1N1pdm09 in the pandemic and post-pandemic seasons.

    Directory of Open Access Journals (Sweden)

    Itziar Casado

    Full Text Available The transmission of influenza viruses occurs person to person and is facilitated by contacts within enclosed environments such as households. The aim of this study was to evaluate secondary attack rates and factors associated with household transmission of laboratory-confirmed influenza A(H1N1pdm09 in the pandemic and post-pandemic seasons.During the 2009-2010 and 2010-2011 influenza seasons, 76 sentinel physicians in Navarra, Spain, took nasopharyngeal and pharyngeal swabs from patients diagnosed with influenza-like illness. A trained nurse telephoned households of those patients who were laboratory-confirmed for influenza A(H1N1pdm09 to ask about the symptoms, risk factors and vaccination status of each household member.In the 405 households with a patient laboratory-confirmed for influenza A(H1N1pdm09, 977 susceptible contacts were identified; 16% of them (95% CI 14-19% presented influenza-like illness and were considered as secondary cases. The secondary attack rate was 14% in 2009-2010 and 19% in the 2010-2011 season (p=0.049, an increase that mainly affected persons with major chronic conditions. In the multivariate logistic regression analysis, the risk of being a secondary case was higher in the 2010-2011 season than in the 2009-2010 season (adjusted odds ratio: 1.72; 95% CI 1.17-2.54, and in children under 5 years, with a decreasing risk in older contacts. Influenza vaccination was associated with lesser incidence of influenza-like illness near to statistical significance (adjusted odds ratio: 0.29; 95% CI 0.08-1.03.The secondary attack rate in households was higher in the second season than in the first pandemic season. Children had a greater risk of infection. Preventive measures should be maintained in the second pandemic season, especially in high-risk persons.

  9. 2009 Pandemic Influenza A Virus Subtype H1N1 in Morocco, 2009–2010: Epidemiology, Transmissibility, and Factors Associated With Fatal Cases

    Science.gov (United States)

    Barakat, Amal; Ihazmad, Hassan; El Falaki, Fatima; Tempia, Stefano; Cherkaoui, Imad; El Aouad, Rajae

    2012-01-01

    Background. Following the emergence of 2009 pandemic influenza A virus subtype H1N1 (A[H1N1]pdm09) in the United States and Mexico in April 2009, A(H1N1)pdm09 spread rapidly all over the world. There is a dearth of information about the epidemiology of A(H1N1)pdm09 in Africa, including Morocco. We describe the epidemiologic characteristics of the A(H1N1)pdm09 epidemic in Morocco during 2009–2010, including transmissibility and risk factors associated with fatal disease. Methods. We implemented influenza surveillance for patients presenting with influenza-like illness (ILI) at 136 private and public clinics for patients with severe acute respiratory illness (SARI) at 16 regional public hospitals from June 2009 through February 2010. Respiratory samples and structured questionnaires were collected from all enrolled patients, and samples were tested by real-time reverse-transcription polymerase chain reaction for influenza viruses. We estimated the risk factors associated with fatal disease as well as the basic reproduction number (R0) and the serial interval of the pandemic virus. Results. From June 2009 through February 2010, we obtained 3937 specimens, of which 1452 tested positive for influenza virus. Of these, 1398 (96%) were A(H1N1)pdm09. Forty percent of specimens from ILI cases (1056 of 2646) and 27% from SARI cases (342 of 1291) were positive for A(H1N1)pdm09. Sixty-four deaths occurred among laboratory-confirmed A(H1N1)pdm09 SARI cases. Among these cases, those who had hypertension (age-adjusted odd ratio [aOR], 28.2; 95% confidence interval [CI], 2.0–398.7), had neurological disorders (aOR, 7.5; 95% CI, 1.5–36.4), or were obese (aOR, 7.1; 95% CI, 1.6–31.1), as well as women of gestational age who were pregnant (aOR, 2.5; 95% CI, 1.15.6), were at increased risk of death. Across the country, elevated numbers of locally acquired infections were detected 4 months after the detection of the first laboratory-confirmed case and coincided with the

  10. Experimental infection of a North American raptor, American kestrel (Falco sparverius), with highly pathogenic avian influenza virus (H5N1)

    Science.gov (United States)

    Hall, Jeffrey S.; Ip, Hon S.; Franson, J.C.; Meteyer, C.; Nashold, Sean W.; Teslaa, Joshua L.; French, J.; Redig, P.; Brand, C.

    2009-01-01

    Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV) subtype H5N1. Should HPAIV (H5N1) reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1) infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1). All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1) is introduced into North America.

  11. Heterologous Prime-Boost Vaccination Using an AS03B-Adjuvanted Influenza A(H5N1) Vaccine in Infants and Children <3 Years of Age

    Science.gov (United States)

    Nolan, Terry; Izurieta, Patricia; Lee, Bee-Wah; Chan, Poh Chong; Marshall, Helen; Booy, Robert; Drame, Mamadou; Vaughn, David W.

    2014-01-01

    Background. Protecting young children from pandemic influenza should also reduce transmission to susceptible adults, including pregnant women. Methods. An open study assessed immunogenicity and reactogenicity of a heterologous booster dose of A/turkey/Turkey/1/2005(H5N1)-AS03B (AS03B is an Adjuvant System containing α-tocopherol and squalene in an oil-in-water emulsion [5.93 mg tocopherol]) in infants and children aged 6 to < 36 months that was given 6 months following 2-dose primary vaccination with A/Indonesia/05/2005(H5N1)-AS03B. Vaccines contained 1.9 µg of hemagglutinin antigen and AS03B. Hemagglutinin inhibition (HI) responses, microneutralization titers, and antineuraminidase antibody levels were assessed for 6 months following the booster vaccination. Results. For each age stratum (defined on the basis of the subject's age at first vaccination as 6 to < 12 months, 12 to < 24 months, and 24 to < 36 months) and overall (n = 113), European influenza vaccine licensure criteria were fulfilled for responses to A/turkey/Turkey/1/2005(H5N1) 10 days following the booster vaccination. Local pain and fever increased with consecutive doses. Anamnestic immune responses were demonstrated for HI, neutralizing, and antineuraminidase antibodies against vaccine-homologous/heterologous strains. Antibody responses to vaccine-homologous/heterologous strains persisted in all children 6 months following the booster vaccination. Conclusions. Prevaccination of young children with a clade 2 strain influenza A(H5N1) AS03-adjuvanted vaccine followed by heterologous booster vaccination boosted immune responses to the homologous strain and a related clade, with persistence for at least 6 months. The results support a prime-boost vaccination approach in young children for pandemic influenza preparedness. Clinical Trials Registration. NCT01323946. PMID:24973461

  12. Isolation of H5N6, H7N9 and H9N2 avian influenza A viruses from air sampled at live poultry markets in China, 2014 and 2015.

    Science.gov (United States)

    Zhou, Jie; Wu, Jie; Zeng, Xianqiao; Huang, Guofeng; Zou, Lirong; Song, Yingchao; Gopinath, Divya; Zhang, Xin; Kang, Min; Lin, Jinyan; Cowling, Benjamin J; Lindsley, William G; Ke, Changwen; Peiris, Joseph Sriyal Malik; Yen, Hui-Ling

    2016-09-01

    Zoonotic infections by avian influenza viruses occur at the human-poultry interface, but the modes of transmission have not been fully investigated. We assessed the potential for airborne and fomite transmission at live poultry markets in Guangzhou city and in Hong Kong Special Administrative Region (SAR), China, during 2014 and 2015. Viral genome and infectious avian influenza A viruses of H5N6, H7N9, and H9N2 subtypes were detected predominantly from particles larger or equal to 1 μm in diameter in the air sampled with cyclone-based bioaerosol samplers at the live poultry markets in Guangzhou. Influenza A(H9N2) viruses were ubiquitously isolated every month during the study period from air and environmental swabs, and different lineages of H9N2 virus were isolated from markets where chickens and minor land-based poultry were sold. The use of de-feathering devices increased the quantity of virus-laden airborne particles while market closure reduced the amount of such particles. The results highlight the possibility of airborne transmission of avian influenza viruses among poultry or from poultry to humans within such settings. This may explain epidemiological observations in which some patients with H7N9 infection reported being in markets but no direct contact with live poultry or poultry stalls. This article is copyright of The Authors, 2016.

  13. Acute necrotizing encephalopathy in a child with H1N1 influenza infection

    International Nuclear Information System (INIS)

    Lyon, Jane B.; Remigio, Cheryl; Milligan, Thomas; Deline, Carol

    2010-01-01

    Since the World Health Organization declared a global pandemic of novel influenza A H1N1 in June 2009, there has been a sustained rise in the number of cases of this strain of influenza. Although most cases are mild with complete and uneventful recovery, multiple cases of severe infection with complications including death have been reported. To the best of our knowledge, the majority of fatal outcomes in the United States have been related to pulmonary complications. We report a 12-year-old girl infected with influenza A H1N1 whose clinical course was complicated by rapid progressive neurologic deterioration and striking CT and MRI findings consistent with acute necrotizing encephalopathy (ANE). To our knowledge this has not been reported in the pediatric radiology literature. We hope this case will alert radiologists to this complication and familiarize radiologists with imaging findings that herald ANE. (orig.)

  14. Pathogenesis of H5N1 influenza virus infections in mice and ferret models differ between respiratory and digestive system exposure

    Science.gov (United States)

    Background. Epidemiological, clinical and laboratory data suggests H5N1 influenza viruses are transmitted through and predominantly affect the respiratory system of mammals. Some data suggests digestive system involvement. However, direct evidence of alimentary transmission and infection in mammal...

  15. Relative Efficacy of AS03-Adjuvanted Pandemic Influenza A(H1N1) Vaccine in Children: Results of a Controlled, Randomized Efficacy Trial

    Science.gov (United States)

    Nolan, Terry; Roy-Ghanta, Sumita; Montellano, May; Weckx, Lily; Ulloa-Gutierrez, Rolando; Lazcano-Ponce, Eduardo; Kerdpanich, Angkool; Safadi, Marco Aurélio Palazzi; Cruz-Valdez, Aurelio; Litao, Sandra; Lim, Fong Seng; de Los Santos, Abiel Mascareñas; Weber, Miguel Angel Rodriguez; Tinoco, Juan-Carlos; Mezerville, Marcela Hernandez-de; Faingezicht, Idis; Kosuwon, Pensri; Lopez, Pio; Borja-Tabora, Charissa; Li, Ping; Durviaux, Serge; Fries, Louis; Dubin, Gary; Breuer, Thomas; Innis, Bruce L.; Vaughn, David W.

    2014-01-01

    Background. The vaccine efficacy (VE) of 1 or 2 doses of AS03-adjuvanted influenza A(H1N1) vaccine relative to that of 2 doses of nonadjuvanted influenza A(H1N1) vaccine in children 6 months to <10 years of age in a multinational study conducted during 2010–2011. Methods. A total of 6145 children were randomly assigned at a ratio of 1:1:1 to receive 2 injections 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine at dose 1 and saline placebo at dose 2, 2 doses 21 days apart of A/California/7/2009(H1N1)-AS03 vaccine (the Ad2 group), or 2 doses 21 days apart of nonadjuvanted A/California/7/2009(H1N1) vaccine (the NAd2 group). Active surveillance for influenza-like illnesses continued from days 14 to 385. Nose and throat samples obtained during influenza-like illnesses were tested for A/California/7/2009(H1N1), using reverse-transcriptase polymerase chain reaction. Immunogenicity, reactogenicity, and safety were assessed. Results. There were 23 cases of confirmed 2009 pandemic influenza A(H1N1) (A[H1N1]pdm09) infection for the primary relative VE analysis. The VE in the Ad2 group relative to that in the NAd2 group was 76.8% (95% confidence interval, 18.5%–93.4%). The benefit of the AS03 adjuvant was demonstrated in terms of the greater immunogenicity observed in the Ad2 group, compared with the NAd2 group. Conclusion. The 4–8-fold antigen-sparing adjuvanted pandemic influenza vaccine demonstrated superior and clinically important prevention of A(H1N1)pdm09 infection, compared with nonadjuvanted vaccine, with no observed increase in medically attended or serious adverse events. These data support the use of adjuvanted influenza vaccines during influenza pandemics. Clinical Trials Registration. NCT01051661. PMID:24652494

  16. Pandemic influenza A (H1N1 2009: epidemiological analysis of cases in a tropical/semi-arid region of Brazil

    Directory of Open Access Journals (Sweden)

    Roberto da Justa Pires Neto

    2013-04-01

    Full Text Available Introduction The year 2009 marked the beginning of a pandemic caused by a new variant of influenza A (H1N1. After spreading through North America, the pandemic influenza virus (H1N1 2009 spread rapidly throughout the world. The aim of this study was to describe the clinical and epidemiological characteristics of cases of pandemic influenza in a tropical/semi-arid region of Brazil. Methods A retrospective study analyzed all suspected cases of pandemic influenza (H1N1 2009 reported in the Ceará State through the National Information System for Notifiable Diseases during the pandemic period between 28 April, 2009 and November 25, 2010. Results A total of 616 suspected cases were notified, 58 (9.4% in the containment phase and 558 (90.6% in the mitigation phase. Most cases were of affected young people resident in the City of Fortaleza, the largest urban center in the State of Ceará. The most frequent symptoms presented by the cases with confirmed infection were fever, cough, myalgia, arthralgia, and nasal congestion. Mortality rate was 0.0009/1,000 inhabitants and lethality was 5.6%. Deaths were observed only in the mitigation phase. Mortality rates were similar for both sexes but were higher in the age group under 5 years. Conclusions The study suggests that the influenza A (H1N1 pandemic in this tropical/semi-arid region had a lower magnitude when compared to states in the Southern and Southeastern regions of Brazil.

  17. Pandemic influenza 1918 H1N1 and 1968 H3N2 DNA vaccines induce cross-reactive immunity in ferrets against infection with viruses drifted for decades

    DEFF Research Database (Denmark)

    Bragstad, Karoline; Martel, Cyril; Thomsen, Joakim S.

    2011-01-01

    Please cite this paper as: Bragstad et al. (2010) Pandemic influenza 1918 H1N1 and 1968 H3N2 DNA vaccines induce cross-reactive immunity in ferrets against infection with viruses drifted for decades. Influenza and Other Respiratory Viruses 5(1), 13-23. Background Alternative influenza vaccines...... and vaccine production forms are needed as the conventional protein vaccines do not induce broad cross-reactivity against drifted strains. Furthermore, fast vaccine production is especially important in a pandemic situation, and broader vaccine reactivity would diminish the need for frequent change...... in the vaccine formulations. Objective In this study, we compared the ability of pandemic influenza DNA vaccines to induce immunity against distantly related strains within a subtype with the immunity induced by conventional trivalent protein vaccines against homologous virus challenge. Methods Ferrets were...

  18. Genomic and Phylogenetic Characterization of Novel, Recombinant H5N2 Avian Influenza Virus Strains Isolated from Vaccinated Chickens with Clinical Symptoms in China

    Directory of Open Access Journals (Sweden)

    Huaiying Xu

    2015-02-01

    Full Text Available Infection of poultry with diverse lineages of H5N2 avian influenza viruses has been documented for over three decades in different parts of the world, with limited outbreaks caused by this highly pathogenic avian influenza virus. In the present study, three avian H5N2 influenza viruses, A/chicken/Shijiazhuang/1209/2013, A/chicken/Chiping/0321/2014, and A/chicken/Laiwu/0313/2014, were isolated from chickens with clinical symptoms of avian influenza. Complete genomic and phylogenetic analyses demonstrated that all three isolates are novel recombinant viruses with hemagglutinin (HA and matrix (M genes derived from H5N1, and remaining genes derived from H9N2-like viruses. The HA cleavage motif in all three strains (PQIEGRRRKR/GL is characteristic of a highly pathogenic avian influenza virus strain. These results indicate the occurrence of H5N2 recombination and highlight the importance of continued surveillance of the H5N2 subtype virus and reformulation of vaccine strains.

  19. Divergent genetic evolution of hemagglutinin in influenza A H1N1 and A H1N2 subtypes isolated in the south-France since the winter of 2001-2002.

    Science.gov (United States)

    Al Faress, Shaker; Cartet, Gaëlle; Ferraris, Olivier; Norder, Helene; Valette, Martine; Lina, Bruno

    2005-07-01

    Influenza A viruses are divided into subtypes based on their hemagglutinin (H1 to H15) and neuraminidase (N1 to N9) glycoproteins. Of these, three A subtypes H1N1, H3N2 and H1N2 circulate in the human population. Influenza A viruses display a high antigenic variability called "antigenic drift" which allows the virus to escape antibody neutralization. Evaluate the mutations apparition that might predict a divergent antigenic evolution of hemagglutinin in influenza A H1N1 and A H1N2 viruses. During the three winters of 2001-2002 to 2003-2004, 58 A H1N1 and 23 A H1N2 subtypes have been isolated from patients with influenza-like illness in the south of France. The HA1 region was analyzed by RT-PCR and subsequently sequenced to compare the HA1 genetic evolution of influenza A H1N1 and A H1N2 subtypes. Our results showed that 28 amino acid substitutions have accumulated in the HA1 region since the circulation of A/New Caledonia/20/99-like viruses in France. Of these, fifteen were located in four antigenic sites (B, C, D and E). Six of them were observed only in the A H1N2 isolates, six only in the A H1N1 isolates and three in both subtypes. Furthermore, nine of twenty two A H1N2 isolates from the winter of 2002-2003 shared a T90A amino acid change which has not been observed in any A H1N1 isolate; resulting in the introduction of a new glycosylation site close to the antigenic site E. This might mask some antigenic E determinants and therefore, modify the A H1N2 antigenicity. The divergent genetic evolution of hemagglutinin may ultimately lead to a significant different antigenicity between A H1N1 and A H1N2 subtypes that would require the introduction of a new subtype in the vaccine batches.

  20. Influenza A(H6N1) Virus in Dogs, Taiwan

    Science.gov (United States)

    Lin, Hui-Ting; Wang, Ching-Ho; Chueh, Ling-Ling; Su, Bi-Ling

    2015-01-01

    We determined the prevalence of influenza A virus in dogs in Taiwan and isolated A/canine/Taiwan/E01/2014. Molecular analysis indicated that this isolate was closely related to influenza A(H6N1) viruses circulating in Taiwan and harbored the E627K substitution in the polymerase basic 2 protein, which indicated its ability to replicate in mammalian species. PMID:26583707

  1. Spatial modeling of wild bird risk factors to investigate highly pathogenic A(H5N1) avian influenza virus transmission

    Science.gov (United States)

    Prosser, Diann J.; Hungerford, Laura L.; Erwin, R. Michael; Ottinger, Mary Ann; Takekawa, John Y.; Newman, Scott H.; Xiao, Xianming; Ellis, Erie C.

    2016-01-01

    One of the longest-persisting avian influenza viruses in history, highly pathogenic avian influenza virus (HPAIV) A(H5N1), continues to evolve after 18 years, advancing the threat of a global pandemic. Wild waterfowl (family Anatidae), are reported as secondary transmitters of HPAIV, and primary reservoirs for low-pathogenic avian influenza viruses, yet spatial inputs for disease risk modeling for this group have been lacking. Using GIS and Monte Carlo simulations, we developed geospatial indices of waterfowl abundance at 1 and 30 km resolutions and for the breeding and wintering seasons for China, the epicenter of H5N1. Two spatial layers were developed: cumulative waterfowl abundance (WAB), a measure of predicted abundance across species, and cumulative abundance weighted by H5N1 prevalence (WPR), whereby abundance for each species was adjusted based on prevalence values then totaled across species. Spatial patterns of the model output differed between seasons, with higher WAB and WPR in the northern and western regions of China for the breeding season and in the southeast for the wintering season. Uncertainty measures indicated highest error in southeastern China for both WAB and WPR. We also explored the effect of resampling waterfowl layers from 1 km to 30 km resolution for multi-scale risk modeling. Results indicated low average difference (less than 0.16 and 0.01 standard deviations for WAB and WPR, respectively), with greatest differences in the north for the breeding season and southeast for the wintering season. This work provides the first geospatial models of waterfowl abundance available for China. The indices provide important inputs for modeling disease transmission risk at the interface of poultry and wild birds. These models are easily adaptable, have broad utility to both disease and conservation needs, and will be available to the scientific community for advanced modeling applications.

  2. Military and Military Medical Support in Highly Pathogenic Avian Influenza (HPAI/H5N1) Pandemic Scenario

    International Nuclear Information System (INIS)

    Taleski, V.

    2007-01-01

    Avian influenza (Bird flu) is a highly contagious viral disease affecting mainly chickens, turkeys, ducks, other birds and mammals. Reservoirs for HPAI /H5N1 virus are shore birds and waterfowl (asymptomatic, excrete virus in feces for a long periods of time), live bird markets and commercial swine facilities. Virus tends to cycle between pigs and birds. HPAI (H5N1) virus is on every 'top ten' list available for potential agricultural bio-weapon agents. The threat of a HPAI/H5N1 pandemic is a definitively global phenomenon and the response must be global. A number of National plans led to various measures of preventing and dealing with epidemics/pandemics. Lessons learned form the pandemic history indicated essential role of military and military medical support to civil authorities in a crisis situation. Based on International Military Medical Avian Influenza Pandemic workshop (Vienna 2006), an expected scenario would involve 30-50% outpatients, 20-30% hospital admission, 2-3% deaths, 10-20% complicated cases. Activities of civil hospital may be reduced by 50%. Benefits of military support could be in: Transportation of patients (primarily by air); Mass vaccination and provision of all other preventive measures (masks, Tamiflu); Restriction of movements; Infection control of health care facilities; Field hospitals for triage and quarantine, military barracks to treat milder cases and military hospitals for severe cases; Deal with corpses; Stockpiling (vaccines, antiviral, antibiotics, protective equipment, supplies); Training; Laboratories; Ensure public safety, etc. With the aim of minimizing the risk of a pandemic spread by means of rapid and uncomplicated cooperation, an early warning system has to be established to improve surveillance, improve international contacts (WHO, ECDC, CDC), establish Platform for sharing information, close contacts of national and international military and civilian surveillance networks and databases, cooperation between military

  3. Migration of whooper swans and outbreaks of highly pathogenic avian influenza H5N1 virus in eastern Asia.

    Science.gov (United States)

    Newman, Scott H; Iverson, Samuel A; Takekawa, John Y; Gilbert, Martin; Prosser, Diann J; Batbayar, Nyambyar; Natsagdorj, Tseveenmyadag; Douglas, David C

    2009-05-28

    Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1) requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp.) has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus) with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer) and in habitats (areas of natural vegetation) where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks) at or near their breeding grounds.

  4. Genetic and biological characterisation of an avian-like H1N2 swine influenza virus generated by reassortment of circulating avian-like H1N1 and H3N2 subtypes in Denmark

    DEFF Research Database (Denmark)

    Trebbien, Ramona; Bragstad, Karoline; Larsen, Lars Erik

    2013-01-01

    BACKGROUND: The influenza A virus subtypes H1N1, H1N2 and H3N2 are the most prevalent subtypes in swine. In 2003, a reassorted H1N2 swine influenza virus (SIV) subtype appeared and became prevalent in Denmark. In the present study, the reassortant H1N2 subtype was characterised genetically...... and the infection dynamics compared to an “avian-like” H1N1 virus by an experimental infection study. METHODS: Sequence analyses were performed of the H1N2 virus. Two groups of pigs were inoculated with the reassortant H1N2 virus and an “avian-like” H1N1 virus, respectively, followed by inoculation...... with the opposite subtype four weeks later. Measurements of HI antibodies and acute phase proteins were performed. Nasal virus excretion and virus load in lungs were determined by real-time RT-PCR. RESULTS: The phylogenetic analysis revealed that the reassorted H1N2 virus contained a European “avian-like” H1-gene...

  5. Patient reported outcome data following influenza A (H1N1p vaccination in the 2009–2010 season: web-based and telephone evaluation

    Directory of Open Access Journals (Sweden)

    Wade AG

    2011-10-01

    Full Text Available Alan G Wade1, Gordon M Crawford1, Neil Pumford1, Alex McConnachie21Patients Direct, 3 Todd Campus, Glasgow, UK; 2Robertson Centre for Biostatistics, University of Glasgow, Glasgow, UKBackground: There has been worldwide interest in the safety of the pandemic influenza A (H1N1p vaccines, although limited data are available from the vaccine recipients’ perspective. This evaluation was designed to collect data from people who had received an influenza vaccination during the 2009–2010 season using a web-based data collection tool supplemented by telephone reporting (PROBE.Methods: People scheduled to receive the influenza A (H1N1p or seasonal influenza vaccines were recruited through media advertising and campaigns throughout the West of Scotland. Vaccine recipients participated in the evaluation by answering demographic and side effect questions using PROBE methodology on the day of the immunization, after 3 days, 8 days, 6 weeks, 12 weeks, and 26 weeks.Results: A total of 1103 vaccine recipients including 134 young children (0–4 years participated in the evaluation; 694 (63% received H1N1p vaccine only, 135 (12% seasonal vaccine only, 224 (20% both H1N1p and seasonal vaccines, and 50 (5% received H1N1p or seasonal vaccine with a non-influenza vaccine (eg, travel or pneumococcal. Overall, 42% of recipients reported experiencing a side effect after their baseline vaccination; the most commonly reported were general and arm side effects (>20%. Injection site discomfort/pain and flu-like symptoms were reported by 57% and 24% of recipients, respectively. A significantly higher proportion of the 960 H1N1p vaccine recipients experienced a side effect (44% vs 27%, P < 0.001 or injection site discomfort/pain (61% vs 26%, P < 0.001 than those receiving seasonal influenza vaccines. Female sex and H1N1p vaccination were associated with a significantly higher risk of injection site discomfort/pain, whereas the 70+ age group was associated with a

  6. Whole-Genome Characterization of a Novel Human Influenza A(H1N2) Virus Variant, Brazil.

    Science.gov (United States)

    Resende, Paola Cristina; Born, Priscila Silva; Matos, Aline Rocha; Motta, Fernando Couto; Caetano, Braulia Costa; Debur, Maria do Carmo; Riediger, Irina Nastassja; Brown, David; Siqueira, Marilda M

    2017-01-01

    We report the characterization of a novel reassortant influenza A(H1N2) virus not previously reported in humans. Recovered from a a pig farm worker in southeast Brazil who had influenza-like illness, this virus is a triple reassortant containing gene segments from subtypes H1N2 (hemagglutinin), H3N2 (neuraminidase), and pandemic H1N1 (remaining genes).

  7. Biosecurity and Circulation of Influenza A (H5N1) Virus in Live-Bird Markets in Bangladesh, 2012.

    Science.gov (United States)

    Biswas, P K; Giasuddin, M; Nath, B K; Islam, M Z; Debnath, N C; Yamage, M

    2017-06-01

    Bangladesh has been considered as one of the five countries endemic with highly pathogenic avian influenza A subtype H5N1 (HPAI H5N1). Live-bird markets (LBMs) in south Asian countries are believed to play important roles in the transmission of HPAI H5N1 and others due to its central location as a hub of the poultry trading. Food and Agriculture Organization (FAO) of the United Nations has been promoting improved biosecurity in LBMs in Bangladesh. In 2012, by enrolling 32 large LBMs: 10 with FAO interventions and 22 without assistance, we assessed the virus circulation in the selected LBMs by applying standard procedures to investigate market floors, poultry stall floors, poultry-holding cases and slaughter areas and the overall biosecurity using a questionnaire-based survey. Relative risk (RR) was examined to compare the prevalence of HPAI H5N1 in the intervened and non-intervened LBMs. The measures practised in significantly more of the FAO-intervened LBMs included keeping of slaughter remnants in a closed container; decontamination of poultry vehicles at market place; prevention of crows' access to LBM, market/floor cleaning by market committee; wet cleaning; disinfection of floor/poultry stall after cleaning; and good supply of clean water at market (P Bangladesh regardless of interventions, albeit at lower levels than in other endemic countries. © 2015 Blackwell Verlag GmbH.

  8. No evidence of transmission of H5N1 highly pathogenic avian influenza to humans after unprotected contact with infected wild swans.

    Science.gov (United States)

    Wallensten, A; Salter, M; Bennett, S; Brown, I; Hoschler, K; Oliver, I

    2010-02-01

    Highly pathogenic avian influenza (HPAI) subtype H5N1 remains a public health threat as long as it circulates in wild and domestic birds. Information on the transmissibility of H5N1 HPAI from wild birds is needed for evidence-based public health advice. We investigated if transmission of H5N1 HPAI had taken place in people that had unprotected contact with infected wild mute swans during an incident at the Abbotsbury Swannery in Dorset, England. Thirteen people who had been exposed to infected swans were contacted and actively followed up for symptoms. Serology was taken after 30 days. We did not find evidence of transmission of H5N1 HPAI to humans during the incident. The incident provided a rare opportunity to study the transmissibility of the virus from wild birds to humans.

  9. Primary study on the lesions and specific proteins in BEAS-2B cells induced with the 2009 A (H1N1) influenza virus.

    Science.gov (United States)

    Fang, Shisong; Zhang, Kaining; Wang, Ting; Wang, Xin; Lu, Xing; Peng, Bo; Wu, Weihua; Zhang, Ran; Chen, Shiju; Zhang, Renli; Xue, Hong; Yu, Muhua; Cheng, Jinquan

    2014-12-01

    In order to investigate the lesions and proteins with differential expression in cells infected with the 2009 A (H1N1) virus and to determine the specific proteins involved in cell damage, the present study has been performed. BEAS-2B cells were infected with the 2009 A (H1N1) influenza virus or the seasonal H1N1 influenza virus for 12, 24, 48, and 72 h, and cell cycle and apoptosis were analyzed with flow cytometry. Total cellular proteins were extracted and underwent two-dimensional gel electrophoresis. The differentially expressed proteins underwent mass spectrometry for identification. The results showed that after 12 h, cells infected with the virus strain sourced from severe cases had the highest apoptosis rate (P cells infected with the virus strain sourced from fatal cases and severe cases had the highest apoptosis rate (P cells infected with virus strains from fatal cases and ordinary cases had the highest apoptosis rate (P cell cycle arrest mainly at the G0/G1 phase. Eighteen differentially expressed proteins were identified, including galectin-1, cofilin-1, protein DJ-1, proteasome subunit α type-5, macrophage migration inhibitory factor, translationally controlled tumor protein, profilin 1, and interferon α-2. Galectin-1 was specifically observed in BEAS-2B infected with 2009 A (H1N1) influenza viruses, and cofilin-1 was specifically observed in BEAS-2B cells in the late stage of 2009 A (H1N1) influenza virus infection. In conclusion, differential effects of the 2009 A (H1N1) influenza virus and seasonal H1N1 influenza virus were identified on the cell cycle and apoptosis, and galectin-1 may play a role in cell apoptosis induced by 2009 A (H1N1) influenza virus.

  10. Fatal H5N6 Avian Influenza Virus Infection in a Domestic Cat and Wild Birds in China.

    Science.gov (United States)

    Yu, Zhijun; Gao, Xiaolong; Wang, Tiecheng; Li, Yanbing; Li, Yongcheng; Xu, Yu; Chu, Dong; Sun, Heting; Wu, Changjiang; Li, Shengnan; Wang, Haijun; Li, Yuanguo; Xia, Zhiping; Lin, Weishi; Qian, Jun; Chen, Hualan; Xia, Xianzhu; Gao, Yuwei

    2015-06-02

    H5N6 avian influenza viruses (AIVs) may pose a potential human risk as suggested by the first documented naturally-acquired human H5N6 virus infection in 2014. Here, we report the first cases of fatal H5N6 avian influenza virus (AIV) infection in a domestic cat and wild birds. These cases followed human H5N6 infections in China and preceded an H5N6 outbreak in chickens. The extensive migration routes of wild birds may contribute to the geographic spread of H5N6 AIVs and pose a risk to humans and susceptible domesticated animals, and the H5N6 AIVs may spread from southern China to northern China by wild birds. Additional surveillance is required to better understand the threat of zoonotic transmission of AIVs.

  11. Molecular epidemiology of influenza A(H1N1PDM09 hemagglutinin gene circulating in São Paulo State , Brazil: 2016 anticipated influenza season

    Directory of Open Access Journals (Sweden)

    Katia Corrêa de Oliveira Santos

    Full Text Available ABSTRACT Compared to previous years, seasonal influenza activity commenced early in São Paulo State, Brazil, Southern hemisphere during the 2016 year. In order to investigate the genetic pattern of influenza A(H1N1pdm09 in the State of Sao Paulo a total of 479 respiratory samples, collected in January by Sentinel Surveillance Units, were screened by real-time RT-PCR. A total of 6 Influenza viruses A(H1N1pdm09 presenting ct values ≤ 30 were sequenced following phylogenetic analysis. The present study identified the circulation of the new 6B.1 subgroup (A/Sao Paulo/10-118/2016 and A/Sao Paulo/3032/2016. In addition, influenza A(H1N1pdm09 group 6B has also been identified during January in the State of Sao Paulo. Despite amino acid changes and changes in potential glycosylation motifs, 6B.1 viruses were well inhibited by the reference ferret antiserum against A/California/07/2009 virus, the A(H1N1pdm09 component of the vaccine for the 2016 influenza season.

  12. Southward autumn migration of waterfowl facilitates cross-continental transmission of the highly pathogenic avian influenza H5N1 virus

    Science.gov (United States)

    Xu, Yanjie; Gong, Peng; Wielstra, Ben; Si, Yali

    2016-08-01

    The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration routes. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration.

  13. Safety and immunogenicity of a modified-vaccinia-virus-Ankara-based influenza A H5N1 vaccine: a randomised, double-blind phase 1/2a clinical trial.

    Science.gov (United States)

    Kreijtz, Joost H C M; Goeijenbier, Marco; Moesker, Fleur M; van den Dries, Lennert; Goeijenbier, Simone; De Gruyter, Heidi L M; Lehmann, Michael H; Mutsert, Gerrie de; van de Vijver, David A M C; Volz, Asisa; Fouchier, Ron A M; van Gorp, Eric C M; Rimmelzwaan, Guus F; Sutter, Gerd; Osterhaus, Albert D M E

    2014-12-01

    Modified vaccinia virus Ankara (MVA) is a promising viral vector platform for the development of an H5N1 influenza vaccine. Preclinical assessment of MVA-based H5N1 vaccines showed their immunogenicity and safety in different animal models. We aimed to assess the safety and immunogenicity of the MVA-haemagglutinin-based H5N1 vaccine MVA-H5-sfMR in healthy individuals. In a single-centre, double-blind phase 1/2a study, young volunteers (aged 18-28 years) were randomly assigned with a computer-generated list in equal numbers to one of eight groups and were given one injection or two injections intramuscularly at an interval of 4 weeks of a standard dose (10(8) plaque forming units [pfu]) or a ten times lower dose (10(7) pfu) of the MVA-H5-sfMR (vector encoding the haemagglutinin gene of influenza A/Vietnam/1194/2004 virus [H5N1 subtype]) or MVA-F6-sfMR (empty vector) vaccine. Volunteers and physicians who examined and administered the vaccine were masked to vaccine assignment. Individuals who received the MVA-H5-sfMR vaccine were eligible for a booster immunisation 1 year after the first immunisation. Primary endpoint was safety. Secondary outcome was immunogenicity. The trial is registered with the Dutch Trial Register, number NTR3401. 79 of 80 individuals who were enrolled completed the study. No serious adverse events were identified. 11 individuals reported severe headache and lightheadedness, erythema nodosum, respiratory illness (accompanied by influenza-like symptoms), sore throat, or injection-site reaction. Most of the volunteers had one or more local (itch, pain, redness, and swelling) and systemic reactions (rise in body temperature, headache, myalgia, arthralgia, chills, malaise, and fatigue) after the first, second, and booster immunisations. Individuals who received the 10(7) dose had fewer systemic reactions. The MVA-H5-sfMR vaccine at 10(8) pfu induced significantly higher antibody responses after one and two immunisations than did 10(7) pfu when

  14. Asymptomatic ratio for seasonal H1N1 influenza infection among schoolchildren in Taiwan.

    Science.gov (United States)

    Hsieh, Ying-Hen; Tsai, Chen-An; Lin, Chien-Yu; Chen, Jin-Hua; King, Chwan-Chuen; Chao, Day-Yu; Cheng, Kuang-Fu

    2014-02-12

    Studies indicate that asymptomatic infections do indeed occur frequently for both seasonal and pandemic influenza, accounting for about one-third of influenza infections. Studies carried out during the 2009 pH1N1 pandemic have found significant antibody response against seasonal H1N1 and H3N2 vaccine strains in schoolchildren receiving only pandemic H1N1 monovalent vaccine, yet reported either no symptoms or only mild symptoms. Serum samples of 255 schoolchildren, who had not received vaccination and had pre-season HI Ab serotiters definition of Fever + (cough or sore throat or nose) + ( headache or pain or fatigue). Asymptomatic ratio for children is found to be substantially higher than that of the general population in literature. In providing reasonable quantification of the asymptomatic infected children spreading pathogens to others in a seasonal epidemic or a pandemic, our estimates of symptomatic ratio of infected children has important clinical and public health implications.

  15. Dynamic gene expression analysis in a H1N1 influenza virus mouse pneumonia model.

    Science.gov (United States)

    Bao, Yanyan; Gao, Yingjie; Shi, Yujing; Cui, Xiaolan

    2017-06-01

    H1N1, a major pathogenic subtype of influenza A virus, causes a respiratory infection in humans and livestock that can range from a mild infection to more severe pneumonia associated with acute respiratory distress syndrome. Understanding the dynamic changes in the genome and the related functional changes induced by H1N1 influenza virus infection is essential to elucidating the pathogenesis of this virus and thereby determining strategies to prevent future outbreaks. In this study, we filtered the significantly expressed genes in mouse pneumonia using mRNA microarray analysis. Using STC analysis, seven significant gene clusters were revealed, and using STC-GO analysis, we explored the significant functions of these seven gene clusters. The results revealed GOs related to H1N1 virus-induced inflammatory and immune functions, including innate immune response, inflammatory response, specific immune response, and cellular response to interferon-beta. Furthermore, the dynamic regulation relationships of the key genes in mouse pneumonia were revealed by dynamic gene network analysis, and the most important genes were filtered, including Dhx58, Cxcl10, Cxcl11, Zbp1, Ifit1, Ifih1, Trim25, Mx2, Oas2, Cd274, Irgm1, and Irf7. These results suggested that during mouse pneumonia, changes in the expression of gene clusters and the complex interactions among genes lead to significant changes in function. Dynamic gene expression analysis revealed key genes that performed important functions. These results are a prelude to advancements in mouse H1N1 influenza virus infection biology, as well as the use of mice as a model organism for human H1N1 influenza virus infection studies.

  16. Estimating the disease burden of 2009 pandemic influenza A(H1N1 from surveillance and household surveys in Greece.

    Directory of Open Access Journals (Sweden)

    Vana Sypsa

    Full Text Available The aim of this study was to assess the disease burden of the 2009 pandemic influenza A(H1N1 in Greece.Data on influenza-like illness (ILI, collected through cross-sectional nationwide telephone surveys of 1,000 households in Greece repeated for 25 consecutive weeks, were combined with data from H1N1 virologic surveillance to estimate the incidence and the clinical attack rate (CAR of influenza A(H1N1. Alternative definitions of ILI (cough or sore throat and fever>38°C [ILI-38] or fever 37.1-38°C [ILI-37] were used to estimate the number of symptomatic infections. The infection attack rate (IAR was approximated using estimates from published studies on the frequency of fever in infected individuals. Data on H1N1 morbidity and mortality were used to estimate ICU admission and case fatality (CFR rates. The epidemic peaked on week 48/2009 with approximately 750-1,500 new cases/100,000 population per week, depending on ILI-38 or ILI-37 case definition, respectively. By week 6/2010, 7.1%-15.6% of the population in Greece was estimated to be symptomatically infected with H1N1. Children 5-19 years represented the most affected population group (CAR:27%-54%, whereas individuals older than 64 years were the least affected (CAR:0.6%-2.2%. The IAR (95% CI of influenza A(H1N1 was estimated to be 19.7% (13.3%, 26.1%. Per 1,000 symptomatic cases, based on ILI-38 case definition, 416 attended health services, 108 visited hospital emergency departments and 15 were admitted to hospitals. ICU admission rate and CFR were 37 and 17.5 per 100,000 symptomatic cases or 13.4 and 6.3 per 100,000 infections, respectively.Influenza A(H1N1 infected one fifth and caused symptomatic infection in up to 15% of the Greek population. Although individuals older than 65 years were the least affected age group in terms of attack rate, they had 55 and 185 times higher risk of ICU admission and CFR, respectively.

  17. Highly pathogenic avian influenza (H5N1: pathways of exposure at the animal-human interface, a systematic review.

    Directory of Open Access Journals (Sweden)

    Maria D Van Kerkhove

    Full Text Available BACKGROUND: The threat posed by highly pathogenic avian influenza A H5N1 viruses to humans remains significant, given the continued occurrence of sporadic human cases (499 human cases in 15 countries with a high case fatality rate (approximately 60%, the endemicity in poultry populations in several countries, and the potential for reassortment with the newly emerging 2009 H1N1 pandemic strain. Therefore, we review risk factors for H5N1 infection in humans. METHODS AND FINDINGS: Several epidemiologic studies have evaluated the risk factors associated with increased risk of H5N1 infection among humans who were exposed to H5N1 viruses. Our review shows that most H5N1 cases are attributed to exposure to sick poultry. Most cases are sporadic, while occasional limited human-to-human transmission occurs. The most commonly identified factors associated with H5N1 virus infection included exposure through contact with infected blood or bodily fluids of infected poultry via food preparation practices; touching and caring for infected poultry; [corrected] exposure to H5N1 via swimming or bathing in potentially virus laden ponds; and exposure to H5N1 at live bird markets. CONCLUSIONS: Research has demonstrated that despite frequent and widespread contact with poultry, transmission of the H5N1 virus from poultry to humans is rare. Available research has identified several risk factors that may be associated with infection including close direct contact with poultry and transmission via the environment. However, several important data gaps remain that limit our understanding of the epidemiology of H5N1 in humans. Although infection in humans with H5N1 remains rare, human cases continue to be reported and H5N1 is now considered endemic among poultry in parts of Asia and in Egypt, providing opportunities for additional human infections and for the acquisition of virus mutations that may lead to more efficient spread among humans and other mammalian species

  18. [Results of clinical trials on reactogenicity, safety, and immunogenicity of influenza allantoic intranasal live vaccine "Ultragrivac" (type A/H5N2)].

    Science.gov (United States)

    Mazurkova, N A; Ryndiuk, N N; Shishkina, L N; Ternovoĭ, V A; Tumanov, Iu V; Bulychev, L E; Skarnovich, M O; Kabanov, A S; Panchenko, S G; Aleĭnikov, R P; Il'ina, T N; Kuzubov, V I; Mel'nikov, S Ia; Mironov, A N; Korovkin, S A; Sergeev, A N; Drozdov, I G

    2010-01-01

    Results of phase II of a clinical trial of the influenza allantoic intranasal live vaccine "Ultragrivac" (type A/H5N2) are presented. The vaccine was developed based on strain /17/Duck/Potsdam/86/92 H5N2 [17/H5] - reassortant of two viruses, /Leningrad/134/17/57 (H2N2) and /Duck/Potsdam/1402-86 (H5N2), obtained from the Virology Department, St. Petersburg Institute of Experimental Medicine.Two schemes of immunization (with revaccination on days 10 and 21) were used. Evaluation of vaccine immunogenicity included determination of local, cellular and humoral immunity. A significant rise in the level of secretory IgA in the nasal cavity of vaccinated volunteers (with revaccination on days 10 and 21) was documented after application of the vaccine. The postvaccination humoral immune response was estimated from the level of significant (4-fold and more) antibody seroconversions, geometric mean titers of antibodies to two strains of influenza virus /17/Duck/Potsdam/86/92 H5N2 [17/H5] and /Chicken/Suzdalka/Nov-11/2005 (H5N1), and their incremental rate. Results of measurement of antibody titers in hemagglutination-inhibition assay are presented, with two antigens being used to analyse all serum samples from volunteers twice vaccinated with influenza vaccine "Ultragrivac" at 10 and 21 day intervals. Result of phase II of this clinical study show that influenza allantoic intranasal live vaccine "Ultragrivac" is nonreactogenic and safe for both vaccinated and surrounding individuals. Moreover, it is sufficiently immunogenic with respect not only to homologous virus A(H5N2) but also to the A(H5N1) strain.

  19. Pathology of natural infections by H5N1 highly pathogenic avian influenza virus in mute (Cygnus olor) and whooper (Cygnus cygnus) swans.

    Science.gov (United States)

    Teifke, J P; Klopfleisch, R; Globig, A; Starick, E; Hoffmann, B; Wolf, P U; Beer, M; Mettenleiter, T C; Harder, T C

    2007-03-01

    Mortality in wild aquatic birds due to infection with highly pathogenic avian influenza viruses (HPAIV) is a rare event. During the recent outbreak of highly pathogenic avian influenza in Germany, mortality due to H5N1 HPAIV was observed among mute and whooper swans as part of a rapid spread of this virus. In contrast to earlier reports, swans appeared to be highly susceptible and represented the mainly affected species. We report gross and histopathology and distribution of influenza virus antigen in mute and whooper swans that died after natural infection with H5N1 HPAIV. At necropsy, the most reliable lesions were multifocal hemorrhagic necrosis in the pancreas, pulmonary congestion and edema, and subepicardial hemorrhages. Major histologic lesions were acute pancreatic necrosis, multifocal necrotizing hepatitis, and lymphoplasmacytic encephalitis with neuronal necrosis. Adrenals displayed consistently scattered cortical and medullary necrosis. In spleen and Peyer's patches, mild lymphocyte necrosis was present. Immunohistochemical demonstration of HPAIV nucleoprotein in pancreas, adrenals, liver, and brain was strongly consistent with histologic lesions. In the brain, a large number of neurons and glial cells, especially Purkinje cells, showed immunostaining. Occasionally, ependymal cells of the spinal cord were also positive. In the lungs, influenza virus antigen was identified in a few endothelial cells but not within pneumocytes. The infection of the central nervous system supports the view that the neurotropism of H5N1 HPAIV leads to nervous disturbances with loss of orientation. More investigations are necessary to clarify the mechanisms of the final circulatory failure, lung edema, and rapid death of the swans.

  20. A Historical Perspective of Influenza A(H1N2) Virus

    OpenAIRE

    Komadina, Naomi; McVernon, Jodie; Hall, Robert; Leder, Karin

    2014-01-01

    The emergence and transition to pandemic status of the influenza A(H1N1)A(H1N1)pdm09) virus in 2009 illustrated the potential for previously circulating human viruses to re-emerge in humans and cause a pandemic after decades of circulating among animals. Within a short time of the initial emergence of A(H1N1)pdm09 virus, novel reassortants were isolated from swine. In late 2011, a variant (v) H3N2 subtype was isolated from humans, and by 2012, the number of persons infected began to increase ...

  1. Avian influenza A virus subtype H5N2 in a red-lored Amazon parrot.

    Science.gov (United States)

    Hawkins, Michelle G; Crossley, Beate M; Osofsky, Anna; Webby, Richard J; Lee, Chang-Won; Suarez, David L; Hietala, Sharon K

    2006-01-15

    A 3-month-old red-lored Amazon parrot (Amazona autumnalis autumnalis) was evaluated for severe lethargy. Avian influenza virus hemagglutinin subtype H5N2 with low pathogenicity was characterized by virus isolation, real-time reverse transcriptase PCR assay, chicken intravenous pathogenicity index, and reference sera. The virus was also determined to be closely related to a virus lineage that had been reported only in Mexico and Central America. The chick was admitted to the hospital and placed in quarantine. Supportive care treatment was administered. Although detection of H5 avian influenza virus in birds in the United States typically results in euthanasia of infected birds, an alternative strategy with strict quarantine measures and repeated diagnostic testing was used. The chick recovered from the initial clinical signs after 4 days and was released from quarantine 9 weeks after initial evaluation after 2 consecutive negative virus isolation and real-time reverse transcriptase PCR assay results. To the authors' knowledge, this is the first report of H5N2 avian influenza A virus isolated from a psittacine bird and represents the first introduction of this virus into the United States, most likely by illegal importation of psittacine birds. Avian influenza A virus should be considered as a differential diagnosis for clinical signs of gastrointestinal tract disease in psittacine birds, especially in birds with an unknown history of origin. Although infection with avian influenza virus subtype H5 is reportable, destruction of birds is not always required.

  2. Pandemic influenza A/H1N1 virus incursion into Africa: countries ...

    African Journals Online (AJOL)

    Pandemic influenza A/H1N1 virus incursion into Africa: countries, hosts and ... features are important for planning control measures between countries and to ... in humans, infections in pigs earlier reported in America, Europe and Asia were ...

  3. Pathology of whooper swans (Cygnus cygnus) infected with H5N1 avian influenza virus in Akita, Japan, in 2008.

    Science.gov (United States)

    Ogawa, Shuji; Yamamoto, Yu; Yamada, Manabu; Mase, Masaji; Nakamura, Kikuyasu

    2009-10-01

    Two (1 adult and 1 young bird) of 4 H5N1-highly-pathogenic-avian-influenza (HPAI)-virus-infected whooper swans in Akita, Japan, in 2008 were investigated pathologically. Macroscopically, white spots with hemorrhages were scattered in the pancreas in the adult bird. Histologically, the adult bird had severe necrotizing pancreatitis and mild nonpurulent encephalitis. The young bird had severe nonpurulent encephalitis and nonpurulent enteric ganglionitis, and intestinal venous wall thickening. Virus antigens were detected in the lesions of pancreatitis in the adult bird and of encephalitis in adult and young birds. These findings suggest that the swans died or became moribund due to neurological disorders and necrotizing pancreatitis caused by H5N1 HPAI virus infection.

  4. Experimental infection of a North American raptor, American Kestrel (Falco sparverius, with highly pathogenic avian influenza virus (H5N1.

    Directory of Open Access Journals (Sweden)

    Jeffrey S Hall

    2009-10-01

    Full Text Available Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV subtype H5N1. Should HPAIV (H5N1 reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1 infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1. All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1 is introduced into North America.

  5. Role for migratory wild birds in the global spread of avian influenza H5N8

    Science.gov (United States)

    ,; Ip, Hon S.

    2016-01-01

    Avian influenza viruses affect both poultry production and public health. A subtype H5N8 (clade 2.3.4.4) virus, following an outbreak in poultry in South Korea in January 2014, rapidly spread worldwide in 2014–2015. Our analysis of H5N8 viral sequences, epidemiological investigations, waterfowl migration, and poultry trade showed that long-distance migratory birds can play a major role in the global spread of avian influenza viruses. Further, we found that the hemagglutinin of clade 2.3.4.4 virus was remarkably promiscuous, creating reassortants with multiple neuraminidase subtypes. Improving our understanding of the circumpolar circulation of avian influenza viruses in migratory waterfowl will help to provide early warning of threats from avian influenza to poultry, and potentially human, health.

  6. Influenza A (H1N1) pneumonia: HRCT findings

    Energy Technology Data Exchange (ETDEWEB)

    Amorim, Viviane Brandao; Rodrigues, Rosana Souza; Barreto, Miriam Menna; Marchiori, Edson, E-mail: edmarchiori@gmail.com [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil); Zanetti, Glaucia [Escola de Medicina de Petropolis, RJ (Brazil); Hochhegger, Bruno [Santa Casa de Misericordia de Porto Alegre, RS (Brazil)

    2013-11-01

    Objective: to describe aspects found on HRCT scans of the chest in patients infected with the influenza A (H1N1) virus. Methods: we retrospectively analyzed the HRCT scans of 71 patients (38 females and 33 males) with H1N1 infection, confirmed through laboratory tests, between July and September of 2009. The HRCT scans were interpreted by two thoracic radiologists independently, and in case of disagreement, the decisions were made by consensus. Results: the most common HRCT findings were ground-glass opacities (85%), consolidation (64%), or a combination of ground-glass opacities and consolidation (58%). Other findings were airspace nodules (25%), bronchial wall thickening (25%), interlobular septal thickening (21%), crazy-paving pattern (15%), perilobular pattern (3%), and air trapping (3%). The findings were frequently bilateral (89%), with a random distribution (68%). Pleural effusion, when observed, was typically minimal. No lymphadenopathy was identified. Conclusions: the most common findings were ground-glass opacities and consolidations, or a combination of both. Involvement was commonly bilateral with no axial or cranio caudal predominance in the distribution. Although the major tomographic findings in H1N1 infection are nonspecific, it is important to recognize such findings in order to include infection with the H1N1 virus in the differential diagnosis of respiratory symptoms. (author)

  7. Influenza A(H1N1)pdm09 in critically ill children admitted to a ...

    African Journals Online (AJOL)

    tes. Fig. 1. The prevalence of seasonal and pandemic H1N1 (pH1N1) influenza A at RCWMCH and ... Full approval for the study was obtained from the Human Research ... respiratory virus infection, had not received prophylactic oseltamivir,.

  8. Comparative pathology of pigs infected with Korean H1N1, H1N2, or H3N2 swine influenza A viruses.

    Science.gov (United States)

    Lyoo, Kwang-Soo; Kim, Jeong-Ki; Jung, Kwonil; Kang, Bo-Kyu; Song, Daesub

    2014-09-24

    The predominant subtypes of swine influenza A virus (SIV) in Korea swine population are H1N1, H1N2, and H3N2. The viruses are genetically close to the classical U.S. H1N1 and triple-reassortant H1N2 and H3N2 viruses, respectively. Comparative pathogenesis caused by Korean H1N1, H1N2, and H3N2 SIV was evaluated in this study. The H3N2 infected pigs had severe scores of gross and histopathological lesions at post-inoculation days (PID) 2, and this then progressively decreased. Both the H1N1 and H1N2 infected pigs lacked gross lesions at PID 2, but they showed moderate to severe pneumonia on PID 4, 7 and 14. The pigs infected with H1N1 had significant scores of gross and histopathological lesions when compared with the other pigs infected with H1N2, H3N2, and mock at PID 14. Mean SIV antigen-positive scores were rarely detected for pigs infected with H1N2 and H3N2 from PID 7, whereas a significantly increased amount of viral antigens were found in the bronchioles and alveolar epithelium of the H1N1infected pigs at PID 14. We demonstrated that Korean SIV subtypes had different pulmonary pathologic patterns. The Korean H3N2 rapidly induced acute lung lesions such as broncho-interstitial pneumonia, while the Korean H1N1 showed longer course of infection as compared to other strains.

  9. 64 multidetector CT findings of influenza A (H1N1) virus in patients with hematologic malignancies

    International Nuclear Information System (INIS)

    El-Badrawy, Adel; Zeidan, Amany; Ebrahim, Mohamed A.

    2012-01-01

    Background. The pandemic of swine-origin H1N1 influenza that began in early 2009 has provided evidence that radiology can assist in the early diagnosis of severe cases. Immunocompromised patients are at increased risk for morbidity and mortality. MDCT is superior to radiography in showing the distribution of the disease. Purpose. To review the 64 multidetector CT thoracic findings of novel swine-origin influenza A (H1N1) virus in patients with hematologic malignancies. Material and Methods. This study included 12 patients (3 women, 9 men; mean age, 32.2 years). All patients proved to be infected with influenza A (H1N1) virus. The hematologic malignancies were acute myeloid leukemia (n = 8), chronic lymphocytic leukemia (n = 2), multiple myeloma (n = 1), and myelodysplastic syndrome (n = 1). All the patients underwent CT scanning using a 64 multidetector CT scanner. Chest CT scans were reviewed for ground-glass opacities (GGOs), consolidation, airway thickening/dilatation, nodules, mediastinal lymphadenopathy, and pleural effusion. Results. More than one CT finding was detected in every patient. Pulmonary affection was bilateral, more on the left side. The affections were mainly peribronchial. Airway wall thickening and dilatation were detected in all 12 patients, GGO in 9/12 patients, nodules in 6/12 patients, consolidation in 6/12 patients, hilar lymphadenopathy in 3/12 patients, and pleural effusion in 2/12 patients. Conclusion. Acute myeloid leukemia is the most common hematologic malignancy affected by influenza A (H1N1) virus. The left lung is affected more than the right one. The most common multidetector CT findings are unilateral or bilateral airway thickening and dilatation. Multidetector CT can be used for early and accurate assessment of pulmonary affection with influenza A H1N1 virus infection

  10. 64 multidetector CT findings of influenza A (H1N1) virus in patients with hematologic malignancies

    Energy Technology Data Exchange (ETDEWEB)

    El-Badrawy, Adel [Dept. of Radiology, Mansoura Faculty of Medicine, Mansoura (Egypt)], E-mail: adelelbadrawy@hotmail.com; Zeidan, Amany [Dept. of Thoracic Medicine, Mansoura Faculty of Medicine, Mansoura (Egypt); Ebrahim, Mohamed A. [Dept. of Medical Oncology, Mansoura Faculty of Medicine, Mansoura (Egypt)

    2012-07-15

    Background. The pandemic of swine-origin H1N1 influenza that began in early 2009 has provided evidence that radiology can assist in the early diagnosis of severe cases. Immunocompromised patients are at increased risk for morbidity and mortality. MDCT is superior to radiography in showing the distribution of the disease. Purpose. To review the 64 multidetector CT thoracic findings of novel swine-origin influenza A (H1N1) virus in patients with hematologic malignancies. Material and Methods. This study included 12 patients (3 women, 9 men; mean age, 32.2 years). All patients proved to be infected with influenza A (H1N1) virus. The hematologic malignancies were acute myeloid leukemia (n = 8), chronic lymphocytic leukemia (n = 2), multiple myeloma (n = 1), and myelodysplastic syndrome (n = 1). All the patients underwent CT scanning using a 64 multidetector CT scanner. Chest CT scans were reviewed for ground-glass opacities (GGOs), consolidation, airway thickening/dilatation, nodules, mediastinal lymphadenopathy, and pleural effusion. Results. More than one CT finding was detected in every patient. Pulmonary affection was bilateral, more on the left side. The affections were mainly peribronchial. Airway wall thickening and dilatation were detected in all 12 patients, GGO in 9/12 patients, nodules in 6/12 patients, consolidation in 6/12 patients, hilar lymphadenopathy in 3/12 patients, and pleural effusion in 2/12 patients. Conclusion. Acute myeloid leukemia is the most common hematologic malignancy affected by influenza A (H1N1) virus. The left lung is affected more than the right one. The most common multidetector CT findings are unilateral or bilateral airway thickening and dilatation. Multidetector CT can be used for early and accurate assessment of pulmonary affection with influenza A H1N1 virus infection.

  11. Streptococcus pneumoniae Coinfection Is Correlated with the Severity of H1N1 Pandemic Influenza

    Science.gov (United States)

    Cisterna, Daniel; Savji, Nazir; Bussetti, Ana Valeria; Kapoor, Vishal; Hui, Jeffrey; Tokarz, Rafal; Briese, Thomas; Baumeister, Elsa; Lipkin, W. Ian

    2009-01-01

    Background Initial reports in May 2009 of the novel influenza strain H1N1pdm estimated a case fatality rate (CFR) of 0.6%, similar to that of seasonal influenza. In July 2009, however, Argentina reported 3056 cases with 137 deaths, representing a CFR of 4.5%. Potential explanations for increased CFR included virus reassortment or genetic drift, or infection of a more vulnerable population. Virus genomic sequencing of 26 Argentinian samples representing both severe and mild disease indicated no evidence of reassortment, mutations associated with resistance to antiviral drugs, or genetic drift that might contribute to virulence. Furthermore, no evidence was found for increased frequency of risk factors for H1N1pdm disease. Methods/Principal Findings We examined nasopharyngeal swab samples (NPS) from 199 cases of H1N1pdm infection from Argentina with MassTag PCR, testing for 33 additional microbial agents. The study population consisted of 199 H1N1pdm-infected subjects sampled between 23 June and 4 July 2009. Thirty-nine had severe disease defined as death (n = 20) or hospitalization (n = 19); 160 had mild disease. At least one additional agent of potential pathogenic importance was identified in 152 samples (76%), including Streptococcus pneumoniae (n = 62); Haemophilus influenzae (n = 104); human respiratory syncytial virus A (n = 11) and B (n = 1); human rhinovirus A (n = 1) and B (n = 4); human coronaviruses 229E (n = 1) and OC43 (n = 2); Klebsiella pneumoniae (n = 2); Acinetobacter baumannii (n = 2); Serratia marcescens (n = 1); and Staphylococcus aureus (n = 35) and methicillin-resistant S. aureus (MRSA, n = 6). The presence of S. pneumoniae was strongly correlated with severe disease. S. pneumoniae was present in 56.4% of severe cases versus 25% of mild cases; more than one-third of H1N1pdm NPS with S. pneumoniae were from subjects with severe disease (22 of 62 S. pneumoniae-positive NPS, p = 0

  12. Influenza A/H1N1 Severe Pneumonia: Novel Morphocytological Findings in Bronchoalveolar Lavage

    Directory of Open Access Journals (Sweden)

    Paola Faverio

    2014-01-01

    Full Text Available We present the results of bronchoalveolar lavage (BAL performed in three patients with severe influenza A/H1N1 pneumonia complicated by acute respiratory distress syndrome (ARDS. Light microscopy analysis of BAL cytocentrifugates showed the presence of characteristic large, mononuclear, plasmoblastic/plasmocytoid-like cells never described before. Via transmission electron microscopy, these cells were classified as atypical type II pneumocytes and some of them showed cytoplasmic vesicles and inclusions. We concluded that plasmoblastic/plasmocytoid-like type II pneumocytes might represent a morphologic marker of A/H1N1 influenza virus infection as well as reparative cellular activation after diffuse alveolar damage.

  13. Case of seasonal reassortant A(H1N2) influenza virus infection, the Netherlands, March 2018.

    Science.gov (United States)

    Meijer, Adam; Swaan, Corien M; Voerknecht, Martin; Jusic, Edin; van den Brink, Sharon; Wijsman, Lisa A; Voordouw, Bettie Cg; Donker, Gé A; Sleven, Jacqueline; Dorigo-Zetsma, Wendelien W; Svraka, Sanela; van Boven, Michiel; Haverkate, Manon R; Timen, Aura; van Dissel, Jaap T; Koopmans, Marion Pg; Bestebroer, Theo M; Fouchier, Ron Am

    2018-04-01

    A seasonal reassortant A(H1N2) influenza virus harbouring genome segments from seasonal influenza viruses A(H1N1)pdm09 (HA and NS) and A(H3N2) (PB2, PB1, PA, NP, NA and M) was identified in March 2018 in a 19-months-old patient with influenza-like illness (ILI) who presented to a general practitioner participating in the routine sentinel surveillance of ILI in the Netherlands. The patient recovered fully. Further epidemiological and virological investigation did not reveal additional cases.

  14. Caveolin-1 influences human influenza A virus (H1N1 multiplication in cell culture

    Directory of Open Access Journals (Sweden)

    Hemgård Gun-Viol

    2010-05-01

    Full Text Available Abstract Background The threat of recurring influenza pandemics caused by new viral strains and the occurrence of escape mutants necessitate the search for potent therapeutic targets. The dependence of viruses on cellular factors provides a weak-spot in the viral multiplication strategy and a means to interfere with viral multiplication. Results Using a motif-based search strategy for antiviral targets we identified caveolin-1 (Cav-1 as a putative cellular interaction partner of human influenza A viruses, including the pandemic influenza A virus (H1N1 strains of swine origin circulating from spring 2009 on. The influence of Cav-1 on human influenza A/PR/8/34 (H1N1 virus replication was determined in inhibition and competition experiments. RNAi-mediated Cav-1 knock-down as well as transfection of a dominant-negative Cav-1 mutant results in a decrease in virus titre in infected Madin-Darby canine kidney cells (MDCK, a cell line commonly used in basic influenza research as well as in virus vaccine production. To understand the molecular basis of the phenomenon we focussed on the putative caveolin-1 binding domain (CBD located in the lumenal, juxtamembranal portion of the M2 matrix protein which has been identified in the motif-based search. Pull-down assays and co-immunoprecipitation experiments showed that caveolin-1 binds to M2. The data suggest, that Cav-1 modulates influenza virus A replication presumably based on M2/Cav-1 interaction. Conclusion As Cav-1 is involved in the human influenza A virus life cycle, the multifunctional protein and its interaction with M2 protein of human influenza A viruses represent a promising starting point for the search for antiviral agents.

  15. Preparasi Imunoglobulin G Kelinci sebagai Antigen Penginduksi Antibodi Spesifik Terhadap Virus Avian Influenza H5N1 Strain Legok

    Directory of Open Access Journals (Sweden)

    Ketut Karuni Nyanakumari Natih

    2010-06-01

    Full Text Available The aim of this research was to prepare rabbit Immunoglobulin G as anti-idiotype antibody (Ab2 ofAvian Influenza Virus (AIV H5N1. A polyclonal antibody was collected from guinea pigs immunized withinactivated AI vaccine H5N1of Legok strain. Antibody of H5N1 AI in serum was detected by Agar gelprecipitation test (AGPT and an Inhibition Hemmaglutination test (IHT. The highest titre of antibodywas obtained one week after the third immunization. Serum of guinea pigs containing IgG was purifiedusing the Montage Antibody purification kit & spin column with Prosep A media (Millipore. The AI H5N1IgG concentration was 8 mg/ml. AI H5N1 IgG, was then digested with pepsin to obtain F(ab2 fraction andwas called Ab1. The concentration of IgG and F(ab2 and purity of IgG were determined by UVspectrophotometer which showed Ab1 concentration 1 mg/ml. Molecular weight was estimated by sodiumdodecyl sulfate- polyacrilamide gel electrophoresis (SDS-PAGE. Ab2 was produced by immunization ofrabbit with Ab1. The first immunization was carried out by subcutaneous injection with 500 ?g of Ab1emulsified in Complete Freund Adjuvant. The immunization was repeated with the same dose of Ab1emulsified in Incomplete Freund Adjuvan at 1 week intervals. One week after the second immunization,rabbit’s serum was harvested and IgG was purified using the Montage Antibody purification kit & spincolumn with Prosep A media (Millipore. The rabbit IgG, called Ab2, was an anti-idiotypic antibody againstAIV-H5N1. In AGPT, a precipitation line appeared between Ab1 and Ab2. A partial reaction appearedbetween Ab2 and the AI H5N1 antigen was also detected. The results indicated that Ab2 is a possiblecandidate of imunogen for protection against an AI virus H5N1 infection.

  16. Infection by rhinovirus: similarity of clinical signs included in the case definition of influenza IAn/H1N1.

    Science.gov (United States)

    de Oña Navarro, Maria; Melón García, Santiago; Alvarez-Argüelles, Marta; Fernández-Verdugo, Ana; Boga Riveiro, Jose Antonio

    2012-08-01

    Although new influenza virus (IAn/H1N1) infections are mild and indistinguishable from any other seasonal influenza virus infections, there are few data on comparisons of the clinical features of infection with (IAn/H1N1) and with other respiratory viruses. The incidence, clinical aspects and temporal distribution of those respiratory viruses circulating during flu pandemic period were studied. Respiratory samples from patients with acute influenza-like symptoms were collected from May 2009 to December 2009. Respiratory viruses were detected by conventional culture methods and genome amplification techniques. Although IAn/H1N1 was the virus most frequently detected, several other respiratory viruses co-circulated with IAn/H1N1 during the pandemic period, especially rhinovirus. The similarity between clinical signs included in the clinical case definition for influenza and those caused by other respiratory viruses, particularly rhinovirus, suggest that a high percentage of viral infections were clinically diagnosed as case of influenza. Our study offers useful information to face future pandemics caused by influenza virus, indicating that differential diagnoses are required in order to not overestimate the importance of the pandemic. Copyright © 2011 Elsevier España, S.L. All rights reserved.

  17. Factors Influencing School Closure and Dismissal Decisions: Influenza A (H1N1), Michigan 2009

    Science.gov (United States)

    Dooyema, Carrie A.; Copeland, Daphne; Sinclair, Julie R.; Shi, Jianrong; Wilkins, Melinda; Wells, Eden; Collins, Jim

    2014-01-01

    Background: In fall 2009, many US communities experienced school closures during the influenza A H1N1 pandemic (pH1N1) and the state of Michigan reported 567 closures. We conducted an investigation in Michigan to describe pH1N1-related school policies, practices, and identify factors related to school closures. Methods: We distributed an online…

  18. Characteristics and outcome of critically ill patients with 2009 H1N1 influenza infection in Syria

    Science.gov (United States)

    Alsadat, Reem; Dakak, Abdulrahman; Mazlooms, Mouna; Ghadhban, Ghasan; Fattoom, Shadi; Betelmal, Ibrahim; Abouchala, Nabil; Kherallah, Mazen

    2012-01-01

    Objectives: To describe the epidemiologic characteristics, clinical features, and outcome of severe cases of 2009 H1N1 influenza A infections who were admitted to the intensive care units (ICUs) in Damascus, Syria. Materials and Methods: Retrospectively, we collected clinical data on all patients who were admitted to the ICU with confirmed or suspected diagnosis of severe 2009 H1N1 influenza A with respiratory failure at 4 major tertiary care hospitals in Damascus, Syria. Acute Physiology and Chronic Health Evaluation (APACHE) II system was used to assess the severity of illness within the first 24 h after admission. The outcome was overall hospital mortality. Results: Eighty patients were admitted to the ICU with severe 2009 H1N1 infection. The mean age was 40.7 years; 69.8% of patients had ≥1 of the risk factors: asthmatics 20%, obesity 23.8%, and pregnancy 5%; and 72.5% had acute lung injury or adult respiratory distress syndrome, 12.5% had viral pneumonia, 42.5% had secondary bacterial pneumonia, and 15% had exacerbation of airflow disease. Mechanical ventilation was required in 73.7% of cases. The mean hospital length of stay was 11.7 days (median 8 days, range 0–77 days, IQR: 5–14 days). The overall mortality rate was 51% for a mean APACHE II score of 15.2 with a predicted mortality of 21% (standardized mortality ratio of 2.4, 95% confidence interval: 1.7–3.2, P value < 0.001). Conclusion: Critically ill patients with severe 2009 H1N1 infection in this limited resource country had a much higher mortality rate than the predicted APACHE II mortality rate or when compared with the reported mortality rates for severe cases in other countries during 2009 H1N1 pandemic. PMID:23210019

  19. Novel Highly Pathogenic Avian Influenza A(H5N6) Virus in the Netherlands, December 2017.

    Science.gov (United States)

    Beerens, Nancy; Koch, Guus; Heutink, Rene; Harders, Frank; Vries, D P Edwin; Ho, Cynthia; Bossers, Alex; Elbers, Armin

    2018-04-17

    A novel highly pathogenic avian influenza A(H5N6) virus affecting wild birds and commercial poultry was detected in the Netherlands in December 2017. Phylogenetic analysis demonstrated that the virus is a reassortant of H5N8 clade 2.3.4.4 viruses and not related to the Asian H5N6 viruses that caused human infections.

  20. Influenza A(H9N2) Virus, Myanmar, 2014-2015.

    Science.gov (United States)

    Lin, Thant Nyi; Nonthabenjawan, Nutthawan; Chaiyawong, Supassama; Bunpapong, Napawan; Boonyapisitsopa, Supanat; Janetanakit, Taveesak; Mon, Pont Pont; Mon, Hla Hla; Oo, Kyaw Naing; Oo, Sandi Myint; Mar Win, Mar; Amonsin, Alongkorn

    2017-06-01

    Routine surveillance of influenza A virus was conducted in Myanmar during 2014-2015. Influenza A(H9N2) virus was isolated in Shan State, upper Myanmar. Whole-genome sequencing showed that H9N2 virus from Myanmar was closely related to H9N2 virus of clade 4.2.5 from China.

  1. Los virus Influenza y la nueva pandemia A/H1N1

    Directory of Open Access Journals (Sweden)

    Miguel Talledo

    2011-07-01

    Full Text Available Los virus Influenza pertenecen a la familia Orthomyxoviridae, virus con genoma RNA de sentido negativo segmentado. Los virus influenza tipo A infectan a humanos y otros organismos, y son los agentes causantes de influenza en humanos. Resaltan entre sus principales proteínas la Hemaglutinina y la Neuraminidasa, que son utilizadas en la clasificación de los miembros de este grupo. Estos virus mutan continuamente, exhibiendo patrones muy estudiados, como el cambio y la deriva antigénica, siendo uno de los principales eventos de recombinación el reordenamiento. Todos los subtipos se encuentran en aves acuáticas silvestres, aunque se han encontrado otros hospederos, como equinos, visones, ballenas, focas, cerdos, gallinas y pavos, entre otros. Tanto las aves salvajes, las aves domésticas y el cerdo juegan un rol fundamental en la adaptación progresiva del virus al hospedero humano. Aunque los subtipos H2N2 y H3N2 han sido muy comunes, el subtipo H1N1 ha reemergido con mutaciones que le han permitido alcanzar el estado de pandemia en 2009. Este nuevo virus surge de un virus generado por triple reordenamiento con el virus humano, porcino norteamericano y aviar, conteniendo a su vez segmentos génicos de virus influenza porcina euroasiática. Esto ha hecho que el virus presente una enfermedad humana moderada y solamente severa y hasta letal en casos de individuos con condiciones médicas previas. A nivel mundial ha causado más de 134,510 casos y en el Perú alcanza cerca de 3,700 casos. El estado actual indica que la pandemia está por llegar a su pico máximo en el Perú, debido a la alta morbilidad del virus coincidente con la estación más fría del año. Es importante contener al máximo la dispersión del virus, ya que cuanto mayor sea el número de personas que infecte, el mismo estará sometido a un mayor número de eventos de recombinación genética por reordenamiento con virus influenza humanos previos y esto puede condicionar a la

  2. Identification of Human H1N2 and Human-Swine Reassortant H1N2 and H1N1 Influenza A Viruses among Pigs in Ontario, Canada (2003 to 2005)†

    OpenAIRE

    Karasin, Alexander I.; Carman, Suzanne; Olsen, Christopher W.

    2006-01-01

    Since 2003, three novel genotypes of H1 influenza viruses have been recovered from Canadian pigs, including a wholly human H1N2 virus and human-swine reassortants. These isolates demonstrate that human-lineage H1N2 viruses are infectious for pigs and that viruses with a human PB1/swine PA/swine PB2 polymerase complex can replicate in pigs.

  3. Efficacy of a pandemic (H1N1) 2009 virus vaccine in pigs against the pandemic influenza virus is superior to commercially available swine influenza vaccines.

    NARCIS (Netherlands)

    Loeffen, W.L.A.; Stockhofe-Zurwieden, N.; Weesendorp, E.; Zoelen-Bos, van D.J.; Heutink, R.; Quak, J.; Goovaerts, D.; Heldens, J.; Maas, H.A.; Moormann, R.J.M.; Koch, G.

    2011-01-01

    In April 2009 a new influenza A/H1N1 strain, currently named “pandemic (H1N1) influenza 2009¿ (H1N1v), started the first official pandemic in humans since 1968. Several incursions of this virus in pig herds have also been reported from all over the world. Vaccination of pigs may be an option to

  4. H1N1 influenza viruses varying widely in hemagglutinin stability transmit efficiently from swine to swine and to ferrets.

    Directory of Open Access Journals (Sweden)

    Marion Russier

    2017-03-01

    Full Text Available A pandemic-capable influenza virus requires a hemagglutinin (HA surface glycoprotein that is immunologically unseen by most people and is capable of supporting replication and transmission in humans. HA stabilization has been linked to 2009 pH1N1 pandemic potential in humans and H5N1 airborne transmissibility in the ferret model. Swine have served as an intermediate host for zoonotic influenza viruses, yet the evolutionary pressure exerted by this host on HA stability was unknown. For over 70 contemporary swine H1 and H3 isolates, we measured HA activation pH to range from pH 5.1 to 5.9 for H1 viruses and pH 5.3 to 5.8 for H3 viruses. Thus, contemporary swine isolates vary widely in HA stability, having values favored by both avian (pH >5.5 and human and ferret (pH5.5 species. Using an early 2009 pandemic H1N1 (pH1N1 virus backbone, we generated three viruses differing by one HA residue that only altered HA stability: WT (pH 5.5, HA1-Y17H (pH 6.0, and HA2-R106K (pH 5.3. All three replicated in pigs and transmitted from pig-to-pig and pig-to-ferret. WT and R106 viruses maintained HA genotype and phenotype after transmission. Y17H (pH 6.0 acquired HA mutations that stabilized the HA protein to pH 5.8 after transmission to pigs and 5.5 after transmission to ferrets. Overall, we found swine support a broad range of HA activation pH for contact transmission and many recent swine H1N1 and H3N2 isolates have stabilized (human-like HA proteins. This constitutes a heightened pandemic risk and underscores the importance of ongoing surveillance and control efforts for swine viruses.

  5. Influenza A (H1N1) was not associated with obesity in pregnant women living in Toluca, México.

    Science.gov (United States)

    Mendieta-Zerón, Hugo; Santillán-Benítez, Jonnathan G; Colín-Ferreira, María del Carmen; Montenegro-Cárdenas, Angela; Núñez-Delira, Cynthia N; Huitrón-Bravo, Gabriel G

    2011-12-01

    The aim was to verify whether being overweight could have played a critical role in cases of mortality caused by influenza A (H1N1) in pregnant women. This virus' prevalence was also analyzed among people suffering from acute respiratory disease being attended at the state of Mexico's Autonomous University's medical research centre. The clinical files of women having influenza A (H1N1) attending the Monica Pretelini maternal-perinatal hospital's (HMPMP) intensive care unit in Toluca, Mexico, were reviewed. According to international recommendations, clinical detection of possible new cases of this disease was kept an open as a second step. Five women suffering influenza A (H1N1) was attended at HMPMP's intensive care unit during 2009; only one survived. No differences in body mass index were found when comparing the anthropometric characteristics to another group of women affected by acute respiratory diseases; in fact, this parameter was below the limits for being overweight in both cases. No new case of influenza A (H1N1) was found after the first eight months of 2010. It could not be verified whether being overweight was a factor of higher mortality due to influenza A (H1N1) amongst pregnant women in the state of Mexico. The key to better survival for pregnant women hospitalized with influenza A (H1N1) seemed to be early treatment with oseltamivir. The cases decreased dramatically after the severe wave of the new pandemic due to unknown reasons.

  6. Full genomic analysis of an influenza A (H1N2) virus identified during 2009 pandemic in Eastern India: evidence of reassortment event between co-circulating A(H1N1)pdm09 and A/Brisbane/10/2007-like H3N2 strains.

    Science.gov (United States)

    Mukherjee, Tapasi Roy; Agrawal, Anurodh S; Chakrabarti, Sekhar; Chawla-Sarkar, Mamta

    2012-10-11

    During the pandemic [Influenza A(H1N1)pdm09] period in 2009-2010, an influenza A (Inf-A) virus with H1N2 subtype (designated as A/Eastern India/N-1289/2009) was detected from a 25 years old male from Mizoram (North-eastern India). To characterize full genome of the H1N2 influenza virus. For initial detection of Influenza viruses, amplification of matrix protein (M) gene of Inf-A and B viruses was carried out by real time RT-PCR. Influenza A positive viruses are then further subtyped with HA and NA gene specific primers. Sequencing and the phylogenetic analysis was performed for the H1N2 strain to understand its origin. The outcome of this full genome study revealed a unique reassortment event where the N-1289 virus acquired it's HA gene from a 2009 pandemic H1N1 virus with swine origin and the other genes from H3N2-like viruses of human origin. This study provides information on possibility of occurrence of reassortment events during influenza season when infectivity is high and two different subtypes of Inf-A viruses co-circulate in same geographical location.

  7. A Novel Duplex Real-Time Reverse-Transcription PCR Assay for the Detection of Influenza A and the Novel Influenza A(H1N1 Strain

    Directory of Open Access Journals (Sweden)

    Theo P. Sloots

    2009-12-01

    Full Text Available Timely implementation of antiviral treatment and other public health based responses are dependent on accurate and rapid diagnosis of the novel pandemic influenza A(H1N1 strain. In this study we developed a duplex real-time PCR (RT-PCR (dFLU-TM assay for the simultaneous detection of a broad range of influenza A subtypes and specific detection of the novel H1N1 2009 pandemic strain. The assay was compared to the combined results of two previously described monoplex RT-PCR assays using 183 clinical samples and 10 seasonal influenza A isolates. Overall, the results showed that the dFLU-TM RT-PCR method is suitable for detection of influenza A, including the novel H1N1 pandemic strain, in clinical samples.

  8. Experimental infection of macaques with a wild water bird-derived highly pathogenic avian influenza virus (H5N1.

    Directory of Open Access Journals (Sweden)

    Tomoko Fujiyuki

    Full Text Available Highly pathogenic avian influenza virus (HPAIV continues to threaten human health. Non-human primate infection models of human influenza are desired. To establish an animal infection model with more natural transmission and to determine the pathogenicity of HPAIV isolated from a wild water bird in primates, we administered a Japanese isolate of HPAIV (A/whooper swan/Hokkaido/1/2008, H5N1 clade 2.3.2.1 to rhesus and cynomolgus monkeys, in droplet form, via the intratracheal route. Infection of the lower and upper respiratory tracts and viral shedding were observed in both macaques. Inoculation of rhesus monkeys with higher doses of the isolate resulted in stronger clinical symptoms of influenza. Our results demonstrate that HPAIV isolated from a water bird in Japan is pathogenic in monkeys by experimental inoculation, and provide a new method for HPAIV infection of non-human primate hosts, a good animal model for investigation of HPAIV pathogenicity.

  9. Surveillance plan for the early detection of H5N1 highly pathogenic avian influenza virus in migratory birds in the United States: surveillance year 2009

    Science.gov (United States)

    Brand, Christopher J.

    2009-01-01

    Executive Summary: This Surveillance Plan (Plan) describes plans for conducting surveillance of wild birds in the United States and its Territories and Freely-Associated States to provide for early detection of the introduction of the H5N1 Highly Pathogenic Avian Influenza (HPAI) subtype of the influenza A virus by migratory birds during the 2009 surveillance year, spanning the period of April 1, 2009 - March 31, 2010. The Plan represents a continuation of surveillance efforts begun in 2006 under the Interagency Strategic Plan for the Early Detection of H5N1 Highly Pathogenic Avian Influenza in Wild Migratory Birds (U.S. Department of Agriculture and U.S. Department of the Interior, 2006). The Plan sets forth sampling plans by: region, target species or species groups to be sampled, locations of sampling, sample sizes, and sampling approaches and methods. This Plan will be reviewed annually and modified as appropriate for subsequent surveillance years based on evaluation of information from previous years of surveillance, changing patterns and threats of H5N1 HPAI, and changes in funding availability for avian influenza surveillance. Specific sampling strategies will be developed accordingly within each of six regions, defined here as Alaska, Hawaiian/Pacific Islands, Lower Pacific Flyway (Washington, Oregon, California, Idaho, Nevada, Arizona), Central Flyway, Mississippi Flyway, and Atlantic Flyway.

  10. Positive Selection on Hemagglutinin and Neuraminidase Genes of H1N1 Influenza Viruses

    LENUS (Irish Health Repository)

    Li, Wenfu

    2011-04-21

    Abstract Background Since its emergence in March 2009, the pandemic 2009 H1N1 influenza A virus has posed a serious threat to public health. To trace the evolutionary path of these new pathogens, we performed a selection-pressure analysis of a large number of hemagglutinin (HA) and neuraminidase (NA) gene sequences of H1N1 influenza viruses from different hosts. Results Phylogenetic analysis revealed that both HA and NA genes have evolved into five distinct clusters, with further analyses indicating that the pandemic 2009 strains have experienced the strongest positive selection. We also found evidence of strong selection acting on the seasonal human H1N1 isolates. However, swine viruses from North America and Eurasia were under weak positive selection, while there was no significant evidence of positive selection acting on the avian isolates. A site-by-site analysis revealed that the positively selected sites were located in both of the cleaved products of HA (HA1 and HA2), as well as NA. In addition, the pandemic 2009 strains were subject to differential selection pressures compared to seasonal human, North American swine and Eurasian swine H1N1 viruses. Conclusions Most of these positively and\\/or differentially selected sites were situated in the B-cell and\\/or T-cell antigenic regions, suggesting that selection at these sites might be responsible for the antigenic variation of the viruses. Moreover, some sites were also associated with glycosylation and receptor-binding ability. Thus, selection at these positions might have helped the pandemic 2009 H1N1 viruses to adapt to the new hosts after they were introduced from pigs to humans. Positive selection on position 274 of NA protein, associated with drug resistance, might account for the prevalence of drug-resistant variants of seasonal human H1N1 influenza viruses, but there was no evidence that positive selection was responsible for the spread of the drug resistance of the pandemic H1N1 strains.

  11. Detection of H5N1 high-pathogenicity avian influenza virus in meat and tracheal samples from experimentally infected chickens.

    Science.gov (United States)

    Das, Amaresh; Spackman, Erica; Thomas, Colleen; Swayne, David E; Suarez, David L

    2008-03-01

    The Asian H5N1 highly pathogenic avian influenza (HPAI) virus causes a systemic disease with high mortality of poultry and is potentially zoonotic. In both chickens and ducks, the virus has been demonstrated to replicate in both cardiac and skeletal muscle cells. Experimentally, H5N1 HPAI virus has been transmitted to chickens through the consumption of raw infected meat. In this study, we investigated virus replication in cardiac and skeletal muscle and in the trachea of chickens after experimental intranasal inoculation with the H5N1 HPAI virus. The virus was detected in tissues by real-time reverse transcription-polymerase chain reaction (RRT-PCR) and virus isolation, and in the trachea by RRT-PCR and a commercial avian influenza (AI) viral antigen detection test. A modified RNA extraction protocol was developed for rapid detection of the virus in tissues by RRT-PCR. The H5N1 HPAI virus was sporadically detected in meat and the tracheas of infected birds without any clinical sign of disease as early as 6 hr postinfection (PI), and was detected in all samples tested at 24 hr PI and later. No differences in sensitivity were seen between virus isolation and RRT-PCR in meat samples. The AI viral antigen detection test on tracheal swabs was a useful method for identifying infected chickens when they were sick or dead, but was less sensitive in detecting infected birds when they were preclinical. This study provides data indicating that preslaughter tracheal swab testing can identify birds infected with HPAI among the daily mortality and prevent infected flocks from being sent to processing plants. In addition, the modified RNA extraction and RRT-PCR test on meat samples provide a rapid and sensitive method of identifying HPAI virus in illegal contraband or domestic meat samples.

  12. Pandemic H1N1 2009 virus in Norwegian pigs naïve to influenza A viruses

    DEFF Research Database (Denmark)

    Germundsson, A.; Gjerset, B.; Hjulsager, Charlotte Kristiane

    In March-April 2009, a novel pandemic influenza A (H1N1) virus (pH1N1-09v) emerged in the human population. The first case of pH1N1v infection in pigs was reported from Canada in May 2009. In Norway, pH1N1v infection was recorded in a swine herd on the 10th of October of 2009. Here, we report...... isolated from a confirmed human case at the farm. The majority of the positive herds had a history of contact with humans that were diagnosed with pandemic influenza or with ILI. This suggests that infected humans are the most likely source for introduction of pH1N1-09v to the Norwegian pig herds...

  13. Enhanced surveillance of initial cases of pandemic H1N1 2009 influenza in Ireland, April-July 2009.

    LENUS (Irish Health Repository)

    Martin, J

    2009-09-24

    From 28 April to 18 July 2009 there were 156 cases of pandemic H1N1 2009 influenza confirmed in Ireland. During this time, Ireland was in containment phase, and detailed case-based epidemiological information was gathered on all cases presenting in the community and acute health care setting. Active case finding was performed among contacts of cases. Eighty percent of cases were in people less than 35 years of age and 86% were imported. The most frequent symptoms were fever, sore throat, myalgia and dry cough. Nine people were hospitalized, no fatalities occurred.

  14. Safety and immunogenicity of adjuvanted inactivated split-virion and whole-virion influenza A (H5N1) vaccines in children: a phase I-II randomized trial.

    Science.gov (United States)

    Wu, Jiang; Liu, Shu-Zhen; Dong, Shan-Shan; Dong, Xiao-Ping; Zhang, Wu-Li; Lu, Min; Li, Chang-Gui; Zhou, Ji-Chen; Fang, Han-Hua; Liu, Yan; Liu, Li-Ying; Qiu, Yuan-Zheng; Gao, Qiang; Zhang, Xiao-Mei; Chen, Jiang-Ting; Zhong, Xiang; Yin, Wei-Dong; Feng, Zi-Jian

    2010-08-31

    Highly pathogenic avian influenza A virus H5N1 has the potential to cause a pandemic. Many prototype pandemic influenza A (H5N1) vaccines had been developed and well evaluated in adults in recent years. However, data in children are limited. Herein we evaluate the safety and immunogenicity of adjuvanted split-virion and whole-virion H5N1 vaccines in children. An open-labelled phase I trial was conducted in children aged 3-11 years to receive aluminum-adjuvated, split-virion H5N1 vaccine (5-30 microg) and in children aged 12-17 years to receive aluminum-adjuvated, whole-virion H5N1 vaccine (5-15 microg). Safety of the two formulations was assessed. Then a randomized phase II trial was conducted, in which 141 children aged 3-11 years received the split-virion vaccine (10 or 15 microg) and 280 children aged 12-17 years received the split-virion vaccine (10-30 microg) or the whole-virion vaccine (5 microg). Serum samples were collected for hemagglutination-inhibition (HI) assays. 5-15 microg adjuvated split-virion vaccines were well tolerated in children aged 3-11 years and 5-30 microg adjuvated split-virion vaccines and 5 microg adjuvated whole-virion vaccine were well tolerated in children aged 12-17 years. Most local and systemic reactions were mild or moderate. Before vaccination, all participants were immunologically naïve to H5N1 virus. Immune responses were induced after the first dose and significantly boosted after the second dose. In 3-11 years children, the 10 and 15 microg split-virion vaccine induced similar responses with 55% seroconversion and seroprotection (HI titer >or=1:40) rates. In 12-17 years children, the 30 microg split-virion vaccine induced the highest immune response with 71% seroconversion and seroprotection rates. The 5 microg whole-virion vaccine induced higher response than the 10 microg split-virion vaccine did. The aluminum-adjuvanted, split-virion prototype pandemic influenza A (H5N1) vaccine showed good safety and immunogenicity in

  15. The effect of age on the pathogenesis of a highly pathogenic avian influenza (HPAI) H5N1 virus in Pekin ducks (Anas platyrhynchos) infected experimentally

    OpenAIRE

    L?ndt, Brandon Z.; N??ez, Alejandro.; Banks, Jill; Alexander, Dennis J.; Russell, Christine; Richard? L?ndt, Angela C.; Brown, Ian H.

    2009-01-01

    Background? Highly pathogenic avian influenza (HPAI) H5N1 viruses have recently displayed increased virulence for wild waterfowl. Objectives? To study the effect of host age on the shedding and tissue dissemination of a HPAI H5N1 virus in infected Pekin ducks. Methods? Pekin ducks in two age?matched groups (n?=?18), 8 and 12?weeks old (wo) were each infected with 106 EID50/0?1?ml of HPAI A/turkey/Turkey/1/05 (H5N1, clade 2?2). Each day for 5?days, birds were monitored clinically, and cloacal ...

  16. Risk factors for exposure to influenza a viruses, including subtype H5 viruses, in Thai free-grazing ducks.

    Science.gov (United States)

    Beaudoin, A L; Kitikoon, P; Schreiner, P J; Singer, R S; Sasipreeyajan, J; Amonsin, A; Gramer, M R; Pakinsee, S; Bender, J B

    2014-08-01

    Free-grazing ducks (FGD) have been associated with highly pathogenic avian influenza (HPAI) H5N1 outbreaks and may be a viral reservoir. In July-August 2010, we assessed influenza exposure of Thai FGD and risk factors thereof. Serum from 6254 ducks was analysed with enzyme-linked immunosorbent assay (ELISA) to detect antibodies to influenza A nucleoprotein (NP), and haemagglutinin H5 protein. Eighty-five per cent (5305 ducks) were seropositive for influenza A. Of the NP-seropositive sera tested with H5 assays (n = 1423), 553 (39%) were H5 ELISA positive and 57 (4%) suspect. Twelve per cent (74 of 610) of H5 ELISA-positive/suspect ducks had H5 titres ≥ 1 : 20 by haemagglutination inhibition. Risk factors for influenza A seropositivity include older age, poultry contact, flock visitors and older purchase age. Study flocks had H5 virus exposure as recently as March 2010, but no HPAI H5N1 outbreaks have been identified in Thailand since 2008, highlighting a need for rigorous FGD surveillance. © 2012 Blackwell Verlag GmbH.

  17. Temperature sensitivity on growth and/or replication of H1N1, H1N2 and H3N2 influenza A viruses isolated from pigs and birds in mammalian cells.

    Science.gov (United States)

    Massin, Pascale; Kuntz-Simon, Gaëlle; Barbezange, Cyril; Deblanc, Céline; Oger, Aurélie; Marquet-Blouin, Estelle; Bougeard, Stéphanie; van der Werf, Sylvie; Jestin, Véronique

    2010-05-19

    Influenza A viruses have been isolated from a wide range of animal species, aquatic birds being the reservoir for their genetic diversity. Avian influenza viruses can be transmitted to humans, directly or indirectly through an intermediate host like pig. This study aimed to define in vitro conditions that could prove useful to evaluate the potential of influenza viruses to adapt to a different host. Growth of H1N1, H1N2 and H3N2 influenza viruses belonging to different lineages isolated from birds or pigs prior to 2005 was tested on MDCK or NPTr cell lines in the presence or absence of exogenous trypsin. Virus multiplication was compared at 33, 37 and 40 degrees C, the infection site temperatures in human, swine and avian hosts, respectively. Temperature sensitivity of PB2-, NP- and M-RNA replication was also tested by quantitative real-time PCR. Multiplication of avian viruses was cold-sensitive, whatever cell type. By contrast, temperature sensitivity of swine viruses was found to depend on the virus and the host cell: for an H1N1 swine isolate from 1982, multiplication was cold-sensitive on NPTr cells and undetectable at 40 degrees C. From genetic analyses, it appears that temperature sensitivity could involve other residues than PB2 residue 627 and could affect other steps of the replication cycle than replication. Copyright 2009 Elsevier B.V. All rights reserved.

  18. International collaboration to assess the risk of Guillain Barre Syndrome following Influenza A (H1N1) 2009 monovalent vaccines

    NARCIS (Netherlands)

    Dodd, Caitlin N.; Romio, Silvana A.; Black, Steven; Vellozzi, Claudia; Andrews, Nick; Sturkenboom, Miriam; Zuber, Patrick; Hua, Wei; Bonhoeffer, Jan; Buttery, Jim; Crawford, Nigel; Deceuninck, Genevieve; de Vries, Corinne; De Wals, Philippe; Gutierrez-Gimeno, M. Victoria; Heijbel, Harald; Hughes, Hayley; Hur, Kwan; Hviid, Anders; Kelman, Jeffrey; Kilpi, Tehri; Chuang, S. K.; Macartney, Kristine; Rett, Melisa; Lopez-Callada, Vesta Richardson; Salmon, Daniel; Sanchez, Francisco Gimenez; Sanz, Nuria; Silverman, Barbara; Storsaeter, Jann; Thirugnanam, Umapathi; van der Maas, Nicoline; Yih, Katherine; Zhang, Tao; Izurieta, Hector

    2013-01-01

    Background: The global spread of the 2009 novel pandemic influenza A (H1N1) virus led to the accelerated production and distribution of monovalent 2009 Influenza A (H1N1) vaccines (pH1N1). This pandemic provided the opportunity to evaluate the risk of Guillain-Barre syndrome (GBS), which has been an

  19. Migration of whooper swans and outbreaks of highly pathogenic avian influenza H5N1 virus in eastern Asia.

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    Scott H Newman

    Full Text Available Evaluating the potential involvement of wild avifauna in the emergence of highly pathogenic avian influenza H5N1 (hereafter H5N1 requires detailed analyses of temporal and spatial relationships between wild bird movements and disease emergence. The death of wild swans (Cygnus spp. has been the first indicator of the presence of H5N1 in various Asian and European countries; however their role in the geographic spread of the disease remains poorly understood. We marked 10 whooper swans (Cygnus cygnus with GPS transmitters in northeastern Mongolia during autumn 2006 and tracked their migratory movements in relation to H5N1 outbreaks. The prevalence of H5N1 outbreaks among poultry in eastern Asia during 2003-2007 peaked during winter, concurrent with whooper swan movements into regions of high poultry density. However outbreaks involving poultry were detected year round, indicating disease perpetuation independent of migratory waterbird presence. In contrast, H5N1 outbreaks involving whooper swans, as well as other migratory waterbirds that succumbed to the disease in eastern Asia, tended to occur during seasons (late spring and summer and in habitats (areas of natural vegetation where their potential for contact with poultry is very low to nonexistent. Given what is known about the susceptibility of swans to H5N1, and on the basis of the chronology and rates of whooper swan migration movements, we conclude that although there is broad spatial overlap between whooper swan distributions and H5N1 outbreak locations in eastern Asia, the likelihood of direct transmission between these groups is extremely low. Thus, our data support the hypothesis that swans are best viewed as sentinel species, and moreover, that in eastern Asia, it is most likely that their infections occurred through contact with asymptomatic migratory hosts (e.g., wild ducks at or near their breeding grounds.

  20. Genetic makeup of amantadine-resistant and oseltamivir-resistant human influenza A/H1N1 viruses.

    Science.gov (United States)

    Zaraket, Hassan; Saito, Reiko; Suzuki, Yasushi; Baranovich, Tatiana; Dapat, Clyde; Caperig-Dapat, Isolde; Suzuki, Hiroshi

    2010-04-01

    The emergence and widespread occurrence of antiviral drug-resistant seasonal human influenza A viruses, especially oseltamivir-resistant A/H1N1 virus, are major concerns. To understand the genetic background of antiviral drug-resistant A/H1N1 viruses, we performed full genome sequencing of prepandemic A/H1N1 strains. Seasonal influenza A/H1N1 viruses, including antiviral-susceptible viruses, amantadine-resistant viruses, and oseltamivir-resistant viruses, obtained from several areas in Japan during the 2007-2008 and 2008-2009 influenza seasons were analyzed. Sequencing of the full genomes of these viruses was performed, and the phylogenetic relationships among the sequences of each individual genome segment were inferred. Reference genome sequences from the Influenza Virus Resource database were included to determine the closest ancestor for each segment. Phylogenetic analysis revealed that the oseltamivir-resistant strain evolved from a reassortant oseltamivir-susceptible strain (clade 2B) which circulated in the 2007-2008 season by acquiring the H275Y resistance-conferring mutation in the NA gene. The oseltamivir-resistant lineage (corresponding to the Northern European resistant lineage) represented 100% of the H1N1 isolates from the 2008-2009 season and further acquired at least one mutation in each of the polymerase basic protein 2 (PB2), polymerase basic protein 1 (PB1), hemagglutinin (HA), and neuraminidase (NA) genes. Therefore, a reassortment event involving two distinct oseltamivir-susceptible lineages, followed by the H275Y substitution in the NA gene and other mutations elsewhere in the genome, contributed to the emergence of the oseltamivir-resistant lineage. In contrast, amantadine-resistant viruses from the 2007-2008 season distinctly clustered in clade 2C and were characterized by extensive amino acid substitutions across their genomes, suggesting that a fitness gap among its genetic components might have driven these mutations to maintain it in the

  1. A Novel H1N2 Influenza Virus Related to the Classical and Human Influenza Viruses from Pigs in Southern China.

    Science.gov (United States)

    Song, Yafen; Wu, Xiaowei; Wang, Nianchen; Ouyang, Guowen; Qu, Nannan; Cui, Jin; Qi, Yan; Liao, Ming; Jiao, Peirong

    2016-01-01

    Southern China has long been considered to be an epicenter of pandemic influenza viruses. The special environment, breeding mode, and lifestyle in southern China provides more chances for wild aquatic birds, domestic poultry, pigs, and humans to be in contact. This creates the opportunity for interspecies transmission and generation of new influenza viruses. In this study, we reported a novel reassortant H1N2 influenza virus from pigs in southern China. According to the phylogenetic trees and homology of the nucleotide sequence, the virus was confirmed to be a novel triple-reassortant H1N2 virus containing genes from classical swine (PB2, PB1, HA, NP, and NS genes), triple-reassortant swine (PA and M genes), and recent human (NA gene) lineages. It indicated that the novel reassortment virus among human and swine influenza viruses occurred in pigs in southern China. The isolation of the novel reassortant H1N2 influenza viruses provides further evidence that pigs are "mixing vessels," and swine influenza virus surveillance in southern China will provide important information about genetic evaluation and antigenic variation of swine influenza virus to formulate the prevention and control measures for the viruses.

  2. Computational Identification of Antigenicity-Associated Sites in the Hemagglutinin Protein of A/H1N1 Seasonal Influenza Virus.

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    Xiaowei Ren

    Full Text Available The antigenic variability of influenza viruses has always made influenza vaccine development challenging. The punctuated nature of antigenic drift of influenza virus suggests that a relatively small number of genetic changes or combinations of genetic changes may drive changes in antigenic phenotype. The present study aimed to identify antigenicity-associated sites in the hemagglutinin protein of A/H1N1 seasonal influenza virus using computational approaches. Random Forest Regression (RFR and Support Vector Regression based on Recursive Feature Elimination (SVR-RFE were applied to H1N1 seasonal influenza viruses and used to analyze the associations between amino acid changes in the HA1 polypeptide and antigenic variation based on hemagglutination-inhibition (HI assay data. Twenty-three and twenty antigenicity-associated sites were identified by RFR and SVR-RFE, respectively, by considering the joint effects of amino acid residues on antigenic drift. Our proposed approaches were further validated with the H3N2 dataset. The prediction models developed in this study can quantitatively predict antigenic differences with high prediction accuracy based only on HA1 sequences. Application of the study results can increase understanding of H1N1 seasonal influenza virus antigenic evolution and accelerate the selection of vaccine strains.

  3. Mortality burden of the 2009 A/H1N1 influenza pandemic in France: comparison to seasonal influenza and the A/H3N2 pandemic.

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    Magali Lemaitre

    Full Text Available BACKGROUND: The mortality burden of the 2009 A/H1N1 pandemic remains unclear in many countries due to delays in reporting of death statistics. We estimate the age- and cause-specific excess mortality impact of the pandemic in France, relative to that of other countries and past epidemic and pandemic seasons. METHODS: We applied Serfling and Poisson excess mortality approaches to model weekly age- and cause-specific mortality rates from June 1969 through May 2010 in France. Indicators of influenza activity, time trends, and seasonal terms were included in the models. We also reviewed the literature for country-specific estimates of 2009 pandemic excess mortality rates to characterize geographical differences in the burden of this pandemic. RESULTS: The 2009 A/H1N1 pandemic was associated with 1.0 (95% Confidence Intervals (CI 0.2-1.9 excess respiratory deaths per 100,000 population in France, compared to rates per 100,000 of 44 (95% CI 43-45 for the A/H3N2 pandemic and 2.9 (95% CI 2.3-3.7 for average inter-pandemic seasons. The 2009 A/H1N1 pandemic had a 10.6-fold higher impact than inter-pandemic seasons in people aged 5-24 years and 3.8-fold lower impact among people over 65 years. CONCLUSIONS: The 2009 pandemic in France had low mortality impact in most age groups, relative to past influenza seasons, except in school-age children and young adults. The historical A/H3N2 pandemic was associated with much larger mortality impact than the 2009 pandemic, across all age groups and outcomes. Our 2009 pandemic excess mortality estimates for France fall within the range of previous estimates for high-income regions. Based on the analysis of several mortality outcomes and comparison with laboratory-confirmed 2009/H1N1 deaths, we conclude that cardio-respiratory and all-cause mortality lack precision to accurately measure the impact of this pandemic in high-income settings and that use of more specific mortality outcomes is important to obtain reliable

  4. Novel H5N8 clade 2.3.4.4 highly pathogenic avian influenza virus in wild awuatic birds, Russia, 2016

    Science.gov (United States)

    H5N1 high pathogenicity avian influenza virus (HPAIV) emerged in 1996 in Guangdong China (Gs/GD) and has evolved into multiple genetic clades. Since 2008, HPAIV H5 clade 2.3.4 with N2, N5 and N8 neuraminidase subtypes have been identified in mainland China and outbreak of HPAIV H5N8 clade 2.3.4.4 ou...

  5. Exposure to a low pathogenic A/H7N2 virus in chickens protects against highly pathogenic A/H7N1 virus but not against subsequent infection with A/H5N1.

    Directory of Open Access Journals (Sweden)

    Júlia Vergara-Alert

    Full Text Available Recent evidences have demonstrated that the presence of low pathogenic avian influenza viruses (LPAIV may play an important role in host ecology and transmission of avian influenza viruses (AIV. While some authors have clearly demonstrated that LPAIV can mutate to render highly pathogenic avian influenza viruses (HPAIV, others have shown that their presence could provide the host with enough immunological memory to resist re-infections with HPAIV. In order to experimentally study the role of pre-existing host immunity, chickens previously infected with H7N2 LPAIV were subsequently challenged with H7N1 HPAIV. Pre-infection of chickens with H7N2 LAPIV conferred protection against the lethal challenge with H7N1 HPAIV, dramatically reducing the viral shedding, the clinical signs and the pathological outcome. Correlating with the protection afforded, sera from chickens primed with H7N2 LPAIV reacted with the H7-AIV subtype in hemagglutination inhibition assay and specifically with the N2-neuraminidase antigen. Conversely, subsequent exposure to H5N1 HPAIV resulted in a two days-delay on the onset of disease but all chickens died by 7 days post-challenge. Lack of protection correlated with the absence of H5-hemagglutining inhibitory antibodies prior to H5N1 HPAIV challenge. Our data suggest that in naturally occurring outbreaks of HPAIV, birds with pre-existing immunity to LPAIV could survive lethal infections with HA-homologous HPAIV but not subsequent re-infections with HA-heterologous HPAIV. These results could be useful to better understand the dynamics of AIV in chickens and might help in future vaccine formulations.

  6. Novel virus influenza A (H1N1sw in South-Eastern France, April-August 2009.

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    Antoine Nougairède

    Full Text Available BACKGROUND: In April 2009, the first cases of pandemic (H1N1-2009 influenza [H1N1sw] virus were detected in France. Virological surveillance was undertaken in reference laboratories of the seven French Defence Zones. METHODOLOGY/PRINCIPAL FINDINGS: We report results of virological analyses performed in the Public Hospitals of Marseille during the first months of the outbreak. (i Nasal swabs were tested using rapid influenza diagnostic test (RIDT and two RT-PCR assays. Epidemiological characteristics of the 99 first suspected cases were analyzed, including detection of influenza virus and 18 other respiratory viruses. During three months, a total of 1,815 patients were tested (including 236 patients infected H1N1sw virus and distribution in age groups and results of RIDT were analyzed. (ii 600 sera received before April 2009 and randomly selected from in-patients were tested by a standard hemagglutination inhibition assay for antibody to the novel H1N1sw virus. (iii One early (May 2009 and one late (July 2009 viral isolates were characterized by sequencing the complete hemagglutinine and neuraminidase genes. (iiii Epidemiological characteristics of a cluster of cases that occurred in July 2009 in a summer camp were analyzed. CONCLUSIONS/SIGNIFICANCE: This study presents new virological and epidemiological data regarding infection by the pandemic A/H1N1 virus in Europe. Distribution in age groups was found to be similar to that previously reported for seasonal H1N1. The first seroprevalence data made available for a European population suggest a previous exposure of individuals over 40 years old to influenza viruses antigenically related to the pandemic (H1N1-2009 virus. Genomic analysis indicates that strains harbouring a new amino-acid pattern in the neuraminidase gene appeared secondarily and tended to supplant the first strains. Finally, in contrast with previous reports, our data support the use of RIDT for the detection of infection in

  7. Novel Influenza A (H1N1) Virus Infection in Children: Chest Radiographic and CT Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Min Jeong; Lee, Young Seok; Lee, Jee Young; Lee, Kun Song [Dankook University College of Medicine, Dankook University Hospital, Cheonan (Korea, Republic of)

    2010-12-15

    The purpose of this study was to evaluate the chest radiographic and CT findings of novel influenza A (H1N1) virus infection in children, the population that is more vulnerable to respiratory infection than adults. The study population comprised 410 children who were diagnosed with an H1N1 infection from August 24, 2009 to November 11, 2009 and underwent chest radiography at Dankook University Hospital in Korea. Six of these patients also underwent chest CT. The initial chest radiographs were classified as normal or abnormal. The abnormal chest radiographs and high resolution CT scans were assessed for the pattern and distribution of parenchymal lesions, and the presence of complications such as atelectasis, pleural effusion, and pneumomediastinum. The initial chest radiograph was normal in 384 of 410 (94%) patients and abnormal in 26 of 410 (6%) patients. Parenchymal abnormalities seen on the initial chest radiographs included prominent peribronchial marking (25 of 26, 96%), consolidation (22 of 26, 85%), and ground-glass opacities without consolidation (2 of 26, 8%). The involvement was usually bilateral (19 of 26, 73%) with the lower lung zone predominance (22 of 26, 85%). Atelectasis was observed in 12 (46%) and pleural effusion in 11 (42%) patients. CT (n = 6) scans showed peribronchovascular interstitial thickening (n = 6), ground-glass opacities (n = 5), centrilobular nodules (n = 4), consolidation (n = 3), mediastinal lymph node enlargement (n = 5), pleural effusion (n = 3), and pneumomediastinum (n = 3). Abnormal chest radiographs were uncommon in children with a swine-origin influenza A (H1N1) virus (S-OIV) infection. In children, H1N1 virus infection can be included in the differential diagnosis, when chest radiographs and CT scans show prominent peribronchial markings and ill-defined patchy consolidation with mediastinal lymph node enlargement, pleural effusion and pneumomediastinum

  8. Novel Influenza A (H1N1) Virus Infection in Children: Chest Radiographic and CT Evaluation

    International Nuclear Information System (INIS)

    Choi, Min Jeong; Lee, Young Seok; Lee, Jee Young; Lee, Kun Song

    2010-01-01

    The purpose of this study was to evaluate the chest radiographic and CT findings of novel influenza A (H1N1) virus infection in children, the population that is more vulnerable to respiratory infection than adults. The study population comprised 410 children who were diagnosed with an H1N1 infection from August 24, 2009 to November 11, 2009 and underwent chest radiography at Dankook University Hospital in Korea. Six of these patients also underwent chest CT. The initial chest radiographs were classified as normal or abnormal. The abnormal chest radiographs and high resolution CT scans were assessed for the pattern and distribution of parenchymal lesions, and the presence of complications such as atelectasis, pleural effusion, and pneumomediastinum. The initial chest radiograph was normal in 384 of 410 (94%) patients and abnormal in 26 of 410 (6%) patients. Parenchymal abnormalities seen on the initial chest radiographs included prominent peribronchial marking (25 of 26, 96%), consolidation (22 of 26, 85%), and ground-glass opacities without consolidation (2 of 26, 8%). The involvement was usually bilateral (19 of 26, 73%) with the lower lung zone predominance (22 of 26, 85%). Atelectasis was observed in 12 (46%) and pleural effusion in 11 (42%) patients. CT (n = 6) scans showed peribronchovascular interstitial thickening (n = 6), ground-glass opacities (n = 5), centrilobular nodules (n = 4), consolidation (n = 3), mediastinal lymph node enlargement (n = 5), pleural effusion (n = 3), and pneumomediastinum (n = 3). Abnormal chest radiographs were uncommon in children with a swine-origin influenza A (H1N1) virus (S-OIV) infection. In children, H1N1 virus infection can be included in the differential diagnosis, when chest radiographs and CT scans show prominent peribronchial markings and ill-defined patchy consolidation with mediastinal lymph node enlargement, pleural effusion and pneumomediastinum

  9. Tropism and Infectivity of Influenza Virus, Including Highly Pathogenic Avian H5N1 Virus, in Ferret Tracheal Differentiated Primary Epithelial Cell Cultures

    Science.gov (United States)

    Zeng, Hui; Goldsmith, Cynthia S.; Maines, Taronna R.; Belser, Jessica A.; Gustin, Kortney M.; Pekosz, Andrew; Zaki, Sherif R.; Katz, Jacqueline M.

    2013-01-01

    Tropism and adaptation of influenza viruses to new hosts is partly dependent on the distribution of the sialic acid (SA) receptors to which the viral hemagglutinin (HA) binds. Ferrets have been established as a valuable in vivo model of influenza virus pathogenesis and transmission because of similarities to humans in the distribution of HA receptors and in clinical signs of infection. In this study, we developed a ferret tracheal differentiated primary epithelial cell culture model that consisted of a layered epithelium structure with ciliated and nonciliated cells on its apical surface. We found that human-like (α2,6-linked) receptors predominated on ciliated cells, whereas avian-like (α2,3-linked) receptors, which were less abundant, were presented on nonciliated cells. When we compared the tropism and infectivity of three human (H1 and H3) and two avian (H1 and H5) influenza viruses, we observed that the human influenza viruses primarily infected ciliated cells and replicated efficiently, whereas a highly pathogenic avian H5N1 virus (A/Vietnam/1203/2004) replicated efficiently within nonciliated cells despite a low initial infection rate. Furthermore, compared to other influenza viruses tested, VN/1203 virus replicated more efficiently in cells isolated from the lower trachea and at a higher temperature (37°C) compared to a lower temperature (33°C). VN/1203 virus infection also induced higher levels of immune mediator genes and cell death, and virus was recovered from the basolateral side of the cell monolayer. This ferret tracheal differentiated primary epithelial cell culture system provides a valuable in vitro model for studying cellular tropism, infectivity, and the pathogenesis of influenza viruses. PMID:23255802

  10. Pediatric Healthcare Response to Pandemic (H1N1) 2009 Influenza Stakeholder Meeting - Summary of Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    HCTT CHE

    2010-01-01

    The goal of the meeting was to bring together subject matter experts to develop tools and resources for use by the pediatric healthcare community in response to 2009 (H1N1) pandemic influenza activity during the 2009 influenza season.

  11. Desempeño de la prueba de inmunofluorescencia directa en el diagnóstico del virus Influenza A(H1N1) Direct immunofluorescence assay performance in diagnosis of the Influenza A(H1N1) virus

    OpenAIRE

    Luis Pianciola; Gladys González; Melina Mazzeo; Mariano Navello; Natalia Quidel; María Fernanda Bulgheroni

    2010-01-01

    El 25 de abril de 2009, a menos de un mes de la detección en México del primer humano con virus Influenza A(H1N1), la enfermedad ya se había propagado a más de 40 países superando los 10 000 casos notificados. Dada su naturaleza impredecible, este tipo de virus requiere métodos diagnósticos apropiados, confiables y seguros, pero que también estén al alcance de los laboratorios clínicos. Mediante el estudio de 291 muestras de pacientes con sospecha de infección por virus Influenza A(H1N1) en N...

  12. Acute immune thrombocytopenic purpura in an adolescent with 2009 novel H1N1 influenza A virus infection

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    Chun-Yi Lee

    2011-09-01

    Full Text Available Although both leukopenia and thrombocytopenia are not uncommon hematological findings among patients with novel 2009 H1N1 influenza virus infection, immune thrombocytopenic purpura has rarely been shown to be associated with this novel influenza A infection. Here, we describe a previously healthy adolescent who presented with fever, influenza-like symptoms and acute onset of generalized petechiae and active oral mucosa bleeding on the third day of his illness. Severe leukopenia and thrombocytopenia were found. There was neither malignancy nor blast cells found by bone marrow aspiration. Real-time reverse transcriptase polymerase chain reaction was positive for novel 2009 H1N1 influenza infection. Novel influenza-associated atypical immune thrombocytopenic purpura was diagnosed. The patient recovered uneventfully after oseltamivir and methylprednisolone therapy.

  13. Full genomic analysis of an influenza A (H1N2 virus identified during 2009 pandemic in Eastern India: evidence of reassortment event between co-circulating A(H1N1pdm09 and A/Brisbane/10/2007-like H3N2 strains

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    Mukherjee Tapasi Roy

    2012-10-01

    Full Text Available Abstract Background During the pandemic [Influenza A(H1N1pdm09] period in 2009-2010, an influenza A (Inf-A virus with H1N2 subtype (designated as A/Eastern India/N-1289/2009 was detected from a 25 years old male from Mizoram (North-eastern India. Objective To characterize full genome of the H1N2 influenza virus. Methods For initial detection of Influenza viruses, amplification of matrix protein (M gene of Inf-A and B viruses was carried out by real time RT-PCR. Influenza A positive viruses are then further subtyped with HA and NA gene specific primers. Sequencing and the phylogenetic analysis was performed for the H1N2 strain to understand its origin. Results The outcome of this full genome study revealed a unique reassortment event where the N-1289 virus acquired it’s HA gene from a 2009 pandemic H1N1 virus with swine origin and the other genes from H3N2-like viruses of human origin. Conclusions This study provides information on possibility of occurrence of reassortment events during influenza season when infectivity is high and two different subtypes of Inf-A viruses co-circulate in same geographical location.

  14. The chest features of patients with the novel influenza type A H1N1 on high resolution CT

    International Nuclear Information System (INIS)

    Shi Yuxin; Li Shujuan; Zhou Su; Shi Suodi; Zhang Zhiyong

    2010-01-01

    Objective: To explore the chest features of patients with the novel influenza type A H1N1 on HRCT. Methods: One hundred and seventy-two chest HRCT examinations on 163 cases with Influenza type A H1N1 (9 cases were reexamed) were retrospectively analyzed using standard pulmonary window and mediastinal window, respectively. HRCT imaging appearances were summarized. Results: Ninety-seven cases showed normal on chest HRCT, while the others showed abnormalities of parenchymal and interstitial. Among them, HRCT identified ground-glass opacity in 35 cases (53.0%), centrilobular nodules in 30 cases (45.5%), thickening of intralobular septa in 31 cases (47.0%), intralobular thin reticulation and micro-nodule in 8 cases (12.1%), single-lobular inflammation in 19 cases (28.8%), consolidation of lung (the large consolidation and multiple small consolidations) in 15 cases (22.7%), pulmonary atelectasis in 3 cases (4.5%), and irregular lines in 2 cases (3.0%). Pleurisy was also revealed including 8 cases with right pleurisy, 5 cases with left pleurisy, 5 cases with left pleurisy, and 19 cases with bilateral pleurisy. Mediastinal and axillary lymphadenopathy were found in 7 cases, who were spared of pleural effusion. All above abnormalities resolved quickly after anti-virus treatment. Conclusion: Parenchymal and interstitial abnormalities, mediastinum and axillary fossa lymphadenopathy, and pleural effusion were the common findings on HRCT in patients with Influenza type A H1N1, which were similar to those of other viral pneumonia. (authors)

  15. Molecular epidemiology of circulating highly pathogenic avian influenza (H5N1) virus in chickens, in Bangladesh, 2007-2010

    DEFF Research Database (Denmark)

    Ahmed, Syed Sayeem Uddin; Themudo, Goncalo Espregueira Cruz; Christensen, Jens Peter

    2012-01-01

    Bangladesh has been severely hit by highly pathogenic avian influenza H5N1 (HPAI-H5N1). However, little is known about the genetic diversity and the evolution of the circulating viruses in Bangladesh. In the present study, we analyzed the hemagglutinin gene of 30 Bangladeshi chicken isolates from...... several amino acid substitutions, but they are not indicative of adaptation toward human infection. The Mantel correlation test confirmed significant correlation between genetic distances and temporal distances between the viruses. The Bayesian tree shows that isolates from waves 3 and 4 derived from...... virus in Bangladesh. Furthermore, the formation of a subclade capable of transmission to humans cannot be ruled out. The findings of this study might provide valuable information for future surveillance, prevention and control programme....

  16. Penerapan Metode Diagnosis Cepat Virus Avian Influenza H5N1 dengan Metode Single Step Multiplex RT-PCR

    Directory of Open Access Journals (Sweden)

    Aris Haryanto

    2010-12-01

    Full Text Available Avian influenza (AI virus is a segmented single stranded (ss RNA virus with negative polarity andbelong to the Orthomyxoviridae family. Diagnose of AI virus can be performed using conventional methodsbut it has low sensitivity and specificity. The objective of the research was to apply rapid, precise, andaccurate diagnostic method for AI virus and also to determine its type and subtype based on the SingleStep Multiplex Reverse Transcriptase-Polymerase Chain Reaction targeting M, H5, and N1 genes. In thismethod M, H5 and NI genes were simultaneously amplified in one PCR tube. The steps of this researchconsist of collecting viral RNAs from 10 different AI samples originated from Maros Disease InvestigationCenter during 2007. DNA Amplification was conducted by Simplex RT-PCR using M primer set. Then, bysingle step multiplex RT-PCR were conducted simultaneously using M, H5 and N1 primers set. The RTPCRproducts were then separated on 1.5% agarose gel, stained by ethidum bromide and visualized underUV transilluminator. Results showed that 8 of 10 RNA virus samples could be amplified by Simplex RTPCRfor M gene which generating a DNA fragment of 276 bp. Amplification using multiplex RT-PCRmethod showed two of 10 samples were AI positive using multiplex RT-PCR, three DNA fragments weregenerated consisting of 276 bp for M gene, 189 bp for H5 gene, and 131 bp for N1. In this study, rapid andeffective diagnosis method for AI virus can be conducted by using simultaneous Single Step Multiplex RTPCR.By this technique type and subtype of AI virus, can also be determined, especially H5N1.

  17. Outcomes of influenza A(H1N1)pdm09 virus infection

    DEFF Research Database (Denmark)

    Lynfield, Ruth; Davey, Richard; Dwyer, Dominic E

    2014-01-01

    BACKGROUND: Data from prospectively planned cohort studies on risk of major clinical outcomes and prognostic factors for patients with influenza A(H1N1)pdm09 virus are limited. In 2009, in order to assess outcomes and evaluate risk factors for progression of illness, two cohort studies were...

  18. The NS segment of H5N1 avian influenza viruses (AIV) enhances the virulence of an H7N1 AIV in chickens.

    Science.gov (United States)

    Vergara-Alert, Júlia; Busquets, Núria; Ballester, Maria; Chaves, Aida J; Rivas, Raquel; Dolz, Roser; Wang, Zhongfang; Pleschka, Stephan; Majó, Natàlia; Rodríguez, Fernando; Darji, Ayub

    2014-01-25

    Some outbreaks involving highly pathogenic avian influenza viruses (HPAIV) of subtypes H5 and H7 were caused by avian-to-human transmissions. In nature, different influenza A viruses can reassort leading to new viruses with new characteristics. We decided to investigate the impact that the NS-segment of H5 HPAIV would have on viral pathogenicity of a classical avian H7 HPAIV in poultry, a natural host. We focussed this study based on our previous work that demonstrated that single reassortment of the NS-segment from an H5 HPAIV into an H7 HPAIV changes the ability of the virus to replicate in mammalian hosts. Our present data show that two different H7-viruses containing an NS-segment from H5-types (FPV NS GD or FPV NS VN) show an overall highly pathogenic phenotype compared with the wild type H7-virus (FPV), as characterized by higher viral shedding and earlier manifestation of clinical signs. Correlating with the latter, higher amounts of IFN-β mRNA were detected in the blood of NS-reassortant infected birds, 48 h post-infection (pi). Although lymphopenia was detected in chickens from all AIV-infected groups, also 48 h pi those animals challenged with NS-reassortant viruses showed an increase of peripheral monocyte/macrophage-like cells expressing high levels of IL-1β, as determined by flow cytometry. Taken together, these findings highlight the importance of the NS-segment in viral pathogenicity which is directly involved in triggering antiviral and pro-inflammatory cytokines found during HPAIV pathogenesis in chickens.

  19. Seasonal Influenza A H1N1pdm09 Virus and Severe Outcomes: A Reason for Broader Vaccination in Non-Elderly, At-Risk People.

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    Elisa Minchole

    Full Text Available Recent pandemics of influenza A H1N1pdm09 virus have caused severe illness, especially in young people. Very few studies on influenza A H1N1pdm09 in post-pandemic periods exist, and there is no information on the severity of both seasonal influenza A(H1N1 and A(H3N2 from the same season, adjusting for potential confounders, including vaccine.We performed a retrospective observational study of adults hospitalized during the 2014 season with influenza A(H1N1 or A(H3N2. All patients underwent the same diagnostic and therapeutic protocol in a single hospital, including early Oseltamivir therapy. We included 234 patients: 146 (62.4% influenza A(H1N1 and 88 (37.6% A(H3N2. A(H1N1 patients were younger (p<0.01, developed more pneumonia (p<0.01, respiratory complications (p = 0.015, ARDS (p = 0.047, and septic shock (p = 0.049, were more frequently admitted to the ICU (p = 0.022, required IMV (p = 0.049, and were less frequently vaccinated (p = 0.008. After adjusting for age, comorbidities, time from onset of illness, and vaccine status, influenza A(H1N1 (OR, 2.525, coinfection (OR, 2.821, and no vaccination (OR, 3.086 were independent risk factors for severe disease.Hospitalized patients with influenza A(H1N1 were more than twice as likely to have severe influenza. They were younger and most had not received the vaccine. Our findings suggest that seasonal influenza A(H1N1 maintains some features of pandemic viruses, and recommend wider use of vaccination in younger adult high-risk patients.

  20. Antigenic, genetic, and pathogenic characterization of H5N1 highly pathogenic avian influenza viruses isolated from dead whooper swans (Cygnus cygnus) found in northern Japan in 2008.

    Science.gov (United States)

    Okamatsu, Masatoshi; Tanaka, Tomohisa; Yamamoto, Naoki; Sakoda, Yoshihiro; Sasaki, Takashi; Tsuda, Yoshimi; Isoda, Norikazu; Kokumai, Norihide; Takada, Ayato; Umemura, Takashi; Kida, Hiroshi

    2010-12-01

    In April and May 2008, whooper swans (Cygnus cygnus) were found dead in Hokkaido in Japan. In this study, an adult whooper swan found dead beside Lake Saroma was pathologically examined and the identified H5N1 influenza virus isolates were genetically and antigenically analyzed. Pathological findings indicate that the swan died of severe congestive edema in the lungs. Phylogenetic analysis of the HA genes of the isolates revealed that they are the progeny viruses of isolates from poultry and wild birds in China, Russia, Korea, and Hong Kong. Antigenic analyses indicated that the viruses are distinguished from the H5N1 viruses isolated from wild birds and poultry before 2007. The chickens vaccinated with A/duck/Hokkaido/Vac-1/2004 (H5N1) survived for 14 days after challenge with A/whooper swan/Hokkaido/1/2008 (H5N1), although a small amount of the challenge virus was recovered from the tissues of the birds. These findings indicate that H5N1 highly pathogenic avian influenza viruses are circulating in wild birds in addition to domestic poultry in Asia and exhibit antigenic variation that may be due to vaccination.