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  1. H5N1 VLP vaccine induced protection in ferrets against lethal challenge with highly pathogenic H5N1 influenza viruses.

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    Mahmood, Kutubuddin; Bright, Rick A; Mytle, Nutan; Carter, Donald M; Crevar, Corey J; Achenbach, Jenna E; Heaton, Penny M; Tumpey, Terrence M; Ross, Ted M

    2008-10-03

    In this study, recombinant virus-like particles (VLPs) were evaluated as a candidate vaccine against emerging influenza viruses with pandemic potential. The VLPs are composed of the hemagglutinin (HA), neuraminidase (NA), and matrix 1 (M1) proteins of the H5N1 A/Indonesia/05/2005 (clade 2.1; [Indo/05]) virus, which were expressed using baculovirus in Spodoptera frugiperda (Sf9) cells. Ferrets received either 2 injections of the VLP vaccine at escalating doses (based on HA content), recombinant HA, or were mock vaccinated. Vaccinated ferrets were then challenged with either H5N1 Indo/05 or H5N1 A/Viet Nam 1203/2004 (VN/04) wild-type viruses. All ferrets that received the VLP vaccine survived regardless of the VLP dose or challenge strain, whereas seven of eight mock vaccinated ferrets died. The VLP vaccine induced HAI antibodies against the homologous H5N1 clade 2.1 strain, as well as heterologous strains from H5N1 clades 1, 2.2, and 2.3. The magnitude of the HAI titers correlated with VLP dose. Neutralizing antibody responses against the Indo/05 and VN/04 strains showed a similar pattern. Affinity of the anti-HA antibodies raised by the H5N1 Indo/05 VLPs had a higher association rate to the homologous clade 2.1 HA than to the clade 1 (VN/04) HA; however, once bound, antibodies had similar slow disassociation rates. These results provide support for continued development of the H5N1 VLPs as a candidate vaccine against pandemic influenza. Exploration of immunologic correlates of protection for H5N1 vaccines beyond HAI and neutralizing antibody responses is warranted.

  2. A recombinant vaccine of H5N1 HA1 fused with foldon and human IgG Fc induced complete cross-clade protection against divergent H5N1 viruses.

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    Lanying Du

    Full Text Available Development of effective vaccines to prevent influenza, particularly highly pathogenic avian influenza (HPAI caused by influenza A virus (IAV subtype H5N1, is a challenging goal. In this study, we designed and constructed two recombinant influenza vaccine candidates by fusing hemagglutinin 1 (HA1 fragment of A/Anhui/1/2005(H5N1 to either Fc of human IgG (HA1-Fc or foldon plus Fc (HA1-Fdc, and evaluated their immune responses and cross-protection against divergent strains of H5N1 virus. Results showed that these two recombinant vaccines induced strong immune responses in the vaccinated mice, which specifically reacted with HA1 proteins and an inactivated heterologous H5N1 virus. Both proteins were able to cross-neutralize infections by one homologous strain (clade 2.3 and four heterologous strains belonging to clades 0, 1, and 2.2 of H5N1 pseudoviruses as well as three heterologous strains (clades 0, 1, and 2.3.4 of H5N1 live virus. Importantly, immunization with these two vaccine candidates, especially HA1-Fdc, provided complete cross-clade protection against high-dose lethal challenge of different strains of H5N1 virus covering clade 0, 1, and 2.3.4 in the tested mouse model. This study suggests that the recombinant fusion proteins, particularly HA1-Fdc, could be developed into an efficacious universal H5N1 influenza vaccine, providing cross-protection against infections by divergent strains of highly pathogenic H5N1 virus.

  3. H5N1 whole-virus vaccine induces neutralizing antibodies in humans which are protective in a mouse passive transfer model.

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    M Keith Howard

    Full Text Available BACKGROUND: Vero cell culture-derived whole-virus H5N1 vaccines have been extensively tested in clinical trials and consistently demonstrated to be safe and immunogenic; however, clinical efficacy is difficult to evaluate in the absence of wide-spread human disease. A lethal mouse model has been utilized which allows investigation of the protective efficacy of active vaccination or passive transfer of vaccine induced sera following lethal H5N1 challenge. METHODS: We used passive transfer of immune sera to investigate antibody-mediated protection elicited by a Vero cell-derived, non-adjuvanted inactivated whole-virus H5N1 vaccine. Mice were injected intravenously with H5N1 vaccine-induced rodent or human immune sera and subsequently challenged with a lethal dose of wild-type H5N1 virus. RESULTS: Passive transfer of H5N1 vaccine-induced mouse, guinea pig and human immune sera provided dose-dependent protection of recipient mice against lethal challenge with wild-type H5N1 virus. Protective dose fifty values for serum H5N1 neutralizing antibody titers were calculated to be ≤1∶11 for all immune sera, independently of source species. CONCLUSIONS: These data underpin the confidence that the Vero cell culture-derived, whole-virus H5N1 vaccine will be effective in a pandemic situation and support the use of neutralizing serum antibody titers as a correlate of protection for H5N1 vaccines.

  4. Avian influenza vaccines against H5N1 'bird flu'.

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    Li, Chengjun; Bu, Zhigao; Chen, Hualan

    2014-03-01

    H5N1 avian influenza viruses (AIVs) have spread widely to more than 60 countries spanning three continents. To control the disease, vaccination of poultry is implemented in many of the affected countries, especially in those where H5N1 viruses have become enzootic in poultry and wild birds. Recently, considerable progress has been made toward the development of novel avian influenza (AI) vaccines, especially recombinant virus vector vaccines and DNA vaccines. Here, we will discuss the recent advances in vaccine development and use against H5N1 AIV in poultry. Understanding the properties of the available, novel vaccines will allow for the establishment of rational vaccination protocols, which in turn will help the effective control and prevention of H5N1 AI.

  5. Broad Clade 2 cross-reactive immunity induced by an adjuvanted clade 1 rH5N1 pandemic influenza vaccine.

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    Isabel Leroux-Roels

    Full Text Available BACKGROUND: The availability of H5N1 vaccines that can elicit a broad cross-protective immunity against different currently circulating clade 2 H5N1 viruses is a pre-requisite for the development of a successful pre-pandemic vaccination strategy. In this regard, it has recently been shown that adjuvantation of a recombinant clade 1 H5N1 inactivated split-virion vaccine with an oil-in-water emulsion-based adjuvant system also promoted cross-immunity against a recent clade 2 H5N1 isolate (A/Indonesia/5/2005, subclade 2.1. Here we further analyse the cross-protective potential of the vaccine against two other recent clade 2 isolates (A/turkey/Turkey/1/2005 and A/Anhui/1/2005 which are, as defined by WHO, representatives of subclades 2.2 and 2.3 respectively. METHODS AND FINDINGS: Two doses of the recombinant A/Vietnam/1194/2004 (H5N1, clade 1 vaccine were administered 21 days apart to volunteers aged 18-60 years. We studied the cross-clade immunogenicity of the lowest antigen dose (3.8 microg haemagglutinin given with (N = 20 or without adjuvant (N = 20. Immune responses were assessed at 21 days following the first and second vaccine doses and at 6 months following first vaccination. Vaccination with two doses of 3.8 microg of the adjuvanted vaccine induced four-fold neutralising seroconversion rates in 85% of subjects against A/turkey/Turkey/1/2005 (subclade 2.2 and 75% of subjects against A/Anhui/1/2005 (subclade 2.3 recombinant strains. There was no response induced against these strains in the non-adjuvanted group. At 6 months following vaccination, 70% and 60% of subjects retained neutralising antibodies against the recombinant subclade 2.2 and 2.3 strains, respectively and 40% of subjects retained antibodies against the recombinant subclade 2.1 A/Indonesia/5/2005 strain. CONCLUSIONS: In addition to antigen dose-sparing, adjuvantation of inactivated split H5N1 vaccine promotes broad and persistent cross-clade immunity which is a pre

  6. Adjuvanted H5N1 vaccine induces early CD4+ T cell response that predicts long-term persistence of protective antibody levels.

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    Galli, Grazia; Medini, Duccio; Borgogni, Erica; Zedda, Luisanna; Bardelli, Monia; Malzone, Carmine; Nuti, Sandra; Tavarini, Simona; Sammicheli, Chiara; Hilbert, Anne K; Brauer, Volker; Banzhoff, Angelika; Rappuoli, Rino; Del Giudice, Giuseppe; Castellino, Flora

    2009-03-10

    Immune responses to vaccination are tested in clinical trials. This process usually requires years especially when immune memory and persistence are analyzed. Markers able to quickly predict the immune response would be very useful, particularly when dealing with emerging diseases that require a rapid response, such as avian influenza. To address this question we vaccinated healthy adults at days 1, 22, and 202 with plain or MF59-adjuvanted H5N1 subunit vaccines and tested both cell-mediated and antibody responses up to day 382. Only the MF59-H5N1 vaccine induced high titers of neutralizing antibodies, a large pool of memory H5N1-specific B lymphocytes, and H5-CD4(+) T cells broadly reactive with drifted H5. The CD4(+) response was dominated by IL-2(+) IFN-gamma(-) IL-13(-) T cells. Remarkably, a 3-fold increase in the frequency of virus-specific total CD4(+) T cells, measurable after 1 dose, accurately predicted the rise of neutralizing antibodies after booster immunization and their maintenance 6 months later. We suggest that CD4(+) T cell priming might be used as an early predictor of the immunogenicity of prepandemic vaccines.

  7. A single immunization with HA DNA vaccine by electroporation induces early protection against H5N1 avian influenza virus challenge in mice

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    Chen Jianjun

    2009-02-01

    Full Text Available Abstract Background Developing vaccines for the prevention of human infection by H5N1 influenza viruses is an urgent task. DNA vaccines are a novel alternative to conventional vaccines and should contribute to the prophylaxis of emerging H5N1 virus. In this study, we assessed whether a single immunization with plasmid DNA expressing H5N1 hemagglutinin (HA could provide early protection against lethal challenge in a mouse model. Methods Mice were immunized once with HA DNA at 3, 5, 7 days before a lethal challenge. The survival rate, virus titer in the lungs and change of body weight were assayed to evaluate the protective abilities of the vaccine. To test the humoral immune response induced by HA DNA, serum samples were collected through the eye canthus of mice on various days after immunization and examined for specific antibodies by ELISA and an HI assay. Splenocytes were isolated after the immunization to determine the antigen-specific T-cell response by the ELISPOT assay. Results Challenge experiments revealed that a single immunization of H5N1 virus HA DNA is effective in early protection against lethal homologous virus. Immunological analysis showed that an antigen-specific antibody and T-cell response could be elicited in mice shortly after the immunization. The protective abilities were correlated with the amount of injected DNA and the length of time after vaccination. Conclusion A single immunization of 100 μg H5 HA DNA vaccine combined with electroporation was able to provide early protection in mice against homologous virus infection.

  8. Immunogenicity and protective efficacy of a live attenuated H5N1 vaccine in nonhuman primates.

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    Shufang Fan

    2009-05-01

    Full Text Available The continued spread of highly pathogenic H5N1 influenza viruses among poultry and wild birds, together with the emergence of drug-resistant variants and the possibility of human-to-human transmission, has spurred attempts to develop an effective vaccine. Inactivated subvirion or whole-virion H5N1 vaccines have shown promising immunogenicity in clinical trials, but their ability to elicit protective immunity in unprimed human populations remains unknown. A cold-adapted, live attenuated vaccine with the hemagglutinin (HA and neuraminidase (NA genes of an H5N1 virus A/VN/1203/2004 (clade 1 was protective against the pulmonary replication of homologous and heterologous wild-type H5N1 viruses in mice and ferrets. In this study, we used reverse genetics to produce a cold-adapted, live attenuated H5N1 vaccine (AH/AAca that contains HA and NA genes from a recent H5N1 isolate, A/Anhui/2/05 virus (AH/05 (clade 2.3, and the backbone of the cold-adapted influenza H2N2 A/AnnArbor/6/60 virus (AAca. AH/AAca was attenuated in chickens, mice, and monkeys, and it induced robust neutralizing antibody responses as well as HA-specific CD4+ T cell immune responses in rhesus macaques immunized twice intranasally. Importantly, the vaccinated macaques were fully protected from challenge with either the homologous AH/05 virus or a heterologous H5N1 virus, A/bar-headed goose/Qinghai/3/05 (BHG/05; clade 2.2. These results demonstrate for the first time that a cold-adapted H5N1 vaccine can elicit protective immunity against highly pathogenic H5N1 virus infection in a nonhuman primate model and provide a compelling argument for further testing of double immunization with live attenuated H5N1 vaccines in human trials.

  9. Role of vaccination-induced immunity and antigenic distance in the transmission dynamics of highly pathogenic avian influenza H5N1.

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    Sitaras, Ioannis; Rousou, Xanthoula; Kalthoff, Donata; Beer, Martin; Peeters, Ben; de Jong, Mart C M

    2016-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 epidemics in poultry cause huge economic losses as well as sporadic human morbidity and mortality. Vaccination in poultry has often been reported as being ineffective in preventing transmission and as a potential driving force in the selection of immune escape mutants. We conducted transmission experiments to evaluate the transmission dynamics of HPAI H5N1 strains in chickens vaccinated with high and low doses of immune escape mutants we have previously selected, and analysed the data using mathematical models. Remarkably, we demonstrate that the effect of antigenic distances between the vaccine and challenge strains used in this study is too small to influence the transmission dynamics of the strains used. This is because the effect of a sufficient vaccine dose on antibody levels against the challenge viruses is large enough to compensate for any decrease in antibody titres due to antigenic differences between vaccine and challenge strains. Our results show that at least under experimental conditions, vaccination will remain effective even after antigenic changes as may be caused by the initial selection in vaccinated birds.

  10. Adenovirus-based vaccines against avian-origin H5N1 influenza viruses.

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    He, Biao; Zheng, Bo-jian; Wang, Qian; Du, Lanying; Jiang, Shibo; Lu, Lu

    2015-02-01

    Since 1997, human infection with avian H5N1, having about 60% mortality, has posed a threat to public health. In this review, we describe the epidemiology of H5N1 transmission, advantages and disadvantages of different influenza vaccine types, and characteristics of adenovirus, finally summarizing advances in adenovirus-based H5N1 systemic and mucosal vaccines.

  11. Progress toward a universal H5N1 vaccine: a recombinant modified vaccinia virus Ankara-expressing trivalent hemagglutinin vaccine.

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    Mookkan Prabakaran

    Full Text Available The rapid evolution of new sublineages of H5N1 influenza poses the greatest challenge in control of H5N1 infection by currently existing vaccines. To overcome this, an MVAtor vector expressing three H5HA antigens A/Vietnam/1203/04, A/Indonesia/669/06 and A/Anhui/01/05 (MVAtor-tri-HA vector was developed to elicit broad cross-protection against diverse clades by covering amino acid variations in the major neutralizing epitopes of HA among H5N1 subtypes.BALB/c mice and guinea pigs were immunized i.m. with 8×107 TCID50/animal of MVAtor-tri-HA vector. The immunogenicity and cross-protective immunity of the MVAtor-tri-HA vector was evaluated against diverse clades of H5N1 strains.The results showed that mice immunized with MVAtor-tri-HA vector induced robust cross-neutralizing immunity to diverse H5N1 clades. In addition, the MVAtor-tri-HA vector completely protected against 10 MLD50 of a divergent clade of H5N1 infection (clade 7. Importantly, the serological surveillance of post-vaccinated guinea pig sera demonstrated that MVAtor-tri-HA vector was able to elicit strong cross-clade neutralizing immunity against twenty different H5N1 strains from six clades that emerged between 1997 and 2012.The present findings revealed that incorporation of carefully selected HA genes from divergent H5N1 strains within a single vector could be an effective approach in developing a vaccine with broad coverage to prevent infection during a pandemic situation.

  12. Genetic drift evolution under vaccination pressure among H5N1 Egyptian isolates

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    Afifi Manal A; Abdel-Moneim Ahmed S; El-Kady Magdy F

    2011-01-01

    Background The highly pathogenic H5N1 is a major avian pathogen that intensively affects the poultry industry in Egypt even in spite of the adoption of vaccination strategy. Antigenic drift is among the strategies the influenza virus uses to escape the immune system that might develop due to the pressure of extensive vaccination. H5N1 mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences such an eventual...

  13. Protective efficacy of an H5N1 DNA vaccine against challenge with a lethal H5N1 virus in quail.

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    Li, Junping; Jiang, Yongping; Zhao, Shuangcheng; Chang, Xiaofei; Liu, Jinxiong; Zeng, Xianying; Li, Yanbing; Chen, Hualan

    2012-12-01

    Some H5N1 avian influenza viruses (AIVs) are lethal to quail; however, the use of inactivated vaccines in these birds is largely restricted because of side effects caused by oil adjuvants. Here we evaluated the protective efficacy of a DNA vaccine against lethal challenge with H5N1 highly pathogenic avian influenza virus (HPAIV) in quail. Groups of ten 3-wk-old quail were intramuscularly inoculated three times at 3-wk intervals with 10, 15, 30, or 60 microg, respectively, of plasmid pCAGGoptiHA, which expresses a codon-optimized hemagglutinin gene of the H5N1 virus A/goose/Guangdong/1/96 (GS/GD/96). The control group was inoculated with phosphate-buffered saline. Hemagglutination-inhibition (HI) antibodies were monitored every week after the primary vaccination. The quail were challenged intranasally with 10(5) EID50 of heterologous HPAIV A/duck/Fujian/31/2007 (DK/ FJ/31) (H5N1) 2 wk after the third inoculation. Oropharyngeal and cloacal swab specimens were collected 3, 5, and 7 days after inoculation, and quail were observed daily for disease signs and death for 2 wk. The quail showed no side effects after the plasmid inoculation, and HI antibodies were detectable 1 wk after the second vaccination in all groups and increased sharply after the third inoculation. All quail in the PBS-inoculated group and 20% of the birds in the 10 microg plasmid-inoculated group died after the lethal H5N1 virus challenge; however, birds in the 15, 30, and 60 jg plasmid-inoculated groups were completely protected. These results indicate that this DNA vaccine holds promise for use in quail to protect against H5N1 AIV.

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

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    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.

  15. 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.

  16. 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.

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

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    Benoît Baras

    Full Text Available BACKGROUND: 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 produced rapidly and in sufficient quantities. Potential pandemic inactivated vaccines will ideally induce substantial intra-subtypic cross-protection in humans to warrant the option of use, either prior to or just after the start of a pandemic outbreak. In the present study, we evaluated a split H5N1 A/H5N1/Vietnam/1194/04, clade 1 candidate vaccine, adjuvanted with a proprietary oil-in- water emulsion based Adjuvant System proven to be well-tolerated and highly immunogenic in the human (Leroux-Roels et al. (2007 The Lancet 370:580-589, for its ability to induce intra-subtypic cross-protection against clade 2 H5N1/A/Indonesia/5/05 challenge in ferrets. METHODOLOGY AND PRINCIPAL FINDINGS: All ferrets in control groups receiving non-adjuvanted vaccine or adjuvant alone failed to develop specific or cross-reactive neutralizing antibodies and all died or had to be euthanized within four days of virus challenge. Two doses of adjuvanted split H5N1 vaccine containing >or=1.7 microg HA induced neutralizing antibodies in the majority of ferrets to both clade 1 (17/23 (74% responders and clade 2 viruses (14/23 (61% responders, and 96% (22/23 of vaccinees survived the lethal challenge. Furthermore lung virus loads and viral shedding in the upper respiratory tract were reduced in vaccinated animals relative to controls suggesting that vaccination might also confer a reduced risk of viral transmission. CONCLUSION: These protection data in a stringent challenge model in association with an excellent clinical profile highlight the potential of this adjuvanted H5N1 candidate vaccine as an effective tool in pandemic preparedness.

  18. New strategies for the development of H5N1 subtype influenza vaccines: progress and challenges.

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    Steel, John

    2011-10-01

    The emergence and spread of highly pathogenic avian influenza (H5N1) viruses among poultry in Asia, the Middle East, and Africa have fueled concerns of a possible human pandemic, and spurred efforts towards developing vaccines against H5N1 influenza viruses, as well as improving vaccine production methods. In recent years, promising experimental reverse genetics-derived H5N1 live attenuated vaccines have been generated and characterized, including vaccines that are attenuated through temperature-sensitive mutation, modulation of the interferon antagonist protein, or disruption of the M2 protein. Live attenuated influenza virus vaccines based on each of these modalities have conferred protection against homologous and heterologous challenge in animal models of influenza virus infection. Alternative vaccine strategies that do not require the use of live virus, such as virus-like particle (VLP) and DNA-based vaccines, have also been vigorously pursued in recent years. Studies have demonstrated that influenza VLP vaccination can confer homologous and heterologous protection from lethal challenge in a mouse model of infection. There have also been improvements in the formulation and production of vaccines following concerns over the threat of H5N1 influenza viruses. The use of novel substrates for the growth of vaccine virus stocks has been intensively researched in recent years, and several candidate cell culture-based systems for vaccine amplification have emerged, including production systems based on Madin-Darby canine kidney, Vero, and PerC6 cell lines. Such systems promise increased scalability of product, and reduced reliance on embryonated chicken eggs as a growth substrate. Studies into the use of adjuvants have shown that oil-in-water-based adjuvants can improve the immunogenicity of inactivated influenza vaccines and conserve antigen in such formulations. Finally, efforts to develop more broadly cross-protective immunization strategies through the inclusion

  19. Genetic drift evolution under vaccination pressure among H5N1 Egyptian isolates

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    Afifi Manal A

    2011-06-01

    Full Text Available Background The highly pathogenic H5N1 is a major avian pathogen that intensively affects the poultry industry in Egypt even in spite of the adoption of vaccination strategy. Antigenic drift is among the strategies the influenza virus uses to escape the immune system that might develop due to the pressure of extensive vaccination. H5N1 mutates in an intensified manner and is considered a potential candidate for the possible next pandemic with all the catastrophic consequences such an eventuality will entail. Methods H5N1 was isolated from the pooled organ samples of four different affected flocks in specific pathogen free embryonated chicken eggs (SPF-ECE. A reverse transcriptase polymerase chain reaction (RT-PCR was performed to the haemagglutingin and neuraminidase. Sequencing of the full length haemagglutingin was performed. Sequence analyses of the isolated strains were performed and compared to all available H5N1 from Egyptian human and avian strains in the flu database. Changes in the different amino acid that may be related to virus virulence, receptor affinity and epitope configuration were assigned and matched with all available Egyptian strains in the flu database. Results One out of the four strains was found to be related to the B2 Egyptian lineage, 2 were related to A1 lineage and the 4th was related to A2 lineage. Comparing data obtained from the current study by other available Egyptian H5N1 sequences remarkably demonstrates that amino acid changes in the immune escape variants are remarkably restricted to a limited number of locations on the HA molecule during antigenic drift. Molecular diversity in the HA gene, in relevance to different epitopes, were not found to follow a regular trend, suggesting abrupt cumulative sequence mutations. However a number of amino acids were found to be subjected to high mutation pressure. Conclusion The current data provides a comprehensive view of HA gene evolution among H5N1 subtype viruses in

  20. Intranasal H5N1 vaccines, adjuvanted with chitosan derivatives, protect ferrets against highly pathogenic influenza intranasal and intratracheal challenge.

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    Alex J Mann

    Full Text Available We investigated the protective efficacy of two intranasal chitosan (CSN and TM-CSN adjuvanted H5N1 Influenza vaccines against highly pathogenic avian Influenza (HPAI intratracheal and intranasal challenge in a ferret model. Six groups of 6 ferrets were intranasally vaccinated twice, 21 days apart, with either placebo, antigen alone, CSN adjuvanted antigen, or TM-CSN adjuvanted antigen. Homologous and intra-subtypic antibody cross-reacting responses were assessed. Ferrets were inoculated intratracheally (all treatments or intranasally (CSN adjuvanted and placebo treatments only with clade 1 HPAI A/Vietnam/1194/2004 (H5N1 virus 28 days after the second vaccination and subsequently monitored for morbidity and mortality outcomes. Clinical signs were assessed and nasal as well as throat swabs were taken daily for virology. Samples of lung tissue, nasal turbinates, brain, and olfactory bulb were analysed for the presence of virus and examined for histolopathological findings. In contrast to animals vaccinated with antigen alone, the CSN and TM-CSN adjuvanted vaccines induced high levels of antibodies, protected ferrets from death, reduced viral replication and abrogated disease after intratracheal challenge, and in the case of CSN after intranasal challenge. In particular, the TM-CSN adjuvanted vaccine was highly effective at eliciting protective immunity from intratracheal challenge; serologically, protective titres were demonstrable after one vaccination. The 2-dose schedule with TM-CSN vaccine also induced cross-reactive antibodies to clade 2.1 and 2.2 H5N1 viruses. Furthermore ferrets immunised with TM-CSN had no detectable virus in the respiratory tract or brain, whereas there were signs of virus in the throat and lungs, albeit at significantly reduced levels, in CSN vaccinated animals. This study demonstrated for the first time that CSN and in particular TM-CSN adjuvanted intranasal vaccines have the potential to protect against significant

  1. Two Types of Antibodies Are Induced by Vaccination with A/California/2009pdm Virus: Binding near the Sialic Acid-Binding Pocket and Neutralizing Both H1N1 and H5N1 Viruses

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    Ohshima, Nobuko; Kubota-Koketsu, Ritsuko; Iba, Yoshitaka; Okuno, Yoshinobu; Kurosawa, Yoshikazu

    2014-01-01

    Many people have a history of catching the flu several times during childhood but no additional flu in adulthood, even without vaccination. We analyzed the total repertoire of antibodies (Abs) against influenza A group 1 viruses induced in such a flu-resistant person after vaccination with 2009 H1N1 pandemic influenza virus. They were classified into two types, with no exceptions. The first type, the products of B cells newly induced through vaccination, binds near the sialic acid-binding pocket. The second type, the products of long-lived memory B cells established before vaccination, utilizes the 1-69 VH gene, binds to the stem of HA, and neutralizes both H1N1 and H5N1 viruses with few exceptions. These observations indicate that the sialic acid-binding pocket and its surrounding region are immunogenically very potent and majority of the B cells whose growth is newly induced by vaccination produce Abs that recognize these regions. However, they play a role in protection against influenza virus infection for a short period since variant viruses that have acquired resistance to these Abs become dominant. On the other hand, although the stem of HA is immunogenically not potent, the second type of B cells eventually becomes dominant. Thus, a selection system should function in forming the repertoire of long-lived memory B cells and the stability of the epitope would greatly affect the fate of the memory cells. Acquisition of the ability to produce Abs that bind to the stable epitope could be a major factor of flu resistance. PMID:24505283

  2. Two types of antibodies are induced by vaccination with A/California/2009 pdm virus: binding near the sialic acid-binding pocket and neutralizing both H1N1 and H5N1 viruses.

    Directory of Open Access Journals (Sweden)

    Nobuko Ohshima

    Full Text Available Many people have a history of catching the flu several times during childhood but no additional flu in adulthood, even without vaccination. We analyzed the total repertoire of antibodies (Abs against influenza A group 1 viruses induced in such a flu-resistant person after vaccination with 2009 H1N1 pandemic influenza virus. They were classified into two types, with no exceptions. The first type, the products of B cells newly induced through vaccination, binds near the sialic acid-binding pocket. The second type, the products of long-lived memory B cells established before vaccination, utilizes the 1-69 VH gene, binds to the stem of HA, and neutralizes both H1N1 and H5N1 viruses with few exceptions. These observations indicate that the sialic acid-binding pocket and its surrounding region are immunogenically very potent and majority of the B cells whose growth is newly induced by vaccination produce Abs that recognize these regions. However, they play a role in protection against influenza virus infection for a short period since variant viruses that have acquired resistance to these Abs become dominant. On the other hand, although the stem of HA is immunogenically not potent, the second type of B cells eventually becomes dominant. Thus, a selection system should function in forming the repertoire of long-lived memory B cells and the stability of the epitope would greatly affect the fate of the memory cells. Acquisition of the ability to produce Abs that bind to the stable epitope could be a major factor of flu resistance.

  3. Highly immunogenic prime–boost DNA vaccination protects chickens against challenge with homologous and heterologous H5N1 virus

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    Anna Stachyra

    2014-01-01

    Full Text Available Highly pathogenic avian influenza viruses (HPAIVs cause huge economic losses in the poultry industry because of high mortality rate in infected flocks and trade restrictions. Protective antibodies, directed mainly against hemagglutinin (HA, are the primary means of protection against influenza outbreaks. A recombinant DNA vaccine based on the sequence of H5 HA from the H5N1/A/swan/Poland/305-135V08/2006 strain of HPAIV was prepared. Sequence manipulation included deletion of the proteolytic cleavage site to improve protein stability, codon usage optimization to improve translation and stability of RNA in host cells, and cloning into a commercially available vector to enable expression in animal cells. Naked plasmid DNA was complexed with a liposomal carrier and the immunization followed the prime–boost strategy. The immunogenic potential of the DNA vaccine was first proved in broilers in near-to-field conditions resembling a commercial farm. Next, the protective activity of the vaccine was confirmed in SPF layer-type chickens. Experimental infections (challenge experiments indicated that 100% of vaccinated chickens were protected against H5N1 of the same clade and that 70% of them were protected against H5N1 influenza virus of a different clade. Moreover, the DNA vaccine significantly limited (or even eliminated transmission of the virus to contact control chickens. Two intramuscular doses of DNA vaccine encoding H5 HA induced a strong protective response in immunized chicken. The effective protection lasted for a minimum 8 weeks after the second dose of the vaccine and was not limited to the homologous H5N1 virus. In addition, the vaccine reduced shedding of the virus.

  4. Addition of N-glycosylation sites on the globular head of the H5 hemagglutinin induces the escape of highly pathogenic avian influenza A H5N1 viruses from vaccine-induced immunity.

    Science.gov (United States)

    Hervé, Pierre-Louis; Lorin, Valérie; Jouvion, Grégory; Da Costa, Bruno; Escriou, Nicolas

    2015-12-01

    Highly pathogenic avian influenza A H5N1 viruses remain endemic in poultry in several countries and still constitute a pandemic threat. Since the early 20th century, we experienced four influenza A pandemics. H3N2 and H1N1pdm09 viruses that respectively emerged during 1968 and 2009 pandemics are still responsible for seasonal epidemics. These viruses evolve regularly by substitutions in antigenic sites of the hemagglutinin (HA), which prevent neutralization by antibodies directed against previous strains (antigenic drift). For seasonal H3N2 viruses, an addition of N-glycosylation sites (glycosites) on H3 contributed to this drift. Here, we questioned whether additional glycosites on H5 could induce an escape of H5N1 virus from neutralization, as it was observed for seasonal H3N2 viruses. Seven H5N1 mutants were produced by adding glycosites on H5. The most glycosylated virus escaped from neutralizing antibodies, in vitro and in vivo. Furthermore, a single additional glycosite was responsible for this escape.

  5. Oral priming with replicating adenovirus serotype 4 followed by subunit H5N1 vaccine boost promotes antibody affinity maturation and expands H5N1 cross-clade neutralization.

    Science.gov (United States)

    Khurana, Surender; Coyle, Elizabeth M; Manischewitz, Jody; King, Lisa R; Ishioka, Glenn; Alexander, Jeff; Smith, Jon; Gurwith, Marc; Golding, Hana

    2015-01-01

    A Phase I trial conducted in 2009-2010 demonstrated that oral vaccination with a replication competent Ad4-H5 (A/Vietnam) vector with dosages ranging from 107-1011 viral particles was well tolerated. HA-specific T-cell responses were efficiently induced, but very limited hemagglutination-inhibiting (HI) humoral responses were measured. However, a single boost of Ad4-H5-Vtn vaccinated individuals with a unadjuvanted licensed H5N1 (A/Vietnam) subunit vaccine resulted in superior HI titers compared with unprimed subjects. In the current study, the impact of Ad4-H5 priming on the quality of the polyclonal humoral immune response was evaluated using a real-time kinetics assay by surface plasmon resonance (SPR). Total binding of serum polyclonal antibodies from the Ad4-H5-Vtn primed groups against both homologous H5N1-A/Vietnam/1194/2004 (clade 1) and heterologous A/Indonesia-5/2005 (clade 2.1) HA1 head domain was significantly higher compared with sera from individuals that received subunit H5N1 vaccination alone. SPR measurements also demonstrated that the antigen-antibody complex dissociation rates (a surrogate for antibody affinity) of serum antibodies against the HA1 of H5N1-A/Vietnam were significantly higher in the Ad4-H5 primed groups compared with those from the unprimed group. Furthermore, strong correlations were observed between the antibody affinities for HA1 (but not HA2) and the virus neutralization titers against the homologous strain and a panel of heterologous clade 2 H5N1 strains. These findings support the concept of oral prime-boost vaccine approaches against pandemic influenza to elicit long-term memory B cells with high affinity capable of rapid response to variant pandemic viruses likely to emerge and adapt to human transmissions.

  6. Oral priming with replicating adenovirus serotype 4 followed by subunit H5N1 vaccine boost promotes antibody affinity maturation and expands H5N1 cross-clade neutralization.

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    Surender Khurana

    Full Text Available A Phase I trial conducted in 2009-2010 demonstrated that oral vaccination with a replication competent Ad4-H5 (A/Vietnam vector with dosages ranging from 107-1011 viral particles was well tolerated. HA-specific T-cell responses were efficiently induced, but very limited hemagglutination-inhibiting (HI humoral responses were measured. However, a single boost of Ad4-H5-Vtn vaccinated individuals with a unadjuvanted licensed H5N1 (A/Vietnam subunit vaccine resulted in superior HI titers compared with unprimed subjects. In the current study, the impact of Ad4-H5 priming on the quality of the polyclonal humoral immune response was evaluated using a real-time kinetics assay by surface plasmon resonance (SPR. Total binding of serum polyclonal antibodies from the Ad4-H5-Vtn primed groups against both homologous H5N1-A/Vietnam/1194/2004 (clade 1 and heterologous A/Indonesia-5/2005 (clade 2.1 HA1 head domain was significantly higher compared with sera from individuals that received subunit H5N1 vaccination alone. SPR measurements also demonstrated that the antigen-antibody complex dissociation rates (a surrogate for antibody affinity of serum antibodies against the HA1 of H5N1-A/Vietnam were significantly higher in the Ad4-H5 primed groups compared with those from the unprimed group. Furthermore, strong correlations were observed between the antibody affinities for HA1 (but not HA2 and the virus neutralization titers against the homologous strain and a panel of heterologous clade 2 H5N1 strains. These findings support the concept of oral prime-boost vaccine approaches against pandemic influenza to elicit long-term memory B cells with high affinity capable of rapid response to variant pandemic viruses likely to emerge and adapt to human transmissions.

  7. Protection level of AI H5N1 vaccine clade 2.1.3 commercial against AI H5N1 clade 2.3.2 virus from Ducks to SPF chicken in laboratory conditions

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    Indriani R

    2015-03-01

    Full Text Available Highly Pathogenic Avian Influenza (HPAI subtype H5N1 clade 2.3.2 has infected chickens in farms, causing mortality and a decrease in egg production. Vaccination is one of the strategies to control disease of AI subtype H5N1. AI H5N1 clade 2.1.3 vaccine is available commercially. The effectiveness of two vaccines of AI H5N1 clade 2.1.3 (product A and B, and AI H5N1 clade 2.3.2 (Sukoharjo against AI H5N1 clade 2.3.2 (Sukoharjo virus SPF chickens was tested in laboratory. Four groups of SPF chickens were used in this study, there were (1 vaccinated with H5N1 clade 2.1.3 (product A, (2 vaccinated with H5N1 clade 2.1.3 (product B, (3 vaccinated with AI H5N1 clade 2.3.2 and (4 unvaccinated (as a control. Each vaccinated group consisted of 10 chicken except 8 chicken for control group. SPF chicken were vaccinated with 1 dose of vaccine at 3 weeks olds, and then after 3 weeks post vaccination (at 6 weeks olds. All group of chicken were challenged with 106 EID50 per 0.1 ml via intranasal. The results showed, chicken vaccinated with H5N1 clade 2.1.3 product A and B gave 100 and 80% protection respectively, but showed challenged virus shedding, whereas vaccine of H5N1 clade 2.3.2 gave 100% protection from mortality and without virus shedding. Vaccines of AI H5N1 clade 2.1.3 product A was better than vaccine product B, and when chicken vaccinated against H5N1 clade 2.3.2, H5N1 clade 2.3.2 vaccine was the best to be used. In order to protect chicken from AI subtype H5N1 clade 2.1.3 and 2.3.2 in the field, a bivalent vaccine of H5N1 clade 2.1.3 and 2.3.2 subtypes should be developed.

  8. Protective efficacy of crude virus-like particle vaccine against HPAI H5N1 in chickens and its application on DIVA strategy.

    Science.gov (United States)

    Park, Jae-Keun; Lee, Dong-Hun; Youn, Ha-Na; Kim, Myeong-Seob; Lee, Yu-Na; Yuk, Seong-Su; Lim, Tae-Hyun; Jang, Jun-Hyuk; Kwon, Jung-Hoon; Kim, Byoung-Yoon; Kang, Sang-Moo; Seong, Baik-Lin; Lee, Joong-Bok; Park, Seung-Yong; Choi, In-Soo; Song, Chang-Seon

    2013-05-01

    Currently, Asian lineage highly pathogenic avian influenza (HPAI) H5N1 has become widespread across continents. These viruses are persistently circulating among poultry populations in endemic regions, causing huge economic losses, and raising concerns about an H5N1 pandemic. To control HPAI H5N1, effective vaccines for poultry are urgently needed. In this study, we developed HPAI virus-like particle (VLP) vaccine as a candidate poultry vaccine and evaluated its protective efficacy and possible application for differentiating infected from vaccinated animals (DIVA). Specific pathogen-free chickens received a single injection of HPAI H5N1 VLP vaccine generated using baculovirus expression vector system. Immunogenicity of VLP vaccines was determined using hemagglutination inhibition (HI), neuraminidase inhibition (NI), and ELISA test. Challenge study was performed to evaluate efficacy of VLP vaccines. A single immunization with HPAI H5N1 VLP vaccine induced high levels of HI and NI antibodies and protected chickens from a lethal challenge of wild-type HPAI H5N1 virus. Viral excretion from the vaccinated and challenged group was strongly reduced compared with a mock-vaccinated control group. Furthermore, we were able to differentiate VLP-vaccinated chickens from vaccinated and then infected chickens with a commercial ELISA test kit, which offers a promising strategy for the application of DIVA concept. © 2012 Blackwell Publishing Ltd.

  9. Avian influenza H5N1 virus infections in vaccinated commercial and backyard poultry in Egypt.

    Science.gov (United States)

    Hafez, M H; Arafa, A; Abdelwhab, E M; Selim, A; Khoulosy, S G; Hassan, M K; Aly, M M

    2010-08-01

    In this paper, we describe results from a high-pathogenic H5N1 avian influenza virus (AIV) surveillance program in previously H5-vaccinated commercial and family-backyard poultry flocks that was conducted from 2007 to 2008 by the Egyptian National Laboratory for Veterinary Quality Control on Poultry Production. The real-time reverse transcription PCR assay was used to detect the influenza A virus matrix gene and detection of the H5 and N1 subtypes was accomplished using a commercially available kit real-time reverse transcription PCR assay. The virus was detected in 35/3,610 (0.97%) and 27/8,682 (0.31%) of examined commercial poultry farms and 246/816 (30%) and 89/1,723 (5.2%) of backyard flocks in 2007 and 2008, respectively. Positive flocks were identified throughout the year, with the highest frequencies occurring during the winter months. Anti-H5 serum antibody titers in selected commercial poultry ranged from poultry in Egypt to combat H5N1 AIV, continuous circulation of the virus in vaccinated commercial and backyard poultry was reported and the efficacy of the vaccination using a challenge model with the current circulating field virus should be revised.

  10. Effect of viral membrane fusion activity on antibody induction by influenza H5N1 whole inactivated virus vaccine.

    Science.gov (United States)

    Geeraedts, Felix; ter Veer, Wouter; Wilschut, Jan; Huckriede, Anke; de Haan, Aalzen

    2012-10-05

    Whole inactivated virus (WIV) influenza vaccines are more immunogenic in unprimed individuals than split-virus or subunit vaccines. In mice, this superior immunogenicity has been linked to the recognition of the viral ssRNA by endosomal TLR7 receptors in immune cells, leading to IFNα production and Th1-type antibody responses. Recent data suggest that viral membrane fusion in target cell endosomes is necessary for TLR7-mediated IFNα induction. If so, virus inactivation procedures that compromise the fusion activity of WIV vaccines, like formaldehyde (FA) treatment, could potentially harm vaccine efficacy. Therefore, we measured the effect of fusion inactivation of H5N1 WIV on TLR7 activation in vitro, and on antibody isotype responses in vivo. Fusion inactivation of WIV reduced, but did not block, TLR7-dependent IFNα induction in murine dendritic cells in vitro. In vivo, fusion-inactive WIV was as potent as fusion-active WIV in inducing total H5N1-specific serum IgG and IgG2c subtype antibodies in unprimed mice. Both vaccines induced only small amounts of IgG1. However, FA treatment of WIV did reduce the capacity of the vaccine to induce hemagglutination-inhibiting (HI) antibodies. This possibly relates to modification of epitopes that are targets for HI antibodies rather than to loss of fusion activity. Antibody affinity maturation was not negatively affected by fusion inactivation. In conclusion, fusion activity of H5N1 WIV does not play a major role in Th1-type antibody induction. Yet, to preserve the full immunogenicity of WIV, or possibly also other inactivated influenza vaccines, harsh treatment with formaldehyde should be avoided. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Safety and immunogenicity of Sinovac’s prototype pandemic influenza H5N1 vaccines: a review on clinical trials

    OpenAIRE

    Qiu, Yuan‐Zheng; Yin, Wei‐Dong

    2008-01-01

    Abstract  Sinovac Biotech started to develop prototype pandemic influenza H5N1 vaccines in March 2004. On 2 April 2008, Sinovac’s inactivated, aluminium‐adjuvanted, whole‐virion prototype pandemic influenza A (H5N1) vaccine (PanFlu™) was granted production licensure by the China regulatory authority State Food and Drug Administration. The whole‐virion H5N1 vaccine was manufactured in embryonated hens’ eggs using the reassortant strain NIBRG‐14 (A/Vietnam/1194/2004‐A/PR/8/34) as vaccine virus....

  12. 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

  13. Avian influenza H5N1 vaccination efficacy in Egyptian backyard poultry.

    Science.gov (United States)

    Kandeil, Ahmed; Mostafa, Ahmed; El-Shesheny, Rabeh; El-Taweel, Ahmed Nageh; Gomaa, Mokhtar; Galal, Hussein; Kayali, Ghazi; Ali, Mohamed A

    2017-09-25

    Raising backyard poultry under low biosecurity conditions is a common practice in Egypt. While vaccination is routinely applied in Egypt in commercial settings to curb the spread of avian influenza viruses, it remains less commonly used in backyard settings. We assessed the immunogenicity and protective efficacy of a H5N1 vaccine based on a contemporary Egyptian clade 2.2.1.2 virus among turkeys, ducks, geese, and chickens raised together in a backyard setting. Results showed that this vaccine elicits an immune response in all tested species reaching up to a hemagglutination inhibition titer of 10 log2 after a booster dose. However, this response varied between species. When challenged, vaccinated birds survived and shed less virus in comparison with unvaccinated birds. However, unvaccinated ducks showed no symptoms of infection and survived the duration of the experiment. Moreover, vaccinated ducks shed more virus as compared to vaccinated birds of other species. Hence, we recommend avoiding mixing various species in the backyards of Egypt. Our data indicates that vaccination can be effective in the backyard setting in Egypt, although planning should consider the species covered. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Vaccine Design for H5N1 Based on B- and T-cell Epitope Predictions.

    Science.gov (United States)

    Tambunan, Usman Sumo Friend; Sipahutar, Feimmy Ruth Pratiwi; Parikesit, Arli Aditya; Kerami, Djati

    2016-01-01

    From 2003 to 2013, Indonesia had the highest number of avian influenza A cases in humans, with 192 cases and 160 fatalities. Avian influenza is caused by influenza virus type A, such as subtype H5N1. This virus has two glycoproteins: hemagglutinin and neuraminidase, which will become the primary target to be neutralized by vaccine. Vaccine is the most effective immunologic intervention. In this study, we use the epitope-based vaccine design from hemagglutinin and neuraminidase of H5N1 Indonesian strain virus by using immunoinformatics approach in order to predict the binding of B-cell and T-cell epitopes (class I and class II human leukocyte antigen [HLA]). BCPREDS was used to predict the B-cell epitope. Propred, Propred I, netMHCpan, and netMHCIIpan were used to predict the T-cell epitope. Two B-cell epitopes of hemagglutinin candidates and one B-cell epitope of neuraminidase candidates were obtained to bind T-cell CD4(+) (class II HLA), and also five T-cell epitope hemagglutinin and four T-cell epitope neuraminidase were obtained to bind T-cell CD8(+) (class I HLA). The visualization of epitopes was done using MOE 2008.10. It shows that the binding affinity of epitope-HLA was based on minimum binding free energy (ΔG binding). Based on this result, visualization, and dynamic simulation, four hemagglutinin epitopes (MEKIVLLLA, CPYLGSPSF, KCQTPMGAI, and IGTSTLNQR) and two neuraminidase epitopes (NPNQKIITI and CYPDAGEIT) were computed as having the best binding affinity from HLA ligand. The results mentioned above are from in silico experiments and need to be validated using wet experiment.

  15. Evaluation of the protection induced by avian influenza vaccines containing a 1994 Mexican H5N2 LPAI seed strain against a 2008 Egyptian H5N1 HPAI virus belonging to clade 2.2.1 by means of serological and in vivo tests.

    Science.gov (United States)

    Terregino, Calogero; Toffan, Anna; Cilloni, Filippo; Monne, Isabella; Bertoli, Elena; Castellanos, Lilia; Amarin, Nadim; Mancin, Marzia; Capua, Ilaria

    2010-06-01

    Since 2006 Egypt has been facing an extensive epidemic of H5N1 highly pathogenic avian influenza (HPAI) with a huge number of outbreaks both in rural and intensively reared poultry areas. The use of efficacious vaccines in this country has been, and still remains, essential for the control and possible eradication of HPAI. The present study was performed to establish whether the administration of inactivated vaccines containing an H5 virus belonging to a different lineage to the Eurasian H5N1 HPAI viruses guarantees protection from clinical signs, provides significant immune response and is able to achieve a reduction of viral shedding in the face of a challenge with a contemporary H5N1 virus isolated in Egypt. Despite the genetic and antigenic differences between the vaccine strain (H5N2/Mexico) and the challenge strain (H5N1/Egypt), confirmed by molecular and serological (haemagglutination inhibition) tests, it was established that the immune response induced by these conventional vaccines is sufficient to prevent infection in the majority of birds challenged with a contemporary H5N1 Egyptian strain. The data reported in this study also indicate that there may be a low degree of correlation between haemagglutination inhibition titres, clinical protection and reduction of shedding.

  16. 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.

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

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    Amorsolo L Suguitan

    2006-09-01

    Full Text Available 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 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. 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.

  18. H5N1 Avian Influenza Pre-pandemic Vaccine Strains in China

    Institute of Scientific and Technical Information of China (English)

    BO Hong; DONG Li Bo; ZHANG Ye; DONG Jie; ZOU Shu Mei; GAO Rong Bao; WANG Da Yan; SHU Yue Long

    2014-01-01

    ObjectiveTo prepare the 4 candidate vaccine strains of H5N1 avian influenza virus isolated in China. MethodsRecombinant viruses were rescued using reverse genetics. Neuraminidase (NA) and hemagglutinin (HA) segments of the A/Xinjiang/1/2006, A/Guangxi/1/2009, A/Hubei/1/2010, and A/Guangdong/1/2011 viruses were amplified by RT-PCR. Multibasic amino acid cleavage site of HA was removed and ligated into the pCIpolI vector for virus rescue. The recombinant viruses were evaluated by trypsin dependent assays. Their embryonate survival and antigenicity were compared with those of the respective wild-type viruses. ResultsThe 4 recombinant viruses showed similar antigenicity compared with wild-type viruses, chickenembryo survival and trypsin-dependent characteristics. ConclusionThe 4 recombinantviruses rescued using reverse genetics meet the criteria for classification of low pathogenic avian influenza strains, thus supporting the use of them for the development of seeds and production of pre-pandemic vaccines.

  19. Predicted epitopes of H5N1 bird flu virus by bioinformatics method: a clue for further vaccine development

    Institute of Scientific and Technical Information of China (English)

    Viroj Wiwnanitkit

    2006-01-01

    @@ To the Editor: Bird flu or avian flu, caused by H5N1 virus, is a new emerging infectious disease. It is noted that this H5N1 virus jumped the species barrier and caused severe disease with high mortality in humans in many countries. The continued westward dissemination of H5N1 influenza A viruses in avian populations and the nearly 50% mortality of humans infected with H5N1 are a source of great international concern.1Providing sufficient antiviral drugs and development and approval of new vaccines are the keys for control of the possible emerging pandemic of this atypical influenza.1,2 Based on the advance in bioinformatics, the immunomics becomes a new alternative in vaccine development.3

  20. An H5N1 M2e-based multiple antigenic peptide vaccine confers heterosubtypic protection from lethal infection with pandemic 2009 H1N1 virus

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    Yu Hong

    2010-07-01

    Full Text Available Abstract Background A 2009 global influenza pandemic caused by a novel swine-origin H1N1 influenza A virus has posted an increasing threat of a potential pandemic by the highly pathogenic avian influenza (HPAI H5N1 virus, driving us to develop an influenza vaccine which confers cross-protection against both H5N1 and H1N1 viruses. Previously, we have shown that a tetra-branched multiple antigenic peptide (MAP vaccine based on the extracellular domain of M2 protein (M2e from H5N1 virus (H5N1-M2e-MAP induced strong immune responses and cross-protection against different clades of HPAI H5N1 viruses. In this report, we investigated whether such M2e-MAP presenting the H5N1-M2e consensus sequence can afford heterosubtypic protection from lethal challenge with the pandemic 2009 H1N1 virus. Results Our results demonstrated that H5N1-M2e-MAP plus Freund's or aluminum adjuvant induced strong cross-reactive IgG antibody responses against M2e of the pandemic H1N1 virus which contains one amino acid variation with M2e of H5N1 at position 13. These cross-reactive antibodies may maintain for 6 months and bounced back quickly to the previous high level after the 2nd boost administered 2 weeks before virus challenge. H5N1-M2e-MAP could afford heterosubtypic protection against lethal challenge with pandemic H1N1 virus, showing significant decrease of viral replications and obvious alleviation of histopathological damages in the challenged mouse lungs. 100% and 80% of the H5N1-M2e-MAP-vaccinated mice with Freund's and aluminum adjuvant, respectively, survived the lethal challenge with pandemic H1N1 virus. Conclusions Our results suggest that H5N1-M2e-MAP has a great potential to prevent the threat from re-emergence of pandemic H1N1 influenza and possible novel influenza pandemic due to the reassortment of HPAI H5N1 virus with the 2009 swine-origin H1N1 influenza virus.

  1. 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 BACKGROUND: 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. METHODOLOGY / PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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.

  2. Proinflammatory cytokine responses induced by influenza A (H5N1 viruses in primary human alveolar and bronchial epithelial cells

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    Poon LLM

    2005-11-01

    Full Text Available Abstract Background Fatal human respiratory disease associated with influenza A subtype H5N1 has been documented in Hong Kong, and more recently in Vietnam, Thailand and Cambodia. We previously demonstrated that patients with H5N1 disease had unusually high serum levels of IP-10 (interferon-gamma-inducible protein-10. Furthermore, when compared with human influenza virus subtype H1N1, the H5N1 viruses in 1997 (A/Hong Kong/483/97 (H5N1/97 were more potent inducers of pro-inflammatory cytokines (e.g. tumor necrosis factor-a and chemokines (e.g. IP-10 from primary human macrophages in vitro, which suggests that cytokines dysregulation may play a role in pathogenesis of H5N1 disease. Since respiratory epithelial cells are the primary target cell for replication of influenza viruses, it is pertinent to investigate the cytokine induction profile of H5N1 viruses in these cells. Methods We used quantitative RT-PCR and ELISA to compare the profile of cytokine and chemokine gene expression induced by H5N1 viruses A/HK/483/97 (H5N1/97, A/Vietnam/1194/04 and A/Vietnam/3046/04 (both H5N1/04 with that of human H1N1 virus in human primary alveolar and bronchial epithelial cells in vitro. Results We demonstrated that in comparison to human H1N1 viruses, H5N1/97 and H5N1/04 viruses were more potent inducers of IP-10, interferon beta, RANTES (regulated on activation, normal T cell expressed and secreted and interleukin 6 (IL-6 in primary human alveolar and bronchial epithelial cells in vitro. Recent H5N1 viruses from Vietnam (H5N1/04 appeared to be even more potent at inducing IP-10 than H5N1/97 virus. Conclusion The H5N1/97 and H5N1/04 subtype influenza A viruses are more potent inducers of proinflammatory cytokines and chemokines in primary human respiratory epithelial cells than subtype H1N1 virus. We suggest that this hyper-induction of cytokines may be relevant to the pathogenesis of human H5N1 disease.

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

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    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.

  4. Intranasal H5N1 vaccines, adjuvanted with chitosan derivatives, protect ferrets against highly pathogenic influenza intranasal and intratracheal challenge

    NARCIS (Netherlands)

    A.J. Mann (Alex); N. Noulin (Nicolas); A. Catchpole (Andrew); K.J. Stittelaar (Koert); L. de Waal (Leon); E.J.B. Veldhuis Kroeze (Edwin); M. Hinchcliffe (Michael); A. Smith (Alan); E. Montomoli (Emanuele); S. Piccirella (Simona); A.D.M.E. Osterhaus (Albert); A. Knight (Alastair); J. Oxford; G. Lapini (Giulia); R. Cox (Ruben); R. Lambkin-Williams (Rob)

    2014-01-01

    textabstractWe investigated the protective efficacy of two intranasal chitosan (CSN and TM-CSN) adjuvanted H5N1 Influenza vaccines against highly pathogenic avian Influenza (HPAI) intratracheal and intranasal challenge in a ferret model. Six groups of 6 ferrets were intranasally vaccinated twice, 21

  5. Improving pandemic H5N1 influenza vaccines by combining different vaccine platforms.

    Science.gov (United States)

    Luke, Catherine J; Subbarao, Kanta

    2014-07-01

    A variety of platforms are being explored for the development of vaccines for pandemic influenza. Observations that traditional inactivated subvirion vaccines and live-attenuated vaccines against H5 and some H7 influenza viruses were poorly immunogenic spurred efforts to evaluate new approaches, including whole virus vaccines, higher doses of antigen, addition of adjuvants and combinations of different vaccine modalities in heterologous prime-boost regimens to potentiate immune responses. Results from clinical trials of prime-boost regimens have been very promising. Further studies are needed to determine optimal combinations of platforms, intervals between doses of vaccines and the logistics of deployment in pre-pandemic and early pandemic settings.

  6. Cell-Based Systems Biology Analysis of Human AS03-Adjuvanted H5N1 Avian Influenza Vaccine Responses: A Phase I Randomized Controlled Trial

    Science.gov (United States)

    Samir, Parimal; Galassie, Allison; Allos, Tara M.; Niu, Xinnan; Gordy, Laura E.; Creech, C. Buddy; Prasad, Nripesh; Jensen, Travis L.; Hill, Heather; Levy, Shawn E.; Joyce, Sebastian; Link, Andrew J.; Edwards, Kathryn M.

    2017-01-01

    Background Vaccine development for influenza A/H5N1 is an important public health priority, but H5N1 vaccines are less immunogenic than seasonal influenza vaccines. Adjuvant System 03 (AS03) markedly enhances immune responses to H5N1 vaccine antigens, but the underlying molecular mechanisms are incompletely understood. Objective and Methods We compared the safety (primary endpoint), immunogenicity (secondary), gene expression (tertiary) and cytokine responses (exploratory) between AS03-adjuvanted and unadjuvanted inactivated split-virus H5N1 influenza vaccines. In a double-blinded clinical trial, we randomized twenty adults aged 18–49 to receive two doses of either AS03-adjuvanted (n = 10) or unadjuvanted (n = 10) H5N1 vaccine 28 days apart. We used a systems biology approach to characterize and correlate changes in serum cytokines, antibody titers, and gene expression levels in six immune cell types at 1, 3, 7, and 28 days after the first vaccination. Results Both vaccines were well-tolerated. Nine of 10 subjects in the adjuvanted group and 0/10 in the unadjuvanted group exhibited seroprotection (hemagglutination inhibition antibody titer > 1:40) at day 56. Within 24 hours of AS03-adjuvanted vaccination, increased serum levels of IL-6 and IP-10 were noted. Interferon signaling and antigen processing and presentation-related gene responses were induced in dendritic cells, monocytes, and neutrophils. Upregulation of MHC class II antigen presentation-related genes was seen in neutrophils. Three days after AS03-adjuvanted vaccine, upregulation of genes involved in cell cycle and division was detected in NK cells and correlated with serum levels of IP-10. Early upregulation of interferon signaling-related genes was also found to predict seroprotection 56 days after first vaccination. Conclusions Using this cell-based systems approach, novel mechanisms of action for AS03-adjuvanted pandemic influenza vaccination were observed. Trial Registration ClinicalTrials.gov NCT

  7. Determination of efficacious vaccine seed strains for use against Egyptian H5N1 highly pathogenic avian influenza viruses through antigenic cartography and in vivo challenge studies

    Science.gov (United States)

    Since 2006, there have been reported outbreaks of H5N1 highly pathogenic avian influenza (HPAI) in vaccinated chickens in Africa and Asia. This study provides experimental data for selection of efficacious H5N1 vaccine seed strains against recently circulating strains of H5N1 HPAI viruses in Egypt....

  8. Vectors based on modified vaccinia Ankara expressing influenza H5N1 hemagglutinin induce substantial cross-clade protective immunity.

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    Annett Hessel

    Full Text Available BACKGROUND: New highly pathogenic H5N1 influenza viruses are continuing to evolve with a potential threat for an influenza pandemic. So far, the H5N1 influenza viruses have not widely circulated in humans and therefore constitute a high risk for the non immune population. The aim of this study was to evaluate the cross-protective potential of the hemagglutinins of five H5N1 strains of divergent clades using a live attenuated modified vaccinia Ankara (MVA vector vaccine. METHODOLOGY/PRINCIPAL FINDINGS: The replication-deficient MVA virus was used to express influenza hemagglutinin (HA proteins. Specifically, recombinant MVA viruses expressing the HA genes of the clade 1 virus A/Vietnam/1203/2004 (VN/1203, the clade 2.1.3 virus A/Indonesia/5/2005 (IN5/05, the clade 2.2 viruses A/turkey/Turkey/1/2005 (TT01/05 and A/chicken/Egypt/3/2006 (CE/06, and the clade 2.3.4 virus A/Anhui/1/2005 (AH1/05 were constructed. These experimental live vaccines were assessed in a lethal mouse model. Mice vaccinated with the VN/1203 hemagglutinin-expressing MVA induced excellent protection against all the above mentioned clades. Also mice vaccinated with the IN5/05 HA expressing MVA induced substantial protection against homologous and heterologous AH1/05 challenge. After vaccination with the CE/06 HA expressing MVA, mice were fully protected against clade 2.2 challenge and partially protected against challenge of other clades. Mice vaccinated with AH1/05 HA expressing MVA vectors were only partially protected against homologous and heterologous challenge. The live vaccines induced substantial amounts of neutralizing antibodies, mainly directed against the homologous challenge virus, and high levels of HA-specific IFN-γ secreting CD4 and CD8 T-cells against epitopes conserved among the H5 clades and subclades. CONCLUSIONS/SIGNIFICANCE: The highest level of cross-protection was induced by the HA derived from the VN/1203 strain, suggesting that pandemic H5 vaccines

  9. Maternal immunity against avian influenza H5N1 in chickens: limited protection and interference with vaccine efficacy

    NARCIS (Netherlands)

    Maas, H.A.; Rosema, S.; Zoelen-Bos, van D.J.; Kemper-Venema, S.

    2011-01-01

    After avian influenza (AI) vaccination, hens will produce progeny chickens with maternally derived AI-specific antibodies. In the present study we examined the effect of maternal immunity in young chickens on the protection against highly pathogenic AI H5N1 virus infection and on the effectiveness o

  10. Vaccination of gallinaceous poultry for H5N1 highly pathogenic avian influenza: current questions and new technology.

    Science.gov (United States)

    Spackman, Erica; Swayne, David E

    2013-12-05

    Vaccination of poultry for avian influenza virus (AIV) is a complex topic as there are numerous technical, logistic and regulatory aspects which must be considered. Historically, control of high pathogenicity (HP) AIV infection in poultry has been accomplished by eradication and stamping out when outbreaks occur locally. Since the H5N1 HPAIV from Asia has spread and become enzootic, vaccination has been used on a long-term basis by some countries to control the virus, other countries have used it temporarily to aid eradication efforts, while others have not used it at all. Currently, H5N1 HPAIV is considered enzootic in China, Egypt, Viet Nam, India, Bangladesh and Indonesia. All but Bangladesh and India have instituted vaccination programs for poultry. Importantly, the specifics of these programs differ to accommodate different situations, resources, and industry structure in each country. The current vaccines most commonly used are inactivated whole virus vaccines, but vectored vaccine use is increasing. Numerous technical improvements to these platforms and novel vaccine platforms for H5N1 vaccines have been reported, but most are not ready to be implemented in the field.

  11. Vaccination with Astragalus and Ginseng Polysaccharides Improves Immune Response of Chickens against H5N1 Avian Influenza Virus

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    Auwalu Yusuf Abdullahi

    2016-01-01

    Full Text Available To determine the effect of astragalus and ginseng polysaccharides (APS, GPS on immune response and improvement of H5N1 vaccine, 360-day-old broilers were randomly divided into 8 groups of 45 chicks, comprising APS groups (1–3; GPS groups (4–6; vaccine group (7; and blank control (8 (without polysaccharide and vaccine. From day 12 after hatch groups 1–3 were given APS and groups 4–6 with GPS both at 100, 200, and 400 (mg/kg, respectively. At day 15 after hatch, groups 1–7 were vaccinated with 0.3 mL H5N1 vaccine subcutaneously; daily weight gain (DWG and serum Ig antibody (by HI-test were measured on 3, 7, 14, and 28 days after vaccination. Serum antibody titers and expression of cytokines (IL-2, IL-10, I FN-γ, and TNF were determined by ELISA and RT-PCR. Results revealed that all the polysaccharide groups were numerically increased in antibody levels and the expression of cytokines was significant (P<0.05 in the APS and GPS groups compared to corresponding vaccine group and blank control. DWG was higher (P<0.05 in 400 mg/kg APS groups than control groups. Thus oral supplements of GPS and APS have shown their potential in the improvement of immune response and could be used as adjuvant in a formulation of H5N1 vaccine.

  12. 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.

  13. Progress in Research on Pandemic Influenza H5N1 Vaccine%H5N1大流行流感疫苗的研究进展

    Institute of Scientific and Technical Information of China (English)

    张严予

    2011-01-01

    Highly pathogenic avian influenza H5N1 virus may cause serious fatal diseases and constitute a grave threat to human health. Although the current H5N1 influenza strains appear not to be transmissible from human to human, it is of major concern that mixing with human influenza strains could convert H5N1 to a strain that would spread that would spread from human to human and cause a serious pandemic. In addition, avian influenza H5N1 virus after continuous variation may break through the species barrier and spread to mammals and humans, thereby cause disease even death under the influence of various virus and host factors. This paper reviews the progress in research on pandemic influenza vaccine.%高致病性H5N1流感病毒可导致严重的致死性疾病,对人类健康造成了极大威胁.尽管目前尚未发生人与人之间传播,但该病毒一旦与人流感病毒重组,即有可能转变为可在人与人之间传播的高致死性流感病毒,从而导致新的流感大流行.此外,H5N1流感病毒经过不断变异后可突破种属屏障,从禽类传播给哺乳动物及人类,并进一步在病毒和宿主的多种因素作用下导致宿主发病乃至死亡.本文对H5N1大流行流感疫苗的研究进展作一综述.

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

    NARCIS (Netherlands)

    J.H.C.M. Kreijtz (Joost); Y. Suezer; G. de Mutsert (Gerrie); G. van Amerongen (Geert); A. Scwantes (Astrid); J.M.A. van den Brand (Judith); R.A.M. Fouchier (Ron); J. Löwer; A.D.M.E. Osterhaus (Albert); G. Sutter (Gerd); G.F. Rimmelzwaan (Guus)

    2009-01-01

    textabstractHuman 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

  15. Vaccination with virus-like particles containing H5 antigens from three H5N1 clades protects chickens from H5N1 and H5N8 influenza viruses

    Science.gov (United States)

    Highly pathogenic avian influenza (HPAI) viruses, especially H5N1 strains, represent a public health threat and cause widespread morbidity and mortality in domestic poultry. Recombinant virus-like particles (VLPs) represent a promising novel vaccine approach to control avian influenza including HPAI...

  16. Preparation and immune activity analysis of H5N1 subtype avian influenza virus recombinant protein-based vaccine.

    Science.gov (United States)

    Xie, Q M; Ji, J; Du, L Q; Cao, Y C; Wei, L; Xue, C Y; Qin, J P; Ma, J Y; Bi, Y Z

    2009-08-01

    Avian influenza is a severe disease among farmed poultry and free-living birds and a constant threat to the commercial chicken industry around the world. Hemagglutinin (HA) is the major immunogen on the envelope of influenza A virus and is the predominant inducer of neutralizing antibody. To obtain the bioactive antigen proteins in large quantities, a new protein expression vector pBCX was constructed, which is based on the pET32a vector. The HA gene of the H5N1 subtype of avian influenza virus (AIV) was inserted into the pBCX vector and expressed efficiently in Escherichia coli BL21 (DE3). Fused expression of the exogenous gene and msyB produced a 97-kDa msyB-HA fusion protein. Sodium dodecyl sulfate-PAGE combined with scanning analysis demonstrated that the msyB-HA fusion protein accounted for 29.5% of the total bacterial protein, 90.5% being soluble. The msyB-HA fusion protein was purified with nondenaturing 50% Ni-NTA column chromatography, and the result showed that 24 mg of purified msyB-HA fusion protein could be obtained from 1 L of induced expression bacterial culture medium. The comparative results in the present study showed that pBCX was superior to pET32a as a protein expression vector. Western blotting showed the recombinant msyB-HA (rHA) to have better antigenic activity, which may be the result from the better posttranslation protein modification and folding in the pBCX expression system. With the rHA fusion protein as antigen, we successfully prepared and screened specific monoclonal antibodys against the H5N1 subtype AIV, which indicated that the rHA had antigen epitopes and biofunctions. The immune test confirmed that the rHA protein vaccine could also induce high neutralizing antibodies, and the AIV challenge test proved that the rHA protein-based vaccine could prevent the corresponding infection. This study demonstrates that the recombinant HA protein produced by the pBCX expression system could be used as a recombinant protein-based vaccine

  17. Genetic and antigenic analysis of H5N1 viruses for selection of HA-donor virus for vaccine strains.

    Science.gov (United States)

    Bhatia, S; Kunal, A; Khandia, R; Siddiqui, A; Pateriya, A K; Sood, R

    2013-12-01

    Genetic and antigenic analysis of H5N1 viruses, isolated in India during a period from year 2006 to 2010, was carried out for selection of the potential H5-HA (haemagglutinin) gene donor virus for developing a reverse genetics based DIVA marker H5 vaccine for poultry in India. Out of the 47 H5N1 viruses (clade 2.2), 14 representative viruses were selected on the basis of amino acid sequence analysis of HA1 gene for further antigenic characterization. Using antigenic cartography, an antigenic map was constructed based on the data of cross-HI (haemagglutinin inhibition) titration of 14 sera versus 14 viruses to visualize the relatedness among the antigens and antigenic coverage of the sera. Sera against five H5N1 viruses (A/crow/Assam/142119/2008, A/chicken/West Bengal/100879/2008, A/chicken/West Bengal/155505/2009, A/chicken/West Bengal/80995/2008 and A/chicken/West Bengal/81760/2008) exhibited maximum (100 %) antigenic coverage, hence, were selected as the potential HA donor viruses. However, the virus strain A/chicken/West Bengal/80995/2008 matched completely with the consensus amino acid sequence of the 47 viruses, therefore, was considered the best HA donor candidate out of the five showing 100 % antigenic coverage. The present study demonstrates a stepwise methodology for logical selection of vaccine strain or HA gene donor strain for developing H5 vaccines using genetic and antigenic data.

  18. Preclinical and clinical development of plant-made virus-like particle vaccine against avian H5N1 influenza.

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    Nathalie Landry

    Full Text Available UNLABELLED: The recent swine H1N1 influenza outbreak demonstrated that egg-based vaccine manufacturing has an Achille's heel: its inability to provide a large number of doses quickly. Using a novel manufacturing platform based on transient expression of influenza surface glycoproteins in Nicotiana benthamiana, we have recently demonstrated that a candidate Virus-Like Particle (VLP vaccine can be generated within 3 weeks of release of sequence information. Herein we report that alum-adjuvanted plant-made VLPs containing the hemagglutinin (HA protein of H5N1 influenza (A/Indonesia/5/05 can induce cross-reactive antibodies in ferrets. Even low doses of this vaccine prevented pathology and reduced viral loads following heterotypic lethal challenge. We further report on safety and immunogenicity from a Phase I clinical study of the plant-made H5 VLP vaccine in healthy adults 18-60 years of age who received 2 doses 21 days apart of 5, 10 or 20 µg of alum-adjuvanted H5 VLP vaccine or placebo (alum. The vaccine was well tolerated at all doses. Adverse events (AE were mild-to-moderate and self-limited. Pain at the injection site was the most frequent AE, reported in 70% of vaccinated subjects versus 50% of the placebo recipients. No allergic reactions were reported and the plant-made vaccine did not significantly increase the level of naturally occurring serum antibodies to plant-specific sugar moieties. The immunogenicity of the H5 VLP vaccine was evaluated by Hemagglutination-Inhibition (HI, Single Radial Hemolysis (SRH and MicroNeutralisation (MN. Results from these three assays were highly correlated and showed similar trends across doses. There was a clear dose-response in all measures of immunogenicity and almost 96% of those in the higher dose groups (2 × 10 or 20 µg mounted detectable MN responses. Evidence of striking cross-protection in ferrets combined with a good safety profile and promising immunogenicity in humans suggest that plant

  19. Preclinical and clinical development of plant-made virus-like particle vaccine against avian H5N1 influenza.

    Science.gov (United States)

    Landry, Nathalie; Ward, Brian J; Trépanier, Sonia; Montomoli, Emanuele; Dargis, Michèle; Lapini, Giulia; Vézina, Louis-P

    2010-12-22

    The recent swine H1N1 influenza outbreak demonstrated that egg-based vaccine manufacturing has an Achille's heel: its inability to provide a large number of doses quickly. Using a novel manufacturing platform based on transient expression of influenza surface glycoproteins in Nicotiana benthamiana, we have recently demonstrated that a candidate Virus-Like Particle (VLP) vaccine can be generated within 3 weeks of release of sequence information. Herein we report that alum-adjuvanted plant-made VLPs containing the hemagglutinin (HA) protein of H5N1 influenza (A/Indonesia/5/05) can induce cross-reactive antibodies in ferrets. Even low doses of this vaccine prevented pathology and reduced viral loads following heterotypic lethal challenge. We further report on safety and immunogenicity from a Phase I clinical study of the plant-made H5 VLP vaccine in healthy adults 18-60 years of age who received 2 doses 21 days apart of 5, 10 or 20 µg of alum-adjuvanted H5 VLP vaccine or placebo (alum). The vaccine was well tolerated at all doses. Adverse events (AE) were mild-to-moderate and self-limited. Pain at the injection site was the most frequent AE, reported in 70% of vaccinated subjects versus 50% of the placebo recipients. No allergic reactions were reported and the plant-made vaccine did not significantly increase the level of naturally occurring serum antibodies to plant-specific sugar moieties. The immunogenicity of the H5 VLP vaccine was evaluated by Hemagglutination-Inhibition (HI), Single Radial Hemolysis (SRH) and MicroNeutralisation (MN). Results from these three assays were highly correlated and showed similar trends across doses. There was a clear dose-response in all measures of immunogenicity and almost 96% of those in the higher dose groups (2 × 10 or 20 µg) mounted detectable MN responses. Evidence of striking cross-protection in ferrets combined with a good safety profile and promising immunogenicity in humans suggest that plant-based VLP vaccines should

  20. 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, E-mail: euy-tokyo@umin.ac.jp [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, E-mail: liaogy@21cn.com [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.

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

    Science.gov (United States)

    Halbherr, Stefan J; Brostoff, Terza; Tippenhauer, Merve; Locher, Samira; Berger Rentsch, Marianne; Zimmer, Gert

    2013-01-01

    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.

  2. 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.

  3. A single vaccination of commercial broilers does not reduce transmission of H5N1 highly pathogenic avian influenza

    Directory of Open Access Journals (Sweden)

    Poetri Okti

    2011-06-01

    Full Text Available Abstract Vaccination of chickens has become routine practice in Asian countries in which H5N1 highly pathogenic avian influenza (HPAI is endemically present. This mainly applies to layer and breeder flocks, but broilers are usually left unvaccinated. Here we investigate whether vaccination is able to reduce HPAI H5N1 virus transmission among broiler chickens. Four sets of experiments were carried out, each consisting of 22 replicate trials containing a pair of birds. Experiments 1-3 were carried out with four-week-old birds that were unvaccinated, and vaccinated at day 1 or at day 10 of age. Experiment 4 was carried out with unvaccinated day-old broiler chicks. One chicken in each trial was inoculated with H5N1 HPAI virus. One chicken in each trial was inoculated with virus. The course of the infection chain was monitored by serological analysis, and by virus isolation performed on tracheal and cloacal swabs. The analyses were based on a stochastic SEIR model using a Bayesian inferential framework. When inoculation was carried out at the 28th day of life, transmission was efficient in unvaccinated birds, and in birds vaccinated at first or tenth day of life. In these experiments estimates of the latent period (~1.0 day, infectious period (~3.3 days, and transmission rate parameter (~1.4 per day were similar, as were estimates of the reproduction number (~4 and generation interval (~1.4 day. Transmission was significantly less efficient in unvaccinated chickens when inoculation was carried out on the first day of life. These results show that vaccination of broiler chickens does not reduce transmission, and suggest that this may be due to the interference of maternal immunity.

  4. Chronic Heat Stress Inhibits Immune Responses to H5N1 Vaccination through Regulating CD4+CD25+Foxp3+ Tregs

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    Di Meng

    2013-01-01

    Full Text Available Chronic heat stress (CHS is known to have negative impacts on the immune responses in animals and increases their susceptibility to infections including the highly pathogenic avian influenza virus H5N1. However, the role of regulatory T cells (Tregs in CHS immunosuppression remains largely undefined. In this study, we demonstrated a novel mechanism by which CHS suppressed both Th1 and Th2 immune responses and dramatically decreased the protective efficacy of the formalin-inactivated H5N1 vaccine against H5N1 influenza virus infection. This suppression was found to be associated with the induced generation of CD4+CD25+FoxP3+ Tregs and the increased secretions of IL-10 and TGF-β in CD4+ T cells. Adoptive transfer of the induced Tregs also suppressed the protective efficacy of formalin-inactivated H5N1 virus immunization. Collectively, this study identifies a novel mechanism of CHS immunosuppression mediated by regulating CD4+CD25+Foxp3+ Tregs.

  5. A computationally optimized broadly reactive H5 hemagglutinin vaccine provides protection against homologous and heterologous H5N1 highly pathogenic avian influenza virus infection in chickens

    Science.gov (United States)

    Since its emergence in 1996 in China, H5N1 highly pathogenic avian influenza (HPAI) virus has continuously evolved into different genetic clades that have created challenges to maintaining antigenically relevant H5N1 vaccine seeds. Therefore, a universal (multi-hemagglutinin [HA] subtype) or more c...

  6. Modelling influenza A H5N1 vaccination strategy scenarios in the household poultry sector in Egypt.

    Science.gov (United States)

    El Masry, Ihab; Rijks, Jolianne; Peyre, Marisa; Taylor, Nick; Lubroth, Juan; Jobre, Yilma

    2014-01-01

    Highly pathogenic avian influenza (AI) due to H5N1 virus was first reported in Egypt in February 2006; since then, the government has allowed avian influenza vaccination in poultry. The present study evaluated the impact of AI vaccination in terms of cumulative annual flock immunity (CAFI): the percentage of bird × weeks protected by immunity. This evaluation took account of the combined effects of vaccination coverage, vaccine efficacy (VE), and different characteristics of household poultry production on the effectiveness of the adopted vaccination strategy (VS), and provided alternative options for improvement. The evaluation used a population and vaccination model that calculates the CAFI. Participatory approaches were employed in 21 villages to develop the vaccination and flock parameters required for the model. The adopted VS were compared in the model with three alternative VS scenarios in terms of the CAFI. Vaccination coverage varied among villages but was generally low (between 1 and 48 %; median 14 %). Under the adopted VS, the CAFI predicted for the villages ranged from 2 to 31 %. It was concluded that despite the enormous effort put into rural household poultry AI vaccination by the Egyptian government, village CAFI is unlikely to be maintained at the levels required to significantly reduce the virus load and restrict transmission. In HPAI-endemic countries that consider AI vaccination as one of the disease control options, the high cost of mass AI vaccination campaigns and their achievable benefits must be compared with other available control measures, which may include targeted vaccination. Achievable vaccination coverage, VE and the different characteristics of commercial and household (village) poultry production are key parameters determining the feasibility and cost-effectiveness of different AI vaccination strategies.

  7. Vaccination with virus-like particles containing H5 antigens from three H5N1 clades protects chickens from H5N1 and H5N8 influenza viruses.

    Science.gov (United States)

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

    2016-03-18

    Highly pathogenic avian influenza (HPAI) viruses, especially H5N1 strains, represent a public health threat and cause widespread morbidity and mortality in domestic poultry. Recombinant virus-like particles (VLPs) represent a promising novel vaccine approach to control avian influenza including HPAI strains. Influenza VLPs contain viral hemagglutinin (HA), which can be expressed in cell culture within highly immunogenic VLPs that morphologically and antigenically resemble influenza virions, except VLPs are non-infectious. Here we describe a recombinant VLP containing HA proteins derived from three distinct clades of H5N1 viruses as an experimental, broadly protective H5 avian influenza vaccine. A baculovirus vector was configured to co-express the H5 genes from recent H5N1 HPAI isolates A/chicken/Germany/2014 (clade 2.3.4.4), A/chicken/West Java/Subang/29/2007 (clade 2.1.3) and A/chicken/Egypt/121/2012 (clade 2.2.1). Co-expression of these genes in Sf9 cells along with influenza neuraminidase (NA) and retrovirus gag genes resulted in production of triple-clade H555 VLPs that exhibited hemagglutination activity and morphologically resembled influenza virions. Vaccination of chickens with these VLPs resulted in induction of serum antibody responses and efficient protection against experimental challenges with three different viruses including the recent U.S. H5N8 HPAI isolate. We conclude that these novel triple-clade VLPs represent a feasible strategy for simultaneously evoking protective antibodies against multiple variants of H5 influenza virus.

  8. Superior immunogenicity of inactivated whole virus H5N1 influenza vaccine is primarily controlled by Toll-like receptor signalling.

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    Felix Geeraedts

    Full Text Available In the case of an influenza pandemic, the current global influenza vaccine production capacity will be unable to meet the demand for billions of vaccine doses. The ongoing threat of an H5N1 pandemic therefore urges the development of highly immunogenic, dose-sparing vaccine formulations. In unprimed individuals, inactivated whole virus (WIV vaccines are more immunogenic and induce protective antibody responses at a lower antigen dose than other formulations like split virus (SV or subunit (SU vaccines. The reason for this discrepancy in immunogenicity is a long-standing enigma. Here, we show that stimulation of Toll-like receptors (TLRs of the innate immune system, in particular stimulation of TLR7, by H5N1 WIV vaccine is the prime determinant of the greater magnitude and Th1 polarization of the WIV-induced immune response, as compared to SV- or SU-induced responses. This TLR dependency largely explains the relative loss of immunogenicity in SV and SU vaccines. The natural pathogen-associated molecular pattern (PAMP recognized by TLR7 is viral genomic ssRNA. Processing of whole virus particles into SV or SU vaccines destroys the integrity of the viral particle and leaves the viral RNA prone to degradation or involves its active removal. Our results show for a classic vaccine that the acquired immune response evoked by vaccination can be enhanced and steered by the innate immune system, which is triggered by interaction of an intrinsic vaccine component with a pattern recognition receptor (PRR. The insights presented here may be used to further improve the immune-stimulatory and dose-sparing properties of classic influenza vaccine formulations such as WIV, and will facilitate the development of new, even more powerful vaccines to face the next influenza pandemic.

  9. Single HA2 mutation increases the infectivity and immunogenicity of a live attenuated H5N1 intranasal influenza vaccine candidate lacking NS1.

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    Brigitte M Krenn

    Full Text Available BACKGROUND: H5N1 influenza vaccines, including live intranasal, appear to be relatively less immunogenic compared to seasonal analogs. The main influenza virus surface glycoprotein hemagglutinin (HA of highly pathogenic avian influenza viruses (HPAIV was shown to be more susceptible to acidic pH treatment than that of human or low pathogenic avian influenza viruses. The acidification machinery of the human nasal passageway in response to different irritation factors starts to release protons acidifying the mucosal surface (down to pH of 5.2. We hypothesized that the sensitivity of H5 HA to the acidic environment might be the reason for the low infectivity and immunogenicity of intranasal H5N1 vaccines for mammals. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that original human influenza viruses infect primary human nasal epithelial cells at acidic pH (down to 5.4, whereas H5N1 HPAIVs lose infectivity at pH ≤ 5.6. The HA of A/Vietnam/1203/04 was modified by introducing the single substitution HA2 58K→I, decreasing the pH of the HA conformational change. The H5N1 reassortants containing the indicated mutation displayed an increased resistance to acidic pH and high temperature treatment compared to those lacking modification. The mutation ensured a higher viral uptake as shown by immunohistochemistry in the respiratory tract of mice and 25 times lower mouse infectious dose₅₀. Moreover, the reassortants keeping 58K→I mutation designed as a live attenuated vaccine candidate lacking an NS1 gene induced superior systemic and local antibody response after the intranasal immunization of mice. CONCLUSION/SIGNIFICANCE: Our finding suggests that an efficient intranasal vaccination with a live attenuated H5N1 virus may require a certain level of pH and temperature stability of HA in order to achieve an optimal virus uptake by the nasal epithelial cells and induce a sufficient immune response. The pH of the activation of the H5 HA protein may

  10. A critical HA1 neutralizing domain of H5N1 influenza in an optimal conformation induces strong cross-protection.

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    Lanying Du

    Full Text Available The highly pathogenic avian influenza (HPAI H5N1 viruses, especially the laboratory-generated H5N1 mutants, have demonstrated the potential to cross the species barrier and infect mammals and humans. Consequently, the design of an effective and safe anti-H5N1 vaccine is essential. We previously demonstrated that the full-length hemagglutinin 1 (HA1 could induce significant neutralizing antibody response and protection. Here, we intended to identify the critical neutralizing domain (CND in an optimal conformation that can elicit strong cross-neutralizing antibodies and protection against divergent H5N1 strains. We thus constructed six recombinant proteins covering different regions of HA1 of A/Anhui/1/2005(H5N1, each of which was fused with foldon (Fd and Fc of human IgG. We found that the critical fragment fused with Fd/Fc (HA-13-263-Fdc, H5 numbering that could elicit the strongest neutralizing antibody response is located in the N-terminal region of HA1 (residues 13-263, which covers the receptor-binding domain (RBD, residues 112-263. We then constructed three additional recombinants fused with Fd plus His tag (HA-13-263-Fd-His, Fc only (HA-13-263-Fc, and His tag only (HA-13-263-His, respectively. We found that the HA-13-263-Fdc, which formed an oligomeric conformation, induced the strongest neutralizing antibody response and cross-protection against challenges of two tested H5N1 virus strains covering clade 1: A/VietNam/1194/2004 (VN/1194 or clade 2.3.4: A/Shenzhen/406H/06 (SZ/406H, while HA-13-263-Fc dimer and HA-13-263-Fd-His trimer elicited higher neutralizing antibody response and protection than HA-13-263-His monomer. These results suggest that the oligomeric form of the CND containing the RBD can be further developed as an effective and safe vaccine for cross-protection against divergent strains of H5N1 viruses.

  11. Prototype of A/Duck/Sukoharjo/Bbvw-1428-9/2012 subtipe H5N1 clade 2.3.2 as vaccine on local duck

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    Risa Indriani

    2014-06-01

    Full Text Available A/Duck/Sukoharjo/Bbvw-1428-9/2012 virus subtipe H5N1 clade 2.3.2 as seed vaccine on local duck. AI H5N1 clade 2.3.2 vaccine containing 256 HAU per dose was formulated using adjuvant ISA 71VG Montanide ™. Six groups of one day old local duck were used in this study. Three groups (10 ducks per group were vaccinated and 3 groups (9 duck per group were served control. Vaccination was conducted when the duck were three weeks old of age using single dose. Three weeks after vaccination when the duck were challenged either with HPAI H5N1 clade 2.3.2, or HPAI H5N1 clade 2.1.3 virus at dose 106 EID50/ 0.1 ml by drops intranasaly. Result showed that vaccination produced 100% protection compared to unvaccinated ducks againt HPAI subtipe H5N1 clade 2.3.2, and 100% protection againt HPAI H5N1 clade 2.1.3 (A/ck/wj/Subang-29/2007 and A/ck/wj/Smi-Part/2006, while unvaccinated ducks showed virus shedding on day 3 post infection.

  12. Oral Delivery of a Novel Attenuated Salmonella Vaccine Expressing Influenza A Virus Proteins Protects Mice against H5N1 and H1N1 Viral Infection.

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    Zenglin Pei

    Full Text Available Attenuated strains of invasive enteric bacteria, such as Salmonella, represent promising gene delivery agents for nucleic acid-based vaccines as they can be administrated orally. In this study, we constructed a novel attenuated strain of Salmonella for the delivery and expression of the hemagglutinin (HA and neuraminidase (NA of a highly pathogenic H5N1 influenza virus. We showed that the constructed Salmonella strain exhibited efficient gene transfer activity for HA and NA expression and little cytotoxicity and pathogenicity in mice. Using BALB/c mice as the model, we evaluated the immune responses and protection induced by the constructed Salmonella-based vaccine. Our study showed that the Salmonella-based vaccine induced significant production of anti-HA serum IgG and mucosal IgA, and of anti-HA interferon-γ producing T cells in orally vaccinated mice. Furthermore, mice orally vaccinated with the Salmonella vaccine expressing viral HA and NA proteins were completely protected from lethal challenge of highly pathogenic H5N1 as well as H1N1 influenza viruses while none of the animals treated with the Salmonella vaccine carrying the empty expression vector with no viral antigen expression was protected. These results suggest that the Salmonella-based vaccine elicits strong antigen-specific humoral and cellular immune responses and provides effective immune protection against multiple strains of influenza viruses. Furthermore, our study demonstrates the feasibility of developing novel attenuated Salmonella strains as new oral vaccine vectors against influenza viruses.

  13. 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.

  14. Distribution of avian influenza H5N1 viral RNA in tissues of AI-vaccinated and unvaccinated contact chickens after experimental infection.

    Science.gov (United States)

    Hassan, Mohamed K; Kilany, Walid H; Abdelwhab, E M; Arafa, Abdel-Satar; Selim, Abdullah; Samy, Ahmed; Samir, M; Le Brun, Yvon; Jobre, Yilma; Aly, Mona M

    2012-05-01

    Avian influenza due to highly pathogenic avian influenza (HPAIV) H5N1 virus is not a food-borne illness but a serious panzootic disease with the potential to be pandemic. In this study, broiler chickens were vaccinated with commercial H5N1 or H5N2 inactivated vaccines prior to being challenged with an HPAIV H5N1 (clade 2.2.1 classic) virus. Challenged and non-challenged vaccinated chickens were kept together, and unvaccinated chickens served as contact groups. Post-challenge samples from skin and edible internal organs were collected from dead and sacrificed (after a 14-day observation period) birds and tested using qRT-PCR for virus detection and quantification. H5N1 vaccine protected chickens against morbidity, mortality and transmission. Virus RNA was not detected in the meat or edible organs of chickens vaccinated with H5N1 vaccine. Conversely, H5N2 vaccine did not confer clinical protection, and a significant virus load was detected in the meat and internal organs. Phylogenetic analysis showed that the H5N1 virus vaccine and challenge virus strains are closely related. The results of the present study strongly suggest a need for proper selection of vaccines and their routine evaluation against newly emergent field viruses. These actions will help to reduce human exposure to HPAIV H5N1 virus from both infected live birds and slaughtered poultry. In addition, rigorous preventive measures should be put in place in order to minimize the public-health risks of avian influenza at the human-animal interface.

  15. Boosted influenza-specific T cell responses after H5N1 pandemic live attenuated influenza virus (pLAIV vaccination

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    Yanchun ePeng

    2015-06-01

    Full Text Available Background: In a phase I clinical trial, a H5N1 pandemic live attenuated influenza virus (pLAIV VN2004 vaccine bearing avian influenza H5N1 HA and NA genes on the A/Ann Arbor cold-adapted vaccine backbone displayed very restricted replication. We evaluated T cell responses to H5N1 pLAIV vaccination and assessed pre-existing T cell responses to to determine whether they were associated with restricted replication of the H5N1 pLAIV. Method: ELISPOT assays were performed using pools of overlapping peptides spanning the entire H5N1 proteome and the hemagglutinin (HA proteins of relevant seasonal H1N1 and H3N2 viruses. We tested stored PBMCs from 21 study subjects who received two doses of the H5N1 pLAIV. The PBMCs were collected 1 day before and 7 days after the first and second pLAIV vaccine doses, respectively. Result: T cell responses to conserved internal proteins M and NP were significantly boosted by vaccination (p=0.036. In addition, H5N1 pLAIV appeared to preferentially stimulate and boost pre-existing seasonal influenza virus HA-specific T cell responses that showed low cross-reactivity with the H5 HA. We confirmed this observation by T cell cloning and identified a novel HA-specific epitope. However, we did not find any evidence that pre-existing T cells prevented pLAIV replication and take. Conclusion: We found that cross-reactive T cell responses could be boosted by pLAIV regardless of the induction of antibody. The impact of the original antigenic sin phenomenon in a subset of volunteers, with preferential expansion of seasonal influenza-specific but not H5N1-specific T cell responses merits further investigation.

  16. The new temperature-sensitive mutation PA-F35S for developing recombinant avian live attenuated H5N1 influenza vaccine

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    Zhang Wenting

    2012-05-01

    Full Text Available Abstract Background H5N1 highly pathogenic avian influenza virus (HPAIV is continuously circulating in many Asian countries and threatening poultry industry and human population. Vaccination is the best strategy to control H5N1 HPAIV infection in poultry and transmission to human population. The aim of this study is to identify new temperature-sensitive (ts mutations for developing recombinant avian live attenuated H5N1 influenza vaccine. Findings A “6 + 2” recombinant virus C4/W1 that contained NA gene and modified HA gene from virus A/chicken/Hubei/327/2004 (H5N1 (C4, and six internal genes from virus A/duck/Hubei/W1/2004 (H9N2 (W1 was generated using reverse genetics and subsequently passaged in chicken eggs at progressively lower temperatures (32°C, 28°C and 25°C. The resulting virus acquired ts phenotype and one of its amino acid mutations, PA (F35S, was identified as ts mutation. Furthermore, when used as live attenuated vaccine, the recombinant virus with this ts mutation PA (F35S provided efficient protection for chickens against H5N1 HPAIV infection. Conclusions These findings highlight the potential of the new ts mutation PA (F35S in developing recombinant avian live attenuated H5N1 influenza vaccine.

  17. IMMUNOGENICITY OF INACTIVATED H5N1 SUBTYPE AVIAN INFLUENZA VIRUS VACCINES IN DUCKS AND GEESE%重组禽流感病毒灭活疫苗(H5N1亚型)对鸭和鹅的免疫效果观察

    Institute of Scientific and Technical Information of China (English)

    沈欣悦; 程旭; 刘梅; 尤素兰; 刘加圣; 戴亚斌

    2013-01-01

      由H5N1亚型禽流感病毒(Avian influenza virus,AIV)引起的高致病性禽流感(highly pathogenic avian influenza, HPAI)是禽类的一种烈性传染病,疫苗免疫是禽流感防控中的重要环节。本试验采用重组禽流感病毒灭活疫苗(H5N1,Re-5株)和重组禽流感病毒H5亚型二价灭活疫苗(H5N1、Re-5株+Re-4株)进行了鸭和鹅的免疫试验,对免疫鸭和鹅的抗体水平进行了动态监测。试验结果表明,两种疫苗对鸭和鹅均具有良好的免疫效果。基于试验结果提出了鸭和鹅禽流感免疫程序:2 w左右首免,4~5 w时二免,开产前三免,此后每隔4~5个月加强免疫一次。%Highly pathogenic avian influenza (HPAI) is caused by H5N1 subtype of avian influenza virus (AIV), and the vaccination plays a key role in prevention and control. In this study, ducks and geese were immunized with either inactivated avian influenza vaccine (H5N1 subtype, Re-5 strain) or bivalent inactivated avian influenza vaccine (H5N1 subtype, Re-5 strain+Re-4 strain) and hemagglutination inhibition (HI) antibody levels were detected. Both vaccines induced strong immune responses in ducks and geese. Based on these results, the proposal for the AIV vaccination program in ducks and geese should include the initial dose at 2-week-old, the second dose at 4-5-week-old, the third dose before the beginning of laying period, and further boosters at every 4-5 month interval.

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

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    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.

  19. Improvement of the efficacy of influenza vaccination (H5N1) in chicken by using extract of Cochinchina momordica seed (ECMS)

    Institute of Scientific and Technical Information of China (English)

    RAJPUT Zahid Iqbal; XIAO Chen-wen; HU Song-hua; ARIJO Abdullah G.; SOOMRO Noor Mohammad

    2007-01-01

    Seeds of a Chinese traditional medicine plant, Cochinchina momordica were used in the present study for the improvement of influenza vaccine (H5N 1) in chicken. Crude extraction from Cochinchina momordica seed (ECMS) was obtained by ethanol extraction method. In experiment No. 1, two weeks old chickens were immunized with influenza vaccine (H5N1) alone or gain were measured on 0, 7, 14 and 28th day after immunization. Results revealed that all ECMS groups numerically increased the hemagglutination inhibition (HI). It is concluded that ECMS has potential to improve the immune responses and deserve further study as an adjuvant.

  20. Two novel HLA-A*0201 T-cell epitopes in avian H5N1 viral nucleoprotein induced specific immune responses in HHD mice

    OpenAIRE

    Cheung, Ying-Kit; Cheng, Samuel Chak-Sum; Ke, Yan; Xie, Yong

    2009-01-01

    International audience; The influenza A nucleoprotein (NP) is an attractive target for avian flu vaccine development because of its high conversancy in the evolutionary chain of the virus. Here we identified two novel HLA-A*0201 restricted NP epitopes, named H5N1 NP373-381 AMDSNTLEL (NP373) and NP458-466 FQGRGVFEL (NP458), using computational bioinformatic analysis. The NP peptides showed a high binding affinity to HLA-A*0201 on T2 cells, and were able to induce the activation of the cytotoxi...

  1. Microarray analysis following infection with highly pathogenic avian influenza H5N1 virus in naive and vaccinated SPF chickens

    Science.gov (United States)

    Avian influenza (AI) is a viral disease of poultry that remains a constant threat to commercial poultry throughout the world. Within the last few years, outbreaks of highly pathogenic avian influenza (HPAI) H5N1 have originated in Southeast Asia and spread to several European, Middle Eastern, and A...

  2. A rapid Flp-In system for expression of secreted H5N1 influenza hemagglutinin vaccine immunogen in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Hanxin Lu

    Full Text Available BACKGROUND: Continuing transmissions of highly pathogenic H5N1 viruses in poultry and humans underscores the need for a rapid response to potential pandemic in the form of vaccine. Recombinant technologies for production of immunogenic hemagglutinin (HA could provide an advantage over the traditional inactivated vaccine manufacturing process. Generation of stably transfected mammalian cells secreting properly folded HA proteins is important for scalable controlled manufacturing. METHODOLOGY/PRINCIPAL FINDINGS: We have developed a Flp-In based 293 stable cell lines through targeted site-specific recombination for expression of secreted hemagglutinin (HA proteins and evaluated their immunogenicity. H5N1 globular domain HA1(1-330 and HA0(1-500 proteins were purified from the supernatants of 293 Flp-In stable cell lines. Both proteins were properly folded as confirmed by binding to H5N1-neutralizing conformation-dependent human monoclonal antibodies. The HA0 (with unmodified cleavage site was monomeric, while the HA1 contained oligomeric forms. Upon rabbit immunization, both HA proteins elicited neutralizing antibodies against the homologous virus (A/Vietnam/1203/2004, clade 1 as well as cross-neutralizing antibodies against heterologous H5N1 clade 2 strains, including A/Indonesia/5/2005. These results exceeded the human antibody responses against the inactivated sub-virion H5N1 vaccine. CONCLUSIONS/SIGNIFICANCE: Our data suggest that the 293 Flp-In system could serve as a platform for rapid expression of HA immunogens in mammalian cells from emerging influenza strains.

  3. Impact of vaccination on infection with Vietnam H5N1 high pathogenicity avian influenza virus in hens and the eggs they lay.

    Science.gov (United States)

    Bertran, Kateri; Moresco, Kira; Swayne, David E

    2015-03-10

    High pathogenicity avian influenza virus (HPAIV) infections in chickens negatively impact egg production and cause egg contamination. Previously, vaccination maintained egg production and reduced egg contamination when challenged with a North American H5N2 HPAIV. However, Asian H5N1 HPAIV infection has some characteristics of increased pathogenicity compared to other H5 HPAIV such as more rapid drop and complete cessation in egg production. Sham (vaccinated at 25 and 28 weeks of age), inactivated H5N1 Once (1X-H5-Vax; vaccinated at 28 weeks of age only) and inactivated H5N1 Twice (2X-H5-Vax; vaccinated at 25 and 28 weeks of age) vaccinated adult White Leghorn hens were challenged intranasally at 31 weeks of age with 6.1 log10 mean embryo infectious doses (EID50) of clade 2.3.2.1a H5N1 HPAIV (A/chicken/Vietnam/NCVD-675/2011) which was homologous to the inactivated vaccine. Sham-vaccinated layers experienced 100% mortality within 3 days post-challenge; laid soft and thin-shelled eggs; had recovery of virus from oral swabs and in 53% of the eggs from eggshell surface (35%), yolk (24%), and albumin (41%); and had very high titers of virus (average 7.91 log10 EID50/g) in all segments of the oviduct and ovary. By comparison, 1X- and 2X-H5-Vax challenged hens survived infection, laid similar number of eggs pre- and post-challenge, all eggs had normal egg shell quality, and had significantly fewer contaminated eggs with reduced virus quantity. The 2X-H5-Vax hens had significantly higher HI titers by the day of challenge (304 GMT) and at termination (512 GMT) than 1X-H5-Vax hens (45 GMT and 128 GMT). The current study demonstrated that AIV infections caused by clade 2.3.2.1a H5N1 variants can be effectively controlled by either double or single homologous vaccination. Published by Elsevier Ltd.

  4. Antibody titer has positive predictive value for vaccine protection against challenge with natural antigenic-drift variants of H5N1 high-pathogenicity avian influenza viruses from Indonesia

    NARCIS (Netherlands)

    D.E. Swayne (David); D.L. Suarez (David L.); E. Spackman (Erica); S. Jadhao (Samadhan); G. Dauphin (Gwenaelle); M. Kim-Torchetti (Mia); J. McGrane (James); J. Weaver (John); P. Daniels (Peter); F. Wong (Frank); P. Selleck (Paul); A. Wiyono (Agus); R. Indriani (Risa); Y. Yupiana (Yuni); E.S. Siregar (Elly Sawitri); T.Y. Prajitno (Teguh); D.J. Smith (Derek James); R.A.M. Fouchier (Ron)

    2015-01-01

    textabstractVaccines are used in integrated control strategies to protect poultry against H5N1 high-pathogenicity avian influenza (HPAI). H5N1 HPAI was first reported in Indonesia in 2003, and vaccination was initiated in 2004, but reports of vaccine failures began to emerge in mid-2005. This study

  5. Plant-based rapid production of recombinant subunit hemagglutinin vaccines targeting H1N1 and H5N1 influenza.

    Science.gov (United States)

    Shoji, Yoko; Chichester, Jessica A; Jones, Mark; Manceva, Slobodanka D; Damon, Emily; Mett, Vadim; Musiychuk, Konstantin; Bi, Hong; Farrance, Christine; Shamloul, Moneim; Kushnir, Natasha; Sharma, Satish; Yusibov, Vidadi

    2011-01-01

    In 2009, a novel H1N1 swine influenza virus was isolated from infected humans in Mexico and the United States, and rapidly spread around the world. Another virus, a highly pathogenic avian influenza virus of the H5N1 subtype, identified by the World Health Organization as a potential pandemic threat in 1997, continues to be a significant risk. While vaccination is the preferred strategy for the prevention and control of influenza infections, the traditional egg-based approach to producing influenza vaccines does not provide sufficient capacity and adequate speed to satisfy global needs to combat newly emerging strains, seasonal or potentially pandemic. Significant efforts are underway to develop and implement new cell substrates with improved efficiency for influenza vaccine development and manufacturing. In recent years, plants have been used to produce recombinant proteins including subunit vaccines and antibodies. The main advantages of using plant systems for the production of vaccine antigens against influenza are their independence from pathogenic viruses, and cost and time efficiency. Here, we describe the large-scale production of recombinant hemagglutinin proteins from A/California/04/09 (H1N1) and A/Indonesia/05/05 (H5N1) strains of influenza virus in Nicotiana benthamiana plants, and their immunogenicity (serum hemagglutination inhibition and virus neutralizing antibodies), and safety in animal models. These results support the testing of these candidate vaccines in human volunteers and also the utility of our plant expression system for large-scale recombinant influenza vaccine production.

  6. Improving adjuvanticity of quaternized chitosan-based microgels for H5N1 split vaccine by tailoring the particle properties to achieve antigen dose sparing effect.

    Science.gov (United States)

    Wang, Yue-Qi; Fan, Qing-Ze; Liu, Yan; Yue, Hua; Ma, Xiao-Wei; Wu, Jie; Ma, Guang-Hui; Su, Zhi-Guo

    2016-12-30

    In this study, we developed the quaternized chitosan microgels without chemical crosslinking as an adjuvant of H5N1 split vaccine. The microgels with pH-sensitivity, positive surface charge and good biocompatibility, have been demonstrated in favor of enhancing both humoral and cellular immune response. However, the detailed mechanism of the chitosan-based microgels to enhance antigen specific immune responses remains unclear. Therefore, we prepared the quaternized chitosan microgels with well defined quaternization degrees (QDs, 20-80%) and particle sizes (800nm-5μm) by the premix membrane emulsification technique, and investigated the effect of quaternization degree (QD) and size on the adjuvanticity of microgels. Results suggested that microgels with relatively smaller size (807nm) and moderate quaternization degree (QD 41% and 60%) were favorable for a maximum immune response. The mechanism was studied and explained by examining the characteristics of microgels and investigating the stimulation of bone-marrow derived dendritic cells (BMDCs). Moreover, they induced significantly stronger immune responses at lower antigen doses (known as antigen sparing effect) compared to aluminum adjuvant. These data indicated that a maximum immune response can be achieved by controlling properties of chitosan microgels, which also could serve as a significant guidance for rational design of chitosan-based particle adjuvant. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Analysis on the Immune Effect of Recombinant Avian Influenza H5N1 Inactivated Vaccine on Broiler Chicken%重组禽流感H5N1灭活疫苗对肉鸡的免疫效果分析

    Institute of Scientific and Technical Information of China (English)

    李再友; 程顺财; 范吉平

    2015-01-01

    To investigate the immune effect of recombinant avian influenza H5N1 inactivated vaccine on broiler chicken, 300 broilers were selected and divided into A group, B group and C group,100 broilers in each group. A group was inoculated with recombinant avian H5N1 inactivated vaccine (H5N1,Re-1),B group was inoculated with avian influenza and newcastle disease recom-binant two live vaccine (rL-H5 strain),C group was control group. The immune effect of inactivat-ed avian influenza vaccine was more obvious than that of recombinant two live vaccine.%为探讨重组禽流感H5N1灭活疫苗对肉鸡的免疫效果,本试验选取300只肉鸡,将其分为A组、B组、C组,每组各100只,其中A组用重组禽流感H5N1灭活疫苗(H5N1,Re-1株)免疫,B组选择禽流感-新城疫重组二联活疫苗(rL-H5株)免疫,C组为空白对照。结果表明,相对于禽流感-新城疫重组二联活疫苗,重组禽流感H5N1灭活疫苗的免疫效果更明显。

  8. Chronic heat stress inhibits immune responses to H5N1 vaccination through regulating CD4⁺ CD25⁺ Foxp3⁺ Tregs.

    Science.gov (United States)

    Meng, Di; Hu, Yanxin; Xiao, Chong; Wei, Tangting; Zou, Qiang; Wang, Ming

    2013-01-01

    Chronic heat stress (CHS) is known to have negative impacts on the immune responses in animals and increases their susceptibility to infections including the highly pathogenic avian influenza virus H5N1. However, the role of regulatory T cells (Tregs) in CHS immunosuppression remains largely undefined. In this study, we demonstrated a novel mechanism by which CHS suppressed both Th1 and Th2 immune responses and dramatically decreased the protective efficacy of the formalin-inactivated H5N1 vaccine against H5N1 influenza virus infection. This suppression was found to be associated with the induced generation of CD4⁺ CD25⁺ Foxp3⁺ Tregs and the increased secretions of IL-10 and TGF- β in CD4⁺ T cells. Adoptive transfer of the induced Tregs also suppressed the protective efficacy of formalin-inactivated H5N1 virus immunization. Collectively, this study identifies a novel mechanism of CHS immunosuppression mediated by regulating CD4⁺ CD25⁺ Foxp3⁺ Tregs.

  9. Effect of viral membrane fusion activity on antibody induction by influenza H5N1 whole inactivated virus vaccine

    NARCIS (Netherlands)

    Geeraedts, Felix; ter Veer, Wouter; Wilschut, Jan; Huckriede, Anke; de Haan, Aalzen

    2012-01-01

    Whole inactivated virus (WIV) influenza vaccines are more immunogenic in unprimed individuals than split-virus or subunit vaccines. In mice, this superior immunogenicity has been linked to the recognition of the viral ssRNA by endosomal TLR7 receptors in immune cells, leading to IFN alpha production

  10. A Bayesian approach to quantifying the effects of mass poultry vaccination upon the spatial and temporal dynamics of H5N1 in Northern Vietnam.

    Directory of Open Access Journals (Sweden)

    Patrick G T Walker

    2010-02-01

    Full Text Available Outbreaks of H5N1 in poultry in Vietnam continue to threaten the livelihoods of those reliant on poultry production whilst simultaneously posing a severe public health risk given the high mortality associated with human infection. Authorities have invested significant resources in order to control these outbreaks. Of particular interest is the decision, following a second wave of outbreaks, to move from a "stamping out" approach to the implementation of a nationwide mass vaccination campaign. Outbreaks which occurred around this shift in policy provide a unique opportunity to evaluate the relative effectiveness of these approaches and to help other countries make informed judgements when developing control strategies. Here we use Bayesian Markov Chain Monte Carlo (MCMC data augmentation techniques to derive the first quantitative estimates of the impact of the vaccination campaign on the spread of outbreaks of H5N1 in northern Vietnam. We find a substantial decrease in the transmissibility of infection between communes following vaccination. This was coupled with a significant increase in the time from infection to detection of the outbreak. Using a cladistic approach we estimated that, according to the posterior mean effect of pruning the reconstructed epidemic tree, two thirds of the outbreaks in 2007 could be attributed to this decrease in the rate of reporting. The net impact of these two effects was a less intense but longer-lasting wave and, whilst not sufficient to prevent the sustained spread of outbreaks, an overall reduction in the likelihood of the transmission of infection between communes. These findings highlight the need for more effectively targeted surveillance in order to help ensure that the effective coverage achieved by mass vaccination is converted into a reduction in the likelihood of outbreaks occurring which is sufficient to control the spread of H5N1 in Vietnam.

  11. Evaluating the control of HPAIV H5N1 in Vietnam: virus transmission within infected flocks reported before and after vaccination

    Directory of Open Access Journals (Sweden)

    Pfeiffer Dirk U

    2010-06-01

    Full Text Available Abstract Background Currently, the highly pathogenic avian influenza virus (HPAIV of the subtype H5N1 is believed to have reached an endemic cycle in Vietnam. We used routine surveillance data on HPAIV H5N1 poultry outbreaks in Vietnam to estimate and compare the within-flock reproductive number of infection (R0 for periods before (second epidemic wave, 2004-5; depopulation-based disease control and during (fourth epidemic wave, beginning 2007; vaccination-based disease control vaccination. Results Our results show that infected premises (IPs in the initial (exponential phases of outbreak periods have the highest R0 estimates. The IPs reported during the outbreak period when depopulation-based disease control was implemented had higher R0 estimates than IPs reported during the outbreak period when vaccination-based disease control was used. In the latter period, in some flocks of a defined size and species composition, within-flock transmission estimates were not significantly below the threshold for transmission (R0 Conclusions Our results indicate that the current control policy based on depopulation plus vaccination has protected the majority of poultry flocks against infection. However, in some flocks the determinants associated with suboptimal protection need to be further investigated as these may explain the current pattern of infection in animal and human populations.

  12. Apoptosis and Proinflammatory Cytokine Responses of Primary Mouse Microglia and Astrocytes Induced by Human H1N1 and Avian H5N1 Influenza Viruses

    Institute of Scientific and Technical Information of China (English)

    Gefei Wang; Kangsheng Li; Juan Zhang; Weizhong Li; Gang Xin; Yun Su; Yuanli Gao; Heng Zhang; Guimei Lin; Xiaoyang Jiao

    2008-01-01

    Patients with an influenza virus infection can be complicated by acute encephalopathy and encephalitis. To investigate the immune reactions involved in the neurocomplication, mouse microglia and astrocytes were isolated,infected with human H1N1 and avian H5N1 influenza viruses, and examined for their immune responses. We observed homogeneously distributed viral receptors, sialic acid (SA)-α2,3-Galactose (Gal) and SA-α2,6-Gal, on microglia and astrocytes. Both viruses were replicative and productive in microglia and astrocytes. Virus-induced apoptosis and cytopathy in infected cells were observed at 24 h post-infection (p.i.). Expression of IL-1β, IL-6 and TNF-α mRNA examined at 6 h and 24 h p.i. Was up-regulated, and their expression levels were considerably higher in H5N1 infection. The amounts of secreted proinflammatory IL-1β, IL-6 and TNF-α at 6 h and 24 h p.i. Were also induced, with greater induction by H5N1 infection. This study is the first demonstration that both human H1N1 and avian H5N1 influenza viruses can infect mouse microglia and astrocytes and induce apoptosis, cytopathy, and proinflammatory cytokine production in them in vitro. Our results suggest that the direct cellular damage and the consequences of immunopathological injury in the CNS contribute to the influenza viral pathogenesis.

  13. Production of H5N1 influenza virus matrix protein 2 ectodomain protein bodies in tobacco plants and in insect cells as a candidate universal influenza vaccine

    Directory of Open Access Journals (Sweden)

    Sandiswa Mbewana

    2015-12-01

    Full Text Available The spread of influenza A viruses is partially controlled and prevented by vaccination. The matrix protein 2 ectodomain (M2e is the most conserved sequence in influenza A viruses, and is therefore a good potential target for a vaccine to protect against multiple virus subtypes. We explored the feasibility of a M2e-based universal influenza A vaccine candidate based on the highly pathogenic avian influenza A virus, H5N1. A synthetic M2e gene was human and plant codon optimised and fused in-frame with a sequence encoding the N-terminal proline-rich domain (Zera® of the γ-zein protein of maize. Zera®M2e was expressed transiently in Nicotiana benthamiana and Sf21 baculovirus / insect cell expression systems, and Zera®M2e protein bodies (PBs were successfully produced in both expression systems. The plant-produced Zera®M2e PBs were purified and injected into Balb/c mice. Western blot analysis using insect cell-produced Zera®M2e PBs and multiple tandem M2e sequences (5xM2e fused with the avian influenza H5N1 transmembrane and cytosolic tail (5xM2e_tHA confirmed the presence of M2e-specific antibodies in immunised mice sera. The immunogenicity of the Zera®M2e indicates that our plant-produced protein has potential as an inexpensive universal influenza A vaccine.

  14. A novel hemagglutinin protein produced in bacteria protects chickens against H5N1 highly pathogenic avian influenza viruses by inducing H5 subtype-specific neutralizing antibodies

    Science.gov (United States)

    Sączyńska, Violetta; Romanik, Agnieszka; Florys, Katarzyna; Cecuda-Adamczewska, Violetta; Kęsik-Brodacka, Małgorzata; Śmietanka, Krzysztof; Olszewska, Monika; Domańska-Blicharz, Katarzyna; Minta, Zenon; Szewczyk, Bogusław; Płucienniczak, Grażyna; Płucienniczak, Andrzej

    2017-01-01

    The highly pathogenic (HP) H5N1 avian influenza viruses (AIVs) cause a mortality rate of up to 100% in infected chickens and pose a permanent pandemic threat. Attempts to obtain effective vaccines against H5N1 HPAIVs have focused on hemagglutinin (HA), an immunodominant viral antigen capable of eliciting neutralizing antibodies. The vast majority of vaccine projects have been performed using eukaryotic expression systems. In contrast, we used a bacterial expression system to produce vaccine HA protein (bacterial HA) according to our own design. The HA protein with the sequence of the H5N1 HPAIV strain was efficiently expressed in Escherichia coli, recovered in the form of inclusion bodies and refolded by dilution between two chromatographic purification steps. Antigenicity studies showed that the resulting antigen, referred to as rH5-E. coli, preserves conformational epitopes targeted by antibodies specific for H5-subtype HAs, inhibiting hemagglutination and/or neutralizing influenza viruses in vitro. The proper conformation of this protein and its ability to form functional oligomers were confirmed by a hemagglutination test. Consistent with the biochemical characteristics, prime-boost immunizations with adjuvanted rH5-E. coli protected 100% and 70% of specific pathogen-free, layer-type chickens against challenge with homologous and heterologous H5N1 HPAIVs, respectively. The observed protection was related to the positivity in the FluAC H5 test (IDVet) but not to hemagglutination-inhibiting antibody titers. Due to full protection, the effective contact transmission of the homologous challenge virus did not occur. Survivors from both challenges did not or only transiently shed the viruses, as established by viral RNA detection in oropharyngeal and cloacal swabs. Our results demonstrate that vaccination with rH5-E. coli could confer control of H5N1 HPAIV infection and transmission rates in chicken flocks, accompanied by reduced virus shedding. Moreover, the role of

  15. Preservation of the immunogenicity of dry-powder influenza H5N1 whole inactivated virus vaccine at elevated storage temperatures.

    Science.gov (United States)

    Geeraedts, Felix; Saluja, Vinay; ter Veer, Wouter; Amorij, Jean-Pierre; Frijlink, Henderik W; Wilschut, Jan; Hinrichs, Wouter L J; Huckriede, Anke

    2010-06-01

    Stockpiling of pre-pandemic influenza vaccines guarantees immediate vaccine availability to counteract an emerging pandemic. Generally, influenza vaccines need to be stored and handled refrigerated to prevent thermal degradation of the antigenic component. Requirement of a cold-chain, however, complicates stockpiling and the logistics of vaccine distribution. We, therefore, investigated the effect of elevated storage temperatures on the immunogenicity of a pre-pandemic influenza A H5N1 whole inactivated virus vaccine. Either suspended in liquid or kept as a freeze-dried powder, vaccines could be stored for 1 year at ambient temperature (20 degrees C) with minimal loss of immunogenicity in mice. Elevation of the storage temperature to 40 degrees C, however, resulted in a significant loss of immunogenic potency within 3 months if vaccines were stored in liquid suspension. In sharp contrast, freeze-dried powder formulations were stable at 40 degrees C for at least 3 months. The presence of inulin or trehalose sugar excipients during freeze-drying of the vaccine proved to be critical to maintain its immunogenic potency during storage, and to preserve the characteristic Th1-type response to whole inactivated virus vaccine. These results indicate that whole inactivated virus vaccines may be stored and handled at room temperature in moderate climate zones for over a year with minimal decline and, if converted to dry-powder, even in hot climate zones for at least 3 months. The increased stability of dry-powder vaccine at 40 degrees C may also point to an extended shelf-life when stored at 4 degrees C. Use of the more stable dry-powder formulation could simplify stockpiling and thereby facilitating successful pandemic intervention.

  16. Heterologous prime-boost vaccination with MF59-adjuvanted H5 vaccines promotes antibody affinity maturation towards the hemagglutinin HA1 domain and broad H5N1 cross-clade neutralization.

    Directory of Open Access Journals (Sweden)

    Surender Khurana

    Full Text Available In an open label clinical study (2007, MF59-adjuvanted hemagglutinin (HA vaccine from H5N1-A/Vietnam/1194/2004 (clade 1 was administered to subjects previously vaccinated (primed with clade 0 H5N3 (A/duck/Singapore/97 vaccine at least 6 years earlier (in 1999 or 2001. The primed individuals responded rapidly and generated high neutralizing antibody titers against the H5N1-Vietnam strain within 7 days of a single booster vaccination. Furthermore, significant cross-neutralization titers were measured against H5N1 clade 0, 1, and 2 viruses. In the current study, the impact of MF59 adjuvant during heterologous priming on the quality of humoral polyclonal immune response in different vaccine arms were further evaluated using real time kinetics assay by surface plasmon resonance (SPR. Total anti-H5N1 HA1 polyclonal sera antibody binding from the heterologous prime-boost groups after a single MF59-H5N1 boost was significantly higher compared with sera from unprimed individuals that received two MF59-H5N1 vaccinations. The antigen-antibody complex dissociation rates (surrogate for antibody affinity of the polyclonal sera against HA1 of H5N1-A/Vietnam/1194/2004 from the MF59-H5N3 primed groups were significantly higher compared to sera from unadjuvanted primed groups or unprimed individuals that received two MF59-H5N1 vaccines. Furthermore, strong inverse correlations were observed between the antibody dissociation off-rates of the immune sera against HA1 (but not HA2 and the virus neutralization titers against H5 vaccine strains and heterologous H5N1 strains. These findings supports the use of oil-in-water-adjuvanted pandemic influenza vaccines to elicit long term memory B cells with high affinity BCR capable of responding to potential variant pandemic viruses likely to emerge and adapt to human transmissions.

  17. Bovine adenoviral vector-based H5N1 influenza vaccine overcomes exceptionally high levels of pre-existing immunity against human adenovirus.

    Science.gov (United States)

    Singh, Neetu; Pandey, Aseem; Jayashankar, Lakshmi; Mittal, Suresh K

    2008-05-01

    Because of the high prevalence of adenovirus (Ad) infections in humans, it is believed that pre-existing Ad-neutralizing antibodies (vector immunity) may negatively impact the immune response to vaccine antigens when delivered by human Ad (HAd) vectors. In order to evaluate whether bovine Ad subtype 3 (BAd3), a non-HAd vector, can effectively elude high levels of pre-existing vector immunity, naïve and HAd serotype 5 (HAd)-primed mice were immunized with BAd-H5HA [BAd3 vector expressing the hemagglutinin (HA) gene from H5N1 influenza virus]. Even in the presence of very high levels of HAd-specific neutralizing antibody, no significant reductions in HA-specific humoral and cell-mediated immune (CMI) responses were observed in HAd-primed mice immunized with BAd-H5HA. In naïve mice immunized with HAd-H5HA (HAd5 vector expressing H5N1 HA) and boosted with BAd-H5HA, the humoral responses elicited were significantly higher (P BAd-H5HA alone, while the CMI responses were comparable in the groups. This finding underlines the importance of a heterologous prime-boost approach for achieving an enhanced immune response. The immunization of naïve or HAd-primed mice with BAd-H5HA bestowed full protection from morbidity and mortality following a potentially lethal challenge with A/Hong Kong/483/97. These results demonstrate the importance of BAd vectors as an alternate or supplement to HAd vectors for influenza pandemic preparedness.

  18. 5'PPP-RNA induced RIG-I activation inhibits drug-resistant avian H5N1 as well as 1918 and 2009 pandemic influenza virus replication

    Directory of Open Access Journals (Sweden)

    García-Sastre Adolfo

    2010-05-01

    Full Text Available Abstract Background Emergence of drug-resistant strains of influenza viruses, including avian H5N1 with pandemic potential, 1918 and 2009 A/H1N1 pandemic viruses to currently used antiviral agents, neuraminidase inhibitors and M2 Ion channel blockers, underscores the importance of developing novel antiviral strategies. Activation of innate immune pathogen sensor Retinoic Acid Inducible Gene-I (RIG-I has recently been shown to induce antiviral state. Results In the present investigation, using real time RT-PCR, immunofluorescence, immunoblot, and plaque assay we show that 5'PPP-containing single stranded RNA (5'PPP-RNA, a ligand for the intracytoplasmic RNA sensor, RIG-I can be used as a prophylactic agent against known drug-resistant avian H5N1 and pandemic influenza viruses. 5'PPP-RNA treatment of human lung epithelial cells inhibited replication of drug-resistant avian H5N1 as well as 1918 and 2009 pandemic influenza viruses in a RIG-I and type 1 interferon dependant manner. Additionally, 5'PPP-RNA treatment also inhibited 2009 H1N1 viral replication in vivo in mice. Conclusions Our findings suggest that 5'PPP-RNA mediated activation of RIG-I can suppress replication of influenza viruses irrespective of their genetic make-up, pathogenicity, and drug-sensitivity status.

  19. 禽流感病毒H5N1亚型基因工程疫苗设计、表达制备及动物实验研究%Preparation of avian influenza virus H5N1 genetic engineering vaccine and animal study

    Institute of Scientific and Technical Information of China (English)

    刘学东; 包振民; 王志亮

    2011-01-01

    measured by ELISA. The emulsified protein vaccine of avian influenza prepared was evaluated by immunization test in mice for immune effect. Results The target protein expressed in E. Coli accounted for approximately 30% of the total bacterial protein; the purity of protein was 95. 5% after purification and the concentration of soluble protein was up to 2.4 mg/ml. Immune tests proved that the vaccine effectively induced immune responses in mice. Conclusion The engineering vaccine against avian influenza virus H5N1 has been successfully prepared which can induce immune response in mice.

  20. Newcastle Disease Virus-Vectored H7 and H5 Live Vaccines Protect Chickens from Challenge with H7N9 or H5N1 Avian Influenza Viruses.

    Science.gov (United States)

    Liu, Qinfang; Mena, Ignacio; Ma, Jingjiao; Bawa, Bhupinder; Krammer, Florian; Lyoo, Young S; Lang, Yuekun; Morozov, Igor; Mahardika, Gusti Ngurah; Ma, Wenjun; García-Sastre, Adolfo; Richt, Juergen A

    2015-07-01

    Sporadic human infections by a novel H7N9 virus occurred over a large geographic region in China. In this study, we show that Newcastle disease virus (NDV)-vectored H7 (NDV-H7) and NDV-H5 vaccines are able to induce antibodies with high hemagglutination inhibition (HI) titers and completely protect chickens from challenge with the novel H7N9 or highly pathogenic H5N1 viruses, respectively. Notably, a baculovirus-expressed H7 protein failed to protect chickens from H7N9 virus infection. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. 几种野生水禽H5N1禽流感疫苗免疫效果比较%Comparison on the immune effect of several vaccines against subtype H5N1 of Avian Influenza in wild waterfowl

    Institute of Scientific and Technical Information of China (English)

    李莹; 吴秀山; 张成林; 郑常明; 黄淑芳

    2012-01-01

    This survey selected 4 species of waterfowl raised in Beijing Zoo and a group of little swan raised in Hangzhou Zoo as the object of antibody test for vaccination of subtype H5N1 of Avian Influenza.The results showed that the antibody titer achieved the peak 20 days after vaccination,then gradually decreased.The rate of antibody decline was different between species.%选择北京动物园饲养的4种雁行目水禽和杭州动物园小天鹅进行H5N1禽流感疫苗免疫,考察其免疫效果。结果表明,在免疫约20 d抗体滴度达到峰值,后逐渐下降,抗体水平下降速度因野生水禽的种类不同而不同。

  2. Analysis of Avian Influenza Virus Epitopes and the Design of H5N1 Virus Genetic Engineering Vaccine%禽流感病毒抗原表位分析及H5N1亚型基因工程疫苗设计

    Institute of Scientific and Technical Information of China (English)

    刘学东; 王志亮; 包振民

    2012-01-01

    In this study, we choose the asian H5N1 subtype avian influenza virus, use software to analyze the gene sequences of the HA1 (Hemagglutnin, HA, hemagglutinin) and NP (Nucleocapsid protein, capsid protein), and optimize major T cell epitopes and B cell epitopes of the HA1 protein and the major CTL (Cytotoxicity T lymphocyte cytotoxic T lymphocyte) epitope of the NP protein. According to these preferred epitopes, we designed the avian influenza virus subtype H5N1 recombinant vaccine. Genetically engineered vaccine expression vector pRSET-AIV was constructed, exogenous gene can be well expressed in E, coli system. Mice immunized with expression products, serum IgA and IgG antibody levels were significantly increased, IL-2, IL-4 and IFN-y cytokines were tested in vitro spleen cells. The antigen of genetic engineering was verified. It's confirmed that the vaccine stimulates the cellulat's immunity while it activates the humoral immunity.%以亚洲地区H5N1亚型禽流感病毒(Avian Influenze Virus)流行株为研究对象,利用计算机软件,对同源性较高的HA1(Hemagglutnin,HA,血凝素)和NP(Nucleocapsid protein,核衣壳蛋白)进行全基因序列分析,优选出HA1蛋白的主要T细胞表位和B细胞表位,以及NP蛋白的主要CTL(Cytotoxicity T lymphocyte,细胞毒性T淋巴细胞)表位.依据这些优选表位,设计了禽流感病毒H5N1亚型基因工程疫苗.构建了基因工程疫苗表达载体pRSET-AIV,外源基因能够在大肠杆菌表达系统中得到良好表达.表达产物免疫小鼠后,血清中IgA和IgG抗体水平明显上升,在体外培养脾细胞可产生IL-2、IL-4和IFN-γ细胞因子.验证了该H5N1亚型基因工程疫苗的抗原性,证实该基因工程疫苗在免疫小鼠体内激发体液免疫的同时调动了细胞免疫.

  3. Point-of-Use Mixing of Influenza H5N1 Vaccine and MF59 Adjuvant for Pandemic Vaccination Preparedness: Antibody Responses and Safety. A Phase 1 Clinical Trial

    Science.gov (United States)

    Mulligan, Mark J.; Bernstein, David I.; Frey, Sharon; Winokur, Patricia; Rouphael, Nadine; Dickey, Michelle; Edupuganti, Srilatha; Spearman, Paul; Anderson, Edwin; Graham, Irene; Noah, Diana L.; Mangal, Brian; Kim, Sonnie; Hill, Heather; Whitaker, Jenifer; Emery, William; Beck, Allison; Stephens, Kathy; Hartwell, Brooke; Ogilvie, Melinda; Rimann, Nayoka; Osinski, Eileen; Destefano, Ellen; Gajadhar, Theda; Strudwick, Amanda; Pierce, Karen; Lai, Lilin; Yue, Ling; Wang, Dongli; Ying, Carl; Cline, Amy; Foltz, Tara; Wagner, Nancy; Dull, Geraldine; Pacatte, Thomas; Taggart, Barbara; Johnson, Valerie; Haller, Logan; Looney, Candi; Li, Shixiong; May, Megan; Myers, Bridgette; May, Rachel; Parker, Lawanda; Cochran, Nertaissa; Bowen, Donna; Bell, Michelle; Scoggins, Jeffery; Burns, Angela; Stablein, Claire; Wolff, Mark; Jolles, Bernadette; Leung, Brenda; Lambert, Linda; Shorer, Shy; Buchanan, Wendy; Murray, Suzanne; Chang, Soju; Gorman, Richard

    2014-01-01

    Background  Avian influenza A/H5N1 has threatened human health for nearly 2 decades. Avian influenza A vaccine without adjuvant is poorly immunogenic. A flexible rapid tactic for mass vaccination will be needed if a pandemic occurs. Methods  A multicenter, randomized, blinded phase 1 clinical trial evaluated safety and antibody responses after point-of-use mixing of influenza A/Indonesia/05/2005 (H5N1) vaccine with MF59 adjuvant. Field-site pharmacies mixed 3.75, 7.5, or 15 mcg of antigen with or without MF59 adjuvant just prior to intramuscular administration on days 0 and 21 of healthy adults aged 18–49 years. Results  Two hundred and seventy subjects were enrolled. After vaccination, titers of hemagglutination inhibition antibody ≥1:40 were achieved in 80% of subjects receiving 3.75 mcg + MF59 vs only 14% receiving 15 mcg without adjuvant (P < .0001). Peak hemagglutination inhibition antibody geometric mean titers for vaccine + MF59 were ∼65 regardless of antigen dose, and neutralizing titers were 2- to 3-fold higher. Vaccine + MF59 produced cross-reactive antibody responses against 4 heterologous H5N1 viruses. Excellent safety and tolerability were demonstrated. Conclusions  Point-of-use mixing of H5N1 antigen and MF59 adjuvant achieved target antibody titers in a high percentage of subjects and was safe. The feasibility of the point-of-use mixing should be studied further. PMID:25734170

  4. 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,

  5. 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, howe

  6. Evaluation of in vitro cross-reactivity to avian H5N1 and pandemic H1N1 2009 influenza following prime boost regimens of seasonal influenza vaccination in healthy human subjects: a randomised trial.

    Directory of Open Access Journals (Sweden)

    Delia Bethell

    Full Text Available INTRODUCTION: Recent studies have demonstrated that inactivated seasonal influenza vaccines (IIV may elicit production of heterosubtypic antibodies, which can neutralize avian H5N1 virus in a small proportion of subjects. We hypothesized that prime boost regimens of live and inactivated trivalent seasonal influenza vaccines (LAIV and IIV would enhance production of heterosubtypic immunity and provide evidence of cross-protection against other influenza viruses. METHODS: In an open-label study, 26 adult volunteers were randomized to receive one of four vaccine regimens containing two doses of 2009-10 seasonal influenza vaccines administered 8 (±1 weeks apart: 2 doses of LAIV; 2 doses of IIV; LAIV then IIV; IIV then LAIV. Humoral immunity assays for avian H5N1, 2009 pandemic H1N1 (pH1N1, and seasonal vaccine strains were performed on blood collected pre-vaccine and 2 and 4 weeks later. The percentage of cytokine-producing T-cells was compared with baseline 14 days after each dose. RESULTS: Subjects receiving IIV had prompt serological responses to vaccine strains. Two subjects receiving heterologous prime boost regimens had enhanced haemagglutination inhibition (HI and neutralization (NT titres against pH1N1, and one subject against avian H5N1; all three had pre-existing cross-reactive antibodies detected at baseline. Significantly elevated titres to H5N1 and pH1N1 by neuraminidase inhibition (NI assay were observed following LAIV-IIV administration. Both vaccines elicited cross-reactive CD4+ T-cell responses to nucleoprotein of avian H5N1 and pH1N1. All regimens were safe and well tolerated. CONCLUSION: Neither homologous nor heterologous prime boost immunization enhanced serum HI and NT titres to 2009 pH1N1 or avian H5N1 compared to single dose vaccine. However heterologous prime-boost vaccination did lead to in vitro evidence of cross-reactivity by NI; the significance of this finding is unclear. These data support the strategy of

  7. DNA priming prior to inactivated influenza A(H5N1) vaccination expands the antibody epitope repertoire and increases affinity maturation in a boost-interval-dependent manner in adults.

    Science.gov (United States)

    Khurana, Surender; Wu, Jian; Dimitrova, Milena; King, Lisa R; Manischewitz, Jody; Graham, Barney S; Ledgerwood, Julie E; Golding, Hana

    2013-08-01

    DNA priming improves the response to inactivated influenza A(H5N1) vaccination. We compared the immunogenicity of an H5 DNA prime (using strain A/Indonesia/5/2005) followed by an H5N1 monovalent inactivated vaccine boost at 4, 8, 12, 16, or 24 weeks to that of 2 doses of H5N1 monovalent inactivated vaccine in adults. Antibody epitope repertoires were elucidated by genome-fragment phage-display library analysis, and antibody avidities for HA1 and HA2 domains were measured by surface plasmon resonance. H5 DNA priming expanded the H5-specific antibody epitope repertoire and enhanced antibody avidity to the HA1 (but not the HA2) domain in an interval-dependent manner. Enhanced HA1 binding and avidity after an interval of ≥12 weeks between prime and boost correlated with improved neutralization of homologous and heterologous H5N1 strains. Clinical trials registration NCT01086657.

  8. An Alternative Vaccination Approach for The Prevention of Highly Pathogenic Avian Influenza Subtype H5N1 in The Red River Delta, Vietnam —A Geospatial-Based Cost-Effectiveness Analysis

    Directory of Open Access Journals (Sweden)

    Chinh C. Tran

    2016-02-01

    Full Text Available This study addresses the tradeoff between Vietnam’s national poultry vaccination program, which implemented an annual two-round HPAI H5N1 vaccination program for the entire geographical area of the Red River Delta during the period from 2005–2010, and an alternative vaccination program which would involve vaccination for every production cycle at the recommended poultry age in high risk areas within the Delta. The ex ante analysis framework was applied to identify the location of areas with high probability of HPAI H5N1 occurrence for the alternative vaccination program by using boosted regression trees (BRT models, followed by weighted overlay operations. Cost-effectiveness of the vaccination programs was then estimated to measure the tradeoff between the past national poultry vaccination program and the alternative vaccination program. Ex ante analysis showed that the focus areas for the alternative vaccination program included 1137 communes, corresponding to 50.6% of total communes in the Delta, and located primarily in the coastal areas to the east and south of Hanoi. The cost-effectiveness analysis suggested that the alternative vaccination program would have been more successful in reducing the rate of disease occurrence and the total cost of vaccinations, as compared to the national poultry vaccination program.

  9. The Length of N-Glycans of Recombinant H5N1 Hemagglutinin Influences the Oligomerization and Immunogenicity of Vaccine Antigen

    Directory of Open Access Journals (Sweden)

    Edyta Kopera

    2017-04-01

    Full Text Available Hemagglutinin glycoprotein (HA is a principle influenza vaccine antigen. Recombinant HA-based vaccines become a potential alternative for traditional approach. Complexity and variation of HA N-glycosylation are considered as the important factors for the vaccine design. The number and location of glycan moieties in the HA molecule are also crucial. Therefore, we decided to study the effect of N-glycosylation pattern on the H5 antigen structure and its ability to induce immunological response. We also decided to change neither the number nor the position of the HA glycosylation sites but only the glycan length. Two variants of the H5 antigen with high mannose glycosylation (H5hm and with low-mannose glycosylation (H5Man5 were prepared utilizing different Pichia strains. Our structural studies demonstrated that only the highly glycosylated H5 antigen formed high molecular weight oligomers similar to viral particles. Further, the H5hm was much more immunogenic for mice than H5Man5. In summary, our results suggest that high mannose glycosylation of vaccine antigen is superior to the low glycosylation pattern. Our findings have strong implications for the recombinant HA-based influenza vaccine design.

  10. Efficacy of a Recombinant Turkey Herpesvirus H5 Vaccine Against Challenge With H5N1 Clades 1.1.2 and 2.3.2.1 Highly Pathogenic Avian Influenza Viruses in Domestic Ducks (Anas platyrhynchos domesticus).

    Science.gov (United States)

    Pantin-Jackwood, Mary J; Kapczynski, Darrell R; DeJesus, Eric; Costa-Hurtado, Mar; Dauphin, Gwenaelle; Tripodi, Astrid; Dunn, John R; Swayne, David E

    2016-03-01

    Domestic ducks are the second most abundant poultry species in many Asian countries and have played a critical role in the epizootiology of H5N1 highly pathogenic avian influenza (HPAI).In this study, the protective efficacy of a live recombinant vector vaccine based on a turkey herpesvirus (HVT) expressing the H5 gene from a clade 2.2 H5N1 HPAI strain (A/Swan/Hungary/4999/ 2006) (rHVT-H5/2.2), given at 3 days of age, was examined in Pekin ducks (Anas platyrhynchos domesticus). The vaccine was given alone or in combination with an inactivated H5N1 clade 2.3.2.1 reverse genetic (rgGD/2.3.2.1) vaccine given at 16 days of age, either as a single vaccination or in a prime-boost regime. At 30 days of age, ducks were challenged with one of two H5N1 HPAI viruses: A/duck/Vietnam/NCVD-2721/2013 (clade 1.1.2) or A/duck/Vietnam/NCVD-1584/2012 (clade 2.3.2.1.C). These viruses produced 100% mortality in less than 5 days in nonvaccinated control ducks. Ducks vaccinated with the rgGD/2.3.2.1 vaccine, with or without the rHVT-H5/2.2 vaccine, were 90%-100% protected against mortality after challenge with either of the two H5N1 HPAI viruses. The rHVT-H5/2.2 vaccine alone, however, conferred only 30% protection against mortality after challenge with either H5N1 HPAI virus; the surviving ducks from these groups shed higher amount of virus and for longer than the single-vaccinated rgGD/2.3.2.1 group. Despite low protection, ducks vaccinated with the rHVT-H5/2.2 vaccine and challenged with the clade 1.1.2 Vietnam virus had a longer mean death time than nonvaccinated controls (P = 0.02). A booster effect was found on reduction of virus shedding when using both vaccines, with lower oropharyngeal viral titers at 4 days after challenge with either HPAI virus (P vaccine could be detected in samples collected from multiple tissues at different time points, indicting minimal levels of viral replication. In conclusion, although a minor effect on survival was observed, this study demonstrates

  11. Cloning of M and NP Gene of H5N1 Avian Influenza Virus and Immune Efficacy of their DNA Vaccines

    Institute of Scientific and Technical Information of China (English)

    Hong-bo FAN; Jun-wei LI; Zhi-lin LI; Wei ZHENG; Po Tien; De-yin GUO

    2007-01-01

    The M and NP genes of H5N1 avian influenza virus (A/chicken/Hubei/489/2004) were amplified by RT-PCR from viral RNA,and cloned into pMD 18-T vector respectively.The expression plasmid containing the M gene (pHM6-m) or the NP gene (pHM6-np) was then constructed by inserting the M or NP gene into the pHM6 eukaryote expression vector; the constructed plasmid was then sequenced.32 BALB/c mice (6-week-old) were divided into four groups at random.Three groups of BALB/c mice were inoculated one time the intramuscular route with either 30 μg of plasmid pHM6-m,30 μg of plasmid pHM6-np or the mixture of plasmid pHM6-m (15 μg ) and pHM6-np(15 μg) respectively.A additional group of mice were injected with 100 μ1 PBS as controls.Two weeks later,all mice were challenged with homologous H5N1 avian influenza virus,and observed in the following 12 days.The survival rates of mice in the pHM6-m group,the pHM6-np group and mixed plasmids group were 62.5% ,25.0% and 50.0%,respectively.Results showed that effective protection could be provided by either pHM6-m or pHM6-np,but pHM6-m provided a better protective effect than pHM6-np.

  12. Heterosubtype neutralizing responses to influenza A (H5N1 viruses are mediated by antibodies to virus haemagglutinin.

    Directory of Open Access Journals (Sweden)

    Jean-Michel Garcia

    Full Text Available BACKGROUND: It is increasingly clear that influenza A infection induces cross-subtype neutralizing antibodies that may potentially confer protection against zoonotic infections. It is unclear whether this is mediated by antibodies to the neuraminidase (NA or haemagglutinin (HA. We use pseudoviral particles (H5pp coated with H5 haemagglutinin but not N1 neuraminidase to address this question. In this study, we investigate whether cross-neutralizing antibodies in persons unexposed to H5N1 is reactive to the H5 haemagglutinin. METHODOLOGY/PRINCIPAL FINDINGS: We measured H5-neutralization antibody titers pre- and post-vaccination using the H5N1 micro-neutralization test (MN and H5pp tests in subjects given seasonal vaccines and in selected sera from European elderly volunteers in a H5N1 vaccine trial who had detectable pre-vaccination H5N1 MN antibody titers. We found detectable (titer > or = 20 H5N1 neutralizing antibodies in a minority of pre-seasonal vaccine sera and evidence of a serological response to H5N1 in others after seasonal influenza vaccination. There was excellent correlation in the antibody titers between the H5N1 MN and H5pp tests. Similar correlations were found between MN and H5pp in the pre-vaccine sera from the cohort of H5N1 vaccine trial recipients. CONCLUSIONS/SIGNIFICANCE: Heterosubtype neutralizing antibody to H5N1 in healthy volunteers unexposed to H5N1 is mediated by cross-reaction to the H5 haemagglutinin.

  13. 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.

  14. A triclade DNA vaccine designed on the basis of a comprehensive serologic study elicits neutralizing antibody responses against all clades and subclades of highly pathogenic avian influenza H5N1 viruses.

    Science.gov (United States)

    Zhou, Fan; Wang, Guiqin; Buchy, Philippe; Cai, Zhipeng; Chen, Honglin; Chen, Zhiwei; Cheng, Genhong; Wan, Xiu-Feng; Deubel, Vincent; Zhou, Paul

    2012-06-01

    Because of their rapid evolution, genetic diversity, broad host range, ongoing circulation in birds, and potential human-to-human transmission, H5N1 influenza viruses remain a major global health concern. Their high degree of genetic diversity also poses enormous burdens and uncertainties in developing effective vaccines. To overcome this, we took a new approach, i.e., the development of immunogens based on a comprehensive serologic study. We constructed DNA plasmids encoding codon-optimized hemagglutinin (HA) from 17 representative strains covering all reported clades and subclades of highly pathogenic avian influenza H5N1 viruses. Using DNA plasmids, we generated the corresponding H5N1 pseudotypes and immune sera. We performed an across-the-board pseudotype-based neutralization assay and determined antigenic clusters by cartography. We then designed a triclade DNA vaccine and evaluated its immunogenicity and protection in mice. We report here that (sub)clades 0, 1, 3, 4, 5, 6, 7.1, and 9 were grouped into antigenic cluster 1, (sub)clades 2.1.3.2, 2.3.4, 2.4, 2.5, and 8 were grouped into another antigenic cluster, with subclade 2.2.1 loosely connected to it, and each of subclades 2.3.2.1 and 7.2 was by itself. Importantly, the triclade DNA vaccine encoding HAs of (sub)clades 0, 2.3.2.1, and 7.2 elicited broadly neutralizing antibody responses against all H5 clades and subclades and protected mice against high-lethal-dose heterologous H5N1 challenge. Thus, we conclude that broadly neutralizing antibodies against all H5 clades and subclades can indeed be elicited with immunogens on the basis of a comprehensive serologic study. Further evaluation and optimization of such an approach in ferrets and in humans is warranted.

  15. Comprehensive Serological Analysis of Two Successive Heterologous Vaccines against H5N1 Avian Influenza Virus in Exotic Birds in Zoos▿

    Science.gov (United States)

    Vergara-Alert, Júlia; Fernández-Bellon, Hugo; Busquets, Núria; Alcántara, Gabriel; Delclaux, María; Pizarro, Bienvenido; Sánchez, Celia; Sánchez, Azucena; Majó, Natàlia; Darji, Ayub

    2011-01-01

    In 2005, European Commission directive 2005/744/EC allowed controlled vaccination against avian influenza (AI) virus of valuable avian species housed in zoos. In 2006, 15 Spanish zoos and wildlife centers began a vaccination program with a commercial inactivated H5N9 vaccine. Between November 2007 and May 2008, birds from 10 of these centers were vaccinated again with a commercial inactivated H5N3 vaccine. During these campaigns, pre- and postvaccination samples from different bird orders were taken to study the response against AI virus H5 vaccines. Sera prior to vaccinations with both vaccines were examined for the presence of total antibodies against influenza A nucleoprotein (NP) by a commercial competitive enzyme-linked immunosorbent assay (cELISA). Humoral responses to vaccination were evaluated using a hemagglutination inhibition (HI) assay. In some taxonomic orders, both vaccines elicited comparatively high titers of HI antibodies against H5. Interestingly, some orders, such as Psittaciformes, which did not develop HI antibodies to either vaccine formulation when used alone, triggered notable HI antibody production, albeit in low HI titers, when primed with H5N9 and during subsequent boosting with the H5N3 vaccine. Vaccination with successive heterologous vaccines may represent the best alternative to widely protect valuable and/or endangered bird species against highly pathogenic AI virus infection. PMID:21430124

  16. Comprehensive serological analysis of two successive heterologous vaccines against H5N1 avian influenza virus in exotic birds in zoos.

    Science.gov (United States)

    Vergara-Alert, Júlia; Fernández-Bellon, Hugo; Busquets, Núria; Alcántara, Gabriel; Delclaux, María; Pizarro, Bienvenido; Sánchez, Celia; Sánchez, Azucena; Majó, Natàlia; Darji, Ayub

    2011-05-01

    In 2005, European Commission directive 2005/744/EC allowed controlled vaccination against avian influenza (AI) virus of valuable avian species housed in zoos. In 2006, 15 Spanish zoos and wildlife centers began a vaccination program with a commercial inactivated H5N9 vaccine. Between November 2007 and May 2008, birds from 10 of these centers were vaccinated again with a commercial inactivated H5N3 vaccine. During these campaigns, pre- and postvaccination samples from different bird orders were taken to study the response against AI virus H5 vaccines. Sera prior to vaccinations with both vaccines were examined for the presence of total antibodies against influenza A nucleoprotein (NP) by a commercial competitive enzyme-linked immunosorbent assay (cELISA). Humoral responses to vaccination were evaluated using a hemagglutination inhibition (HI) assay. In some taxonomic orders, both vaccines elicited comparatively high titers of HI antibodies against H5. Interestingly, some orders, such as Psittaciformes, which did not develop HI antibodies to either vaccine formulation when used alone, triggered notable HI antibody production, albeit in low HI titers, when primed with H5N9 and during subsequent boosting with the H5N3 vaccine. Vaccination with successive heterologous vaccines may represent the best alternative to widely protect valuable and/or endangered bird species against highly pathogenic AI virus infection.

  17. Preservation of the immunogenicity of dry-powder influenza H5N1 whole inactivated virus vaccine at elevated storage temperatures

    NARCIS (Netherlands)

    Geeraedts, Felix; Saluja, Vinay; ter Veer, Wouter; Amorij, Jean-Pierre; Frijlink, Henderik W.; Wilschut, Jan; Hinrichs, Wouter L.J.; Huckriede, Anke

    2010-01-01

    Stockpiling of pre-pandemic influenza vaccines guarantees immediate vaccine availability to counteract an emerging pandemic. Generally, influenza vaccines need to be stored and handled refrigerated to prevent thermal degradation of the antigenic component. Requirement of a cold-chain, however, compl

  18. Technology transfer of oil-in-water emulsion adjuvant manufacturing for pandemic influenza vaccine production in Romania: Preclinical evaluation of split virion inactivated H5N1 vaccine with adjuvant.

    Science.gov (United States)

    Stavaru, Crina; Onu, Adrian; Lupulescu, Emilia; Tucureanu, Catalin; Rasid, Orhan; Vlase, Ene; Coman, Cristin; Caras, Iuliana; Ghiorghisor, Alina; Berbecila, Laurentiu; Tofan, Vlad; Bowen, Richard A; Marlenee, Nicole; Hartwig, Airn; Bielefeldt-Ohmann, Helle; Baldwin, Susan L; Van Hoeven, Neal; Vedvick, Thomas S; Huynh, Chuong; O'Hara, Michael K; Noah, Diana L; Fox, Christopher B

    2016-04-02

    Millions of seasonal and pandemic influenza vaccine doses containing oil-in-water emulsion adjuvant have been administered in order to enhance and broaden immune responses and to facilitate antigen sparing. Despite the enactment of a Global Action Plan for Influenza Vaccines and a multi-fold increase in production capabilities over the past 10 years, worldwide capacity for pandemic influenza vaccine production is still limited. In developing countries, where routine influenza vaccination is not fully established, additional measures are needed to ensure adequate supply of pandemic influenza vaccines without dependence on the shipment of aid from other, potentially impacted first-world countries. Adaptation of influenza vaccine and adjuvant technologies by developing country influenza vaccine manufacturers may enable antigen sparing and corresponding increases in global influenza vaccine coverage capacity. Following on previously described work involving the technology transfer of oil-in-water emulsion adjuvant manufacturing to a Romanian vaccine manufacturing institute, we herein describe the preclinical evaluation of inactivated split virion H5N1 influenza vaccine with emulsion adjuvant, including immunogenicity, protection from virus challenge, antigen sparing capacity, and safety. In parallel with the evaluation of the bioactivity of the tech-transferred adjuvant, we also describe the impact of concurrent antigen manufacturing optimization activities. Depending on the vaccine antigen source and manufacturing process, inclusion of adjuvant was shown to enhance and broaden functional antibody titers in mouse and rabbit models, promote protection from homologous virus challenge in ferrets, and facilitate antigen sparing. Besides scientific findings, the operational lessons learned are delineated in order to facilitate adaptation of adjuvant technologies by other developing country institutes to enhance global pandemic influenza preparedness.

  19. Vaccine protection of turkeys against H5N1 highly pathogenic avian influenza virus with a recombinant HVT expressing the hemagglutinin gene of avian influenza

    Science.gov (United States)

    Outbreaks of H5 highly pathogenic avian influenza (HPAI) in commercial poultry are a constant threat to animal health and food supplies. While vaccination can enhance protection and reduce the spread of disease, there is considerable evidence that the level of immunity required for protection varies...

  20. Comparison of potency required for protection against H7N3 or H5N1 highly pathogenic avian influenza following vaccination and challenge with homologous virus

    Science.gov (United States)

    Outbreaks of H5 and H7 highly pathogenic avian influenza (HPAI) in commercial poultry are a constant threat to food supplies and animal/human health. While vaccination can enhance protection and reduce the spread of disease, there is considerable evidence that the level of immunity required for pro...

  1. H5N1 avian influenza in China

    Institute of Scientific and Technical Information of China (English)

    CHEN HuaLan

    2009-01-01

    H5N1 highly pathogenic avian influenza virus was first detected in a goose in Guangdong Province of China in 1996. Multiple genotypes of H5N1 viruses have been identified from apparently healthy wa-terfowl since 1999. In the years 2004-2008, over 100 outbreaks in domestic poultry occurred in 23 provinces and caused severe economic damage to the poultry industry in China. Beginning from 2004, a culling plus vaccination strategy has been implemented for the control of epidemics. Since then, over 35420000 poultry have been depopulated, and over 55 billion doses of the different vaccines have been used to control the outbreaks. Although it is logistically impossible to vaccinate every single bird in China due to the large poultry population and the complicated rearing styles, there is no doubt that the increased vaccination coverage has resulted in decreased disease epidemic and environmental virus loading. The experience in China suggests that vaccination has played an important role in the protec-tion of poultry from H5N1 virus infection, the reduction of virus load in the environment, and the pre-vention of H5N1 virus transmission from poultry to humans.

  2. H5N1 avian influenza in China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    H5N1 highly pathogenic avian influenza virus was first detected in a goose in Guangdong Province of China in 1996. Multiple genotypes of H5N1 viruses have been identified from apparently healthy waterfowl since 1999. In the years 2004-2008, over 100 outbreaks in domestic poultry occurred in 23 provinces and caused severe economic damage to the poultry industry in China. Beginning from 2004, a culling plus vaccination strategy has been implemented for the control of epidemics. Since then, over 35420000 poultry have been depopulated, and over 55 billion doses of the different vaccines have been used to control the outbreaks. Although it is logistically impossible to vaccinate every single bird in China due to the large poultry population and the complicated rearing styles, there is no doubt that the increased vaccination coverage has resulted in decreased disease epidemic and environmental virus loading. The experience in China suggests that vaccination has played an important role in the protection of poultry from H5N1 virus infection, the reduction of virus load in the environment, and the prevention of H5N1 virus transmission from poultry to humans.

  3. Changes in and shortcomings of control strategies, drug stockpiles, and vaccine development during outbreaks of avian influenza A H5N1, H1N1, and H7N9 among humans.

    Science.gov (United States)

    Mei, Lin; Song, Peipei; Tang, Qi; Shan, Ke; Tobe, Ruoyan Gai; Selotlegeng, Lesego; Ali, Asghar Hammad; Cheng, Yangyang; Xu, Lingzhong

    2013-04-01

    The purpose of this review is to provide a reference for the future prevention and control of emerging infectious diseases by summarizing the control strategies, the status of drugs and vaccines, and shortcomings during three major outbreaks of avian influenza among humans (H5N1 in 2003, H1N1 in 2009, and H7N9 in 2013). Data on and documents regarding the three influenza outbreaks have been reviewed. Results indicated that the response to pandemic influenza outbreaks has improved markedly in terms of control strategies, stockpiles of antivirals, and vaccine development. These improvements also suggest advances in disease surveillance, transparency in reporting, and regional collaboration and cooperation. These trends also foreshadow better prospects for prevention and control of emerging infectious diseases. However, there are shortcomings since strategies failed to focus on high-risk groups, quantitative and measurable results (both direct and indirect) were unclear, and quantitative assessment is still lacking.

  4. 重组禽流感病毒二价灭活疫苗对H5N1亚型7.2分支病毒的攻毒保护性研究%Protection efficacy of avian influenza ressortant virus bivalent inactivated vaccines against the H5N1 clade 7.2 virus

    Institute of Scientific and Technical Information of China (English)

    曾显营; 刘丽玲; 张盼涛; 杨婧; 刘景利; 徐佳; 田国彬; 陈化兰

    2012-01-01

    为有效防控2006年以来出现的H5亚型7.2分支禽流感病毒(AIV)引起的免疫鸡群高致病性禽流感(HPAI)的流行,我们构建了重组AIV Re-4疫苗株,研制出含有重组AIV Re-4株的H5亚型二价系列灭活疫苗,并在我国北方地区使用,有效地控制了其流行.2012年我国北方地区再次出现7.2分支病毒引起的HPAI疫情.为评估现有H5亚型二价系列灭活疫苗对该分支病毒的免疫保护效力,本研究首先通过SPF鸡进行免疫攻毒试验评估.结果表明,分别以每羽份(0.3 mL/只)的Re-5+Re-4株和Re-6+Re-4株重组AIV H5二价油乳剂灭活疫苗免疫SPF鸡,免疫3周后针对重组AIV Re-4株的HI抗体均达到8 log2以上;经鼻腔接种7.2分支AIV CK/NX/2/12株(100 LD50)攻毒后,免疫鸡均获得完全保护,即无任何临床症状和排毒现象,而对照组SPF鸡全部发病死亡.此外,以哈尔滨当地养殖场中免疫H5亚型AIV灭活疫苗的48只商品蛋鸡进行攻毒试验,结果显示,商品蛋鸡血清中针对重组AIV Re-4株HI抗体平均滴度为8.3 log2,采用相同方式攻毒后也获得完全保护.本研究结果表明,Re-5+Re-4株和Re-6-Re-4株重组AIV H5二价灭活疫苗均能够对H5亚型7.2分支病毒的攻击提供良好的免疫保护效果.%The clade 7.2 H5N1 subtype avian influenza virus (AIV) emerged in 2006 and caused the outbreaks in vaccinated chicken flocks. We then developed a H5 subtype reassortant AIV of Re-4 vaccine strain as a critical portion of AIV combination inactivated vaccine, which had efficiently controlled the prevalence of clade 7.2 virus in North of China. However, the clade 7.2 virus re-emerged in 2012. It is necessary to evaluate the H5 bivalent inactivated vaccines of Re-5+Re-4 and Re-6+Re-4 against the clade 7.2 virus. In the present study, two groups of SPF chickens were vaccinated with 1 dose of either Re-5+Re-4 or Re-6+Re-4 inactivated vaccine and challenged intranasally with 100 LD50 of clade 7.2 virus (CK/NX/2/12) at

  5. Highly Pathogenic H5N1 and Novel H7N9 Influenza A Viruses Induce More Profound Proteomic Host Responses than Seasonal and Pandemic H1N1 Strains.

    Science.gov (United States)

    Simon, Philippe François; McCorrister, Stuart; Hu, Pingzhao; Chong, Patrick; Silaghi, Alex; Westmacott, Garrett; Coombs, Kevin M; Kobasa, Darwyn

    2015-11-01

    Influenza A viruses (IAV) are important human and animal pathogens with potential for causing pandemics. IAVs exhibit a wide spectrum of clinical illness in humans, from relatively mild infections by seasonal strains to acute respiratory distress syndrome during infections with some highly pathogenic avian influenza (HPAI) viruses. In the present study, we infected A549 human cells with seasonal H1N1 (sH1N1), 2009 pandemic H1N1 (pdmH1N1), or novel H7N9 and HPAI H5N1 strains. We used multiplexed isobaric tags for relative and absolute quantification to measure proteomic host responses to these different strains at 1, 3, and 6 h post-infection. Our analyses revealed that both H7N9 and H5N1 strains induced more profound changes to the A549 global proteome compared to those with low-pathogenicity H1N1 virus infection, which correlates with the higher pathogenicity these strains exhibit at the organismal level. Bioinformatics analysis revealed important modulation of the nuclear factor erythroid 2-related factor 2 (NRF2) oxidative stress response in infection. Cellular fractionation and Western blotting suggested that the phosphorylated form of NRF2 is not imported to the nucleus in H5N1 and H7N9 virus infections. Fibronectin was also strongly inhibited in infection with H5N1 and H7N9 strains. This is the first known comparative proteomic study of the host response to H7N9, H5N1, and H1N1 viruses and the first time NRF2 is shown to be implicated in infection with highly pathogenic strains of influenza.

  6. 湖北省部分地区规模化蛋鸡场H5N1 Re-6亚型禽流感疫苗免疫效果调查%INVESTIGATION INTO FIELD EFFICACY OF H5N1 RE-6 AVIAN INFLUENZA VIRUS VACCINE ON LAYER FARMS IN HUBEI

    Institute of Scientific and Technical Information of China (English)

    汪招雄; 杨玉莹; 欧阳金旭; 杨丰利; 江涛; 陈雪娇

    2015-01-01

    禽流感(avian influenza,AI)是由A型流感病毒(Avian influenza virus,AIV)感染禽类引起的一种从呼吸系统到全身严重败血症等多种症状的高度接触性传染病.目前,对我国家禽产业危害最大的高致病性禽流感病毒是H5禽流感病毒,几乎所有的规模化蛋鸡场都进行了H5禽流感疫苗的预防接种.为了解湖北省规模化蛋鸡场H5N1 Re-6亚型疫苗免疫后抗体滴度,本研究于2014年1~12月期间在湖北省13个地区选择不同规模化蛋鸡场,随机采集2079份蛋鸡血样,用血凝抑制(hemagglutinationinhibition,HI)实验检测了H5N1 Re-6亚型禽流感抗体,并对测定结果进行了统计与分析.结果显示,规模化蛋鸡场H5N1 Re-6亚型抗体滴度在6 1og2以上的样品数占89.2%,能够保护鸡群抵抗同型病毒的感染.但H5N1 Re-6亚型禽流感抗体滴度整体不高,且仍有少量地区H5N1 Re-6亚型禽流感免疫合格率为60%~80%,提示部分鸡群一旦感染该型病毒,仍然存在发病的危险.

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

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    Graeme E Price

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSION/SIGNIFICANCE: 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.

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

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    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.

  9. Hemagglutinin from the H5N1 virus activates Janus kinase 3 to dysregulate innate immunity.

    Directory of Open Access Journals (Sweden)

    Wei Xu

    Full Text Available Highly pathogenic avian influenza viruses (HPAIVs cause severe disease in humans. There are no effective vaccines or antiviral therapies currently available to control fatal outbreaks due in part to the lack of understanding of virus-mediated immunopathology. In our study, we used hemagglutinin (HA of H5N1 virus to investigate the related signaling pathways and their relationship to dysregulated innate immune reaction. We found the HA of H5N1 avian influenza triggered an abnormal innate immune signalling in the pulmonary epithelial cells, through an unusual process involving activation of Janus kinase 3 (JAK3 that is exclusively associated with γc chain and is essential for signaling via all γc cytokine receptors. By using a selective JAK3 inhibitor and JAK3 knockout mice, we have, for the first time, demonstrated the ability to target active JAK3 to counteract injury to the lungs and protect immunocytes from acute hypercytokinemia -induced destruction following the challenge of H5N1 HA in vitro and in vivo. On the basis of the present data, it appears that the efficacy of selective JAK3 inhibition is likely based on its ability to block multiple cytokines and protect against a superinflammatory response to pathogen-associated molecular patterns (PAMPs attack. Our findings highlight the potential value of selective JAK3 inhibitor in treating the fatal immunopathology caused by H5N1 challenge.

  10. Highly pathogenic avian influenza A(H5N1) mutants transmissible by air are susceptible to human and animal neutralizing antibodies.

    Science.gov (United States)

    Du, Lanying; Li, Ye; Zhao, Guangyu; Wang, Lili; Zou, Peng; Lu, Lu; Zhou, Yusen; Jiang, Shibo

    2013-10-15

    A laboratory-generated reassortant H5 hemagglutinin (HA)/influenza A(H1N1) strain containing 4 mutations in influenza A(H5N1) HA has become transmissible by air among mammals. Here, we constructed 15 influenza A(H5N1) pseudoviruses containing a single mutation or a combination of mutations and showed that the pseudoviruses were susceptible to neutralizing antibodies from patients with influenza A(H5N1) infection and from mice immunized with a vaccine containing the conserved HA1 sequence of influenza A(H5N1). These results indicate that antibodies in patients currently infected by influenza A(H5N1) and antibodies induced by vaccines containing conserved sequences in HA1 of wild-type influenza A(H5N1) are highly effective in cross-neutralizing future influenza A(H5N1) mutants with airborne transmissibility, suggesting that human influenza pandemics caused by these influenza A(H5N1) variants can be prevented.

  11. Avian influenza a (H5N1): A preliminary review

    OpenAIRE

    Padhi S.; Panigrahi P; Mahapatra A; Mahapatra S

    2004-01-01

    Humanity has been at the receiving end of many viral diseases since ages. Sudden emergence and re-emergence of new viral diseases in human beings has surprised the medical scientists from time to time. "Avian influenza" or "Bird flu" by H5N1 epidemics is one such surprise. Although many aspects about this disease are clear, there are some dark areas regarding vaccine development that need to be further explored and understood, so as to effectively contain the spread of this disease. The prese...

  12. Avian influenza a (H5N1: A preliminary review

    Directory of Open Access Journals (Sweden)

    Padhi S

    2004-01-01

    Full Text Available Humanity has been at the receiving end of many viral diseases since ages. Sudden emergence and re-emergence of new viral diseases in human beings has surprised the medical scientists from time to time. "Avian influenza" or "Bird flu" by H5N1 epidemics is one such surprise. Although many aspects about this disease are clear, there are some dark areas regarding vaccine development that need to be further explored and understood, so as to effectively contain the spread of this disease. The present article details out almost everything known about this interesting disease along with the review of the recent literature.

  13. Genetic versus antigenic differences among highly pathogenic H5N1 avian influenza A viruses

    NARCIS (Netherlands)

    Peeters, Ben; Reemers, Sylvia; Dortmans, Jos; Vries, de Erik; Jong, de Mart; Zande, van de Saskia; Rottier, Peter J.M.; Haan, de Cornelis A.M.

    2017-01-01

    Highly pathogenic H5N1 avian influenza A viruses display a remarkable genetic and antigenic diversity. We examined to what extent genetic distances between several H5N1 viruses from different clades correlate with antigenic differences and vaccine performance. H5-specific antisera were generated, an

  14. PEMBUATAN DAN STANDARISASI ANTIGEN AI H5N1 KOMERSIAL UNTUK MONITORING TITER ANTIBODI HASIL VAKSINASI AI DI INDUSTRI PETERNAKAN AYAM

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    Retno D. Soejoedono

    2012-04-01

    Full Text Available Vaccination is one of the chosen strategy for controling AI H5N1 in Indonesia. Vaccination able to induce protective antibodies against AI but unable to inhibit viral infection. Determination of antibody titers in the serum from bird vaccinated with AI-H5N1 vaccine consisting of 2 or 3 different AI virus isolates difficult to be meassured if the antigen for HI test is uncalibrated yet. Furthermore, the determination of a minimum protective antibody titer against the challenge of AI virus circulating in the field at this time needs to be done. This study aims to determine the H5N1 AI virus antigen for standart HI test and the minimum titre of antibodies that able neutralize virus infection. As much as 55 chickens were divided into 11 groups, 10 groups vaccinated with commercial AI vaccine and AI H5N1 field isolat antigen. Four types of commercial vaccines were veccinated to one group and seven other groups vaccinated with the antigen AI Legok 2004, Nagrak Ag 2009, Ag Lawang 2010, as well as polyvalent Ag combination of these three types of antigen. After third vaccinations, the presence of antibodieswere meassured by HI test. Serum with a titer test 26-28 were tested for the capability of virus neutralizationin using virus neutralization test against three different H5N1 AI virus field isolates. The test results showed that the H5N1 subtype AI virus antigen representative as standart antigen for HI test is antigen Legok 2004 and the minimum titer which able neutralize H5N1 AI virus field isolates 28

  15. 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.

  16. Intranasal Immunization of Mice to Avoid Interference of Maternal Antibody against H5N1 Infection.

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    Fenghua Zhang

    Full Text Available Maternally-derived antibodies (MDAs can protect offspring against influenza virus infection but may also inhibit active immune responses. To overcome MDA- mediated inhibition, active immunization of offspring with an inactivated H5N1 whole-virion vaccine under the influence of MDAs was explored in mice. Female mice were vaccinated twice via the intraperitoneal (IP or intranasal (IN route with the vaccine prior to mating. One week after birth, the offspring were immunized twice via the IP or IN route with the same vaccine and then challenged with a lethal dose of a highly homologous virus strain. The results showed that, no matter which immunization route (IP or IN was used for mothers, the presence of MDAs severely interfered with the active immune response of the offspring when the offspring were immunized via the IP route. Only via the IN immunization route did the offspring overcome the MDA interference. These results suggest that intranasal immunization could be a suitable inoculation route for offspring to overcome MDA interference in the defense against highly pathogenic H5N1 virus infection. This study may provide references for human and animal vaccination to overcome MDA-induced inhibition.

  17. Evaluating the immunogenicity and safety of a BiondVax-developed universal influenza vaccine (Multimeric-001) either as a standalone vaccine or as a primer to H5N1 influenza vaccine : Phase IIb study protocol

    NARCIS (Netherlands)

    van Doorn, Eva; Liu, Heng; Ben-Yedidia, Tamar; Hassin, Shimon; Visontai, Ildiko; Norley, Stephen; Frijlink, Henderik W; Hak, Eelko

    2017-01-01

    INTRODUCTION: Influenza is a major respiratory viral infection of humans with high mortality and morbidity rates and profound economic impact. Although influenza vaccines are generally updated yearly to match the viruses expected in the coming season, genetic mutation and reassortment can result in

  18. Evaluation of In Vitro Cross-Reactivity to Avian H5N1 and Pandemic H1N1 2009 Influenza Following Prime Boost Regimens of Seasonal Influenza Vaccination in Healthy Human Subjects: A Randomised Trial

    Science.gov (United States)

    2013-03-26

    washed, and specific enzyme substrate added. The reactions were stopped with 1 N sulphuric acid . The absorbance was measured at 490 nm. The average A490...California/04/2009 (H1N1) (122 15 mer peptide overlapping by 11 amino acids ) or A/Vietnam/1194/2004 (H5N1) (121 15 mer peptide overlapping by 11 amino... acids ) at a final concentration of each peptide of 1 mg/ml. NP is the main viral protein recognized by cross reactive T cells [12]. All stimulated PBMC

  19. Angiotensin-converting enzyme 2 protects from lethal avian influenza A H5N1 infections.

    Science.gov (United States)

    Zou, Zhen; Yan, Yiwu; Shu, Yuelong; Gao, Rongbao; Sun, Yang; Li, Xiao; Ju, Xiangwu; Liang, Zhu; Liu, Qiang; Zhao, Yan; Guo, Feng; Bai, Tian; Han, Zongsheng; Zhu, Jindong; Zhou, Huandi; Huang, Fengming; Li, Chang; Lu, Huijun; Li, Ning; Li, Dangsheng; Jin, Ningyi; Penninger, Josef M; Jiang, Chengyu

    2014-05-06

    The potential for avian influenza H5N1 outbreaks has increased in recent years. Thus, it is paramount to develop novel strategies to alleviate death rates. Here we show that avian influenza A H5N1-infected patients exhibit markedly increased serum levels of angiotensin II. High serum levels of angiotensin II appear to be linked to the severity and lethality of infection, at least in some patients. In experimental mouse models, infection with highly pathogenic avian influenza A H5N1 virus results in downregulation of angiotensin-converting enzyme 2 (ACE2) expression in the lung and increased serum angiotensin II levels. Genetic inactivation of ACE2 causes severe lung injury in H5N1-challenged mice, confirming a role of ACE2 in H5N1-induced lung pathologies. Administration of recombinant human ACE2 ameliorates avian influenza H5N1 virus-induced lung injury in mice. Our data link H5N1 virus-induced acute lung failure to ACE2 and provide a potential treatment strategy to address future flu pandemics.

  20. Highly Pathogenic Avian Influenza H5N1 in Mainland China.

    Science.gov (United States)

    Li, Xin-Lou; Liu, Kun; Yao, Hong-Wu; Sun, Ye; Chen, Wan-Jun; Sun, Ruo-Xi; de Vlas, Sake J; Fang, Li-Qun; Cao, Wu-Chun

    2015-05-08

    Highly 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 the disease, including universal vaccination campaigns in poultry and active serological and virological surveillance, have been undertaken in mainland China since the beginning of 2006. In this study, we aim to characterize the spatial and temporal patterns of HPAI H5N1, and identify influencing factors favoring the occurrence of HPAI H5N1 outbreaks in poultry in mainland China. Our study shows that HPAI H5N1 outbreaks took place sporadically after vaccination campaigns in poultry, and mostly occurred in the cold season. The positive tests in routine virological surveillance of HPAI H5N1 virus in chicken, duck, goose as well as environmental samples were mapped to display the potential risk distribution of the virus. Southern China had a higher positive rate than northern China, and positive samples were mostly detected from chickens in the north, while the majority were from duck in the south, and a negative correlation with monthly vaccination rates in domestic poultry was found (R = -0.19, p value = 0.005). Multivariate panel logistic regression identified vaccination rate, interaction between distance to the nearest city and national highway, interaction between distance to the nearest lake and wetland, and density of human population, as well as the autoregressive term in space and time as independent risk factors in the occurrence of HPAI H5N1 outbreaks, based on which a predicted risk map of the disease was derived. Our findings could provide new understanding of the distribution and transmission of HPAI H5N1 in mainland China and could be used to inform targeted surveillance and control efforts in both human and poultry populations to reduce the risk of future infections.

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

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    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.

  2. Insights into Human Astrocyte Response to H5N1 Infection by Microarray Analysis

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    Xian Lin

    2015-05-01

    Full Text Available Influenza virus infects not only the respiratory system but also the central nervous system (CNS, leading to influenza-associated encephalopathy and encephalitis. Astrocytes are essential for brain homeostasis and neuronal function. These cells can also be infected by influenza virus. However, genome-wide changes in response to influenza viral infection in astrocytes have not been defined. In this study, we performed gene profiling of human astrocytes in response to H5N1. Innate immune and pro-inflammatory responses were strongly activated at 24 h post-infection (hpi. Antiviral genes, as well as several cytokines and chemokines, including CXCL9, CXCL10, and CXCL11, were robustly induced. Phosphorylation of p65 and p38 can be activated by viral infection, suggesting their potential critical roles in H5N1-induced pro-inflammatory response. Moreover, H5N1 infection significantly upregulated the gene expressions related to the neuroactive ligand-receptor interaction pathway at 24 hpi, such as MC2R, CHRNG, P2RY13, GABRA1, and HRH2, which participant in synaptic transmission and may take part in CNS disorders induced by H5N1 infection. Targeting key components of innate immune response and the neuroactive ligand-receptor interaction pathway may provide a strategy to control H5N1-induced encephalopathy and encephalitis. This research can contribute to the understanding of H5N1 pathogenesis in astrocytes.

  3. 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...

  4. Evaluation of the sublingual route for administration of influenza H5N1 virosomes in combination with the bacterial second messenger c-di-GMP.

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    Gabriel Kristian Pedersen

    Full Text Available Avian influenza A H5N1 is a virus with pandemic potential. Mucosal vaccines are attractive as they have the potential to block viruses at the site of entry, thereby preventing both disease and further transmission. The intranasal route is safe for the administration of seasonal live-attenuated influenza vaccines, but may be less suitable for administration of pandemic vaccines. Research into novel mucosal routes is therefore needed. In this study, a murine model was used to compare sublingual administration with intranasal and intramuscular administration of influenza H5N1 virosomes (2 µg haemagglutinin; HA in combination with the mucosal adjuvant (3',5'-cyclic dimeric guanylic acid (c-di-GMP. We found that sublingual immunisation effectively induced local and systemic H5N1-specific humoral and cellular immune responses but that the magnitude of response was lower than after intranasal administration. However, both the mucosal routes were superior to intramuscular immunisation for induction of local humoral and systemic cellular immune responses including high frequencies of splenic H5N1-specific multifunctional (IL-2+TNF-α+ CD4+ T cells. The c-di-GMP adjuvanted vaccine elicited systemic haemagglutination inhibition (HI antibody responses (geometric mean titres ≥ 40 both when administered sublingually, intranasally and inramuscularly. In addition, salivary HI antibodies were elicited by mucosal, but not intramuscular vaccination. We conclude that the sublingual route is an attractive alternative for administration of pandemic influenza vaccines.

  5. Evaluation of the sublingual route for administration of influenza H5N1 virosomes in combination with the bacterial second messenger c-di-GMP.

    Science.gov (United States)

    Pedersen, Gabriel Kristian; Ebensen, Thomas; Gjeraker, Ingrid Hjetland; Svindland, Signe; Bredholt, Geir; Guzmán, Carlos Alberto; Cox, Rebecca Jane

    2011-01-01

    Avian influenza A H5N1 is a virus with pandemic potential. Mucosal vaccines are attractive as they have the potential to block viruses at the site of entry, thereby preventing both disease and further transmission. The intranasal route is safe for the administration of seasonal live-attenuated influenza vaccines, but may be less suitable for administration of pandemic vaccines. Research into novel mucosal routes is therefore needed. In this study, a murine model was used to compare sublingual administration with intranasal and intramuscular administration of influenza H5N1 virosomes (2 µg haemagglutinin; HA) in combination with the mucosal adjuvant (3',5')-cyclic dimeric guanylic acid (c-di-GMP). We found that sublingual immunisation effectively induced local and systemic H5N1-specific humoral and cellular immune responses but that the magnitude of response was lower than after intranasal administration. However, both the mucosal routes were superior to intramuscular immunisation for induction of local humoral and systemic cellular immune responses including high frequencies of splenic H5N1-specific multifunctional (IL-2+TNF-α+) CD4+ T cells. The c-di-GMP adjuvanted vaccine elicited systemic haemagglutination inhibition (HI) antibody responses (geometric mean titres ≥ 40) both when administered sublingually, intranasally and inramuscularly. In addition, salivary HI antibodies were elicited by mucosal, but not intramuscular vaccination. We conclude that the sublingual route is an attractive alternative for administration of pandemic influenza vaccines.

  6. Avian Influenza A(H5N1) Virus in Egypt.

    Science.gov (United States)

    Kayali, Ghazi; Kandeil, Ahmed; El-Shesheny, Rabeh; Kayed, Ahmed S; Maatouq, Asmaa M; Cai, Zhipeng; McKenzie, Pamela P; Webby, Richard J; El Refaey, Samir; Kandeel, Amr; Ali, Mohamed A

    2016-03-01

    In Egypt, avian influenza A subtype H5N1 and H9N2 viruses are enzootic in poultry. The control plan devised by veterinary authorities in Egypt to prevent infections in poultry focused mainly on vaccination and ultimately failed. Recently, widespread H5N1 infections in poultry and a substantial increase in the number of human cases of H5N1 infection were observed. We summarize surveillance data from 2009 through 2014 and show that avian influenza viruses are established in poultry in Egypt and are continuously evolving genetically and antigenically. We also discuss the epidemiology of human infection with avian influenza in Egypt and describe how the true burden of disease is underestimated. We discuss the failures of relying on vaccinating poultry as the sole intervention tool. We conclude by highlighting the key components that need to be included in a new strategy to control avian influenza infections in poultry and humans in Egypt.

  7. Cross-reactive neuraminidase antibodies afford partial protection against H5N1 in mice and are present in unexposed humans.

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    Matthew R Sandbulte

    2007-02-01

    Full Text Available BACKGROUND: A pandemic H5N1 influenza outbreak would be facilitated by an absence of immunity to the avian-derived virus in the human population. Although this condition is likely in regard to hemagglutinin-mediated immunity, the neuraminidase (NA of H5N1 viruses (avN1 and of endemic human H1N1 viruses (huN1 are classified in the same serotype. We hypothesized that an immune response to huN1 could mediate cross-protection against H5N1 influenza virus infection. METHODS AND FINDINGS: Mice were immunized against the NA of a contemporary human H1N1 strain by DNA vaccination. They were challenged with recombinant A/Puerto Rico/8/34 (PR8 viruses bearing huN1 (PR8-huN1 or avN1 (PR8-avN1 or with H5N1 virus A/Vietnam/1203/04. Additional naïve mice were injected with sera from vaccinated mice prior to H5N1 challenge. Also, serum specimens from humans were analyzed for reactivity with avN1. Immunization elicited a serum IgG response to huN1 and robust protection against the homologous challenge virus. Immunized mice were partially protected from lethal challenge with H5N1 virus or recombinant PR8-avN1. Sera transferred from immunized mice to naïve animals conferred similar protection against H5N1 mortality. Analysis of human sera showed that antibodies able to inhibit the sialidase activity of avN1 exist in some individuals. CONCLUSIONS: These data reveal that humoral immunity elicited by huN1 can partially protect against H5N1 infection in a mammalian host. Our results suggest that a portion of the human population could have some degree of resistance to H5N1 influenza, with the possibility that this could be induced or enhanced through immunization with seasonal influenza vaccines.

  8. Evolution of highly pathogenic avian influenza H5N1 viruses in Egypt indicating progressive adaptation

    Science.gov (United States)

    Highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype was first diagnosed in poultry in Egypt in 2006, and since then the disease became enzootic in poultry throughout the country affecting the poultry industry and village poultry as well as infecting humans. Vaccination has been used ...

  9. Widespread of H5N1 infections in apparently healthy backyard poultry.

    Science.gov (United States)

    Abozaid, Khaled G A; Aly, Mona M; Abdel-Moneim, Ahmed S; El-Kady, Magdy F

    2016-08-01

    Highly pathogenic avian influenza subtype H5N1 represents a threat to the poultry industry and human health worldwide. Inapparently infected birds are suspected to play an essential role in the spread of avian influenza virus. In the current study, a total of 25,646 samples (16,185 chicken, 4696 ducks, 1633 geese and 3132 turkeys) from apparently healthy birds were screened for the presence of positive samples for H5N1 during 2009-2014. The samples were examined by reverse transcriptase real-time polymerase chain reaction (rRT-PCR) for M, H5 and N1 genes of avian influenza viruses. The results revealed that the HPAI H5N1 existed in an inapparent manner in ducks (4.68 %), geese (4.10 %), chickens (2.48 %) and turkeys (2.29 %). The current finding highlights the serious impact of such type on birds in the epidemiology of H5N1 in birds, animals and humans. It also highlights the existence of another reason other than vaccination that contributes to the widespread of inapparent infection of H5N1 in Egypt.

  10. Application of Baculovirus Dual Expression System in the Prevention of H5N1 Avian Influenza Virus%H5N1亚型禽流感病毒HA基因杆状病毒双表达系统的构建及其在小鼠的免疫原性分析

    Institute of Scientific and Technical Information of China (English)

    樊惠英; 林文耀; 佟铁铸; 张杰; 叶昱; 靳立明; 张春雷; 廖明

    2013-01-01

    Avian influenza is one of the deadly infectious diseases of poultry, which influences the development of agricultural economy of China greatly. Highly pathogenic avian influenza (HPAI) virus like H5N1 can even break the species barrier and infect human, which may pose great threat to public health. Currently, inactivated vaccines are the main vaccine in preventing avian influenza, which may accelerate virus transmission if we can't get the virus completely inactivated. Therefore, we need safer and more effective vaccines. In this study, we constructed a recombi-nant baculovirus BV-G-H5N1-HA, expressing HA protein in mammalian cell and exhibiting HA protein on the surface of the viral envelope simultaneously. Animal experiment was conducted by vaccinating mice intramuscularly with BV-G-H5N1-HA, pc-H5N1-HA, AcMNPV WT (wild-type AcMNPV) and PBS, respectively, then the mice were challenged intranasally (i. n. ) with A/Chicken/Guangzhou/M/2008(H5N1). Results showed that BV-G-H5N1l-HA can induce higher concentrations of neutralizing antibody and HI antibody in the immune group, and provide a considerable protection rate of 91. 7%. All these data indicate that BV-G-H5N1-HA may be a novel vaccine candidate which helps to prevent and control of HPAI in the future. Moreover, the application of novel baculovirus vector will provide important insights into the field of animal vaccine development.%高致病性禽流感严重制约着禽类产业链的健康发展,以H5N1为代表的高致病性禽流感病毒能够跨越种间障碍感染人,对公共卫生安全造成极大危害.而预防禽流感的传统疫苗主要是全病毒灭活苗,该类疫苗使用量大,灭活不全时易造成散毒,并给流行病学监测带来困难.研发更加安全、高效的新型疫苗势在必行.本研究选取H5N1亚型流感病毒的HA蛋白作为靶抗原,构建重组杆状病毒BV-G-H5N1-HA.重组病毒本身可刺激机体天然免疫反应,通过基因改造一方面能在真核

  11. DNA prime and virus-like particle boost from a single H5N1 strain elicits broadly neutralizing antibody responses against head region of H5 hemagglutinin.

    Science.gov (United States)

    Wang, Guiqin; Zhou, Fan; Buchy, Philippe; Zuo, Teng; Hu, Hongxing; Liu, Jingjing; Song, Yufeng; Ding, Heng; Tsai, Cheguo; Chen, Ze; Zhang, Linqi; Deubel, Vincent; Zhou, Paul

    2014-03-01

    Since 1996, highly pathogenic avian influenza (HPAI) H5N1 virus has presented a persistent threat to public health. Its high degree of genetic diversity also poses enormous challenges in developing effective vaccines. To search for vaccine regimens that could elicit broadly neutralizing antibody responses against diverse HPAI H5N1 strains, in the present study we tested H5 hemagglutinin (HA) from an A/Thailand/1(KAN)-1/2004 strain in a heterologous prime-boost vaccination. We demonstrated that priming mice with DNA and boosting with virus-like particle induced antibody responses that cross-neutralize all reported clades and subclades of HPAI H5N1 viruses and protect mice from high lethal dose HPAI H5N1 challenge in both active and passive immunizations. Unexpectedly, cross-divergent H5 neutralizing antibodies are directed to the HA head and block both attachment and postattachment of virus entry. Thus, we conclude that as a promising pan-H5 vaccine candidate this prime-boost regimen could be further developed in ferrets and in humans.

  12. Glycan masking of hemagglutinin for adenovirus vector and recombinant protein immunizations elicits broadly neutralizing antibodies against H5N1 avian influenza viruses.

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    Shih-Chang Lin

    Full Text Available The highly pathogenic avian influenza (HPAI H5N1 virus, a known trigger of diseases in poultry and humans, is perceived as a serious threat to public health. There is a clear need for a broadly protective H5N1 vaccine or vaccines for inducing neutralizing antibodies against multiple clades/subclades. We constructed single, double, and triple mutants of glycan-masked hemagglutiinin (HA antigens at residues 83, 127 and 138 (i.e., g83, g127, g138, g83+g127, g127+g138, g83+g138 and g83+g127+g138, and then obtained their corresponding HA-expressing adenovirus vectors and recombinant HA proteins using a prime-boost immunization strategy. Our results indicate that the glycan-masked g127+g138 double mutant induced more potent HA-inhibition, virus neutralization antibodies, cross-clade protection against heterologous H5N1 clades, correlated with the enhanced bindings to the receptor binding sites and the highly conserved stem region of HA. The immune refocusing stem-specific antibodies elicited by the glycan-masked H5HA g127+g138 and g83+g127+g138 mutants overlapped with broadly neutralizing epitopes of the CR6261 monoclonal antibody that neutralizes most group 1 subtypes. These findings may provide useful information in the development of a broadly protective H5N1 influenza vaccine.

  13. Cross-clade protective immune responses to influenza viruses with H5N1 HA and NA elicited by an influenza virus-like particle.

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    Rick A Bright

    Full Text Available BACKGROUND: Vaccination is a cost-effective counter-measure to the threat of seasonal or pandemic outbreaks of influenza. To address the need for improved influenza vaccines and alternatives to egg-based manufacturing, we have engineered an influenza virus-like particle (VLP as a new generation of non-egg or non-mammalian cell culture-based candidate vaccine. METHODOLOGY/PRINCIPAL FINDINGS: We generated from a baculovirus expression system using insect cells, a non-infectious recombinant VLP vaccine from both influenza A H5N1 clade 1 and clade 2 isolates with pandemic potential. VLPs were administered to mice in either a one-dose or two-dose regimen and the immune responses were compared to those induced by recombinant hemagglutinin (rHA. Both humoral and cellular responses were analyzed. Mice vaccinated with VLPs were protected against challenge with lethal reassortant viruses expressing the H5N1 HA and NA, regardless if the H5N1 clade was homologous or heterologous to the vaccine. However, rHA-vaccinated mice showed considerable weight loss and death following challenge with the heterovariant clade virus. Protection against death induced by VLPs was independent of the pre-challenge HAI titer or cell-mediated responses to HA or M1 since vaccinated mice, with low to undetectable cross-clade HAI antibodies or cellular responses to influenza antigens, were still protected from a lethal viral challenge. However, an apparent association rate of antibody binding to HA correlated with protection and was enhanced using VLPs, particularly when delivered intranasally, compared to rHA vaccines. CONCLUSION/SIGNIFICANCE: This is the first report describing the use of an H5N1 VLP vaccine created from a clade 2 isolate. The results show that a non-replicating virus-like particle is effective at eliciting a broadened, cross-clade protective immune response to proteins from emerging H5N1 influenza isolates giving rise to a potential pandemic influenza vaccine

  14. 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.

  15. The preliminary screening of different adjuvants in transcutaneous immunization with inactivated human highly pathogenic avian influenza vaccine%高致病性人禽流感H5N1透皮疫苗免疫佐剂的初步筛选

    Institute of Scientific and Technical Information of China (English)

    孙艳丽; 孙艳花; 马安伦; 鹿文葆; 陈惠方; 王希良

    2009-01-01

    To screen the potent adjuvants used in transcutaneous immunization with inactivated highly pathogenic avian influenza vaccine, four different adjuvants, CT, CpGODN1826, CpG ODN2006 and MF59, were used to immunize BALB/c mice together with this kind of vaccine in different proportions by transcutaneous immunization route and sera were collected before the first transcutaneous immunization and every two weeks post immunization. The titers of influenza virus-specific humoral IgG, and IgA were assayed in serum, lung and nasal lavages by ELISA. The titers of hemagglutination inhibition (HAD and IFN-7 and IL-4 produced by splenic lymphocytes were also detected. Our data showed that serum IgG titers and HAI titers in the groups of CpG1826 + HA, CT+HA and CpG1826 + CT+HA were significantly higher than those of HA group (P<0. 05) , particularly, in CpG1826 + CT+HA group. In addition, the influenza virus-specific IgA and IgG were detected in the lung and nasal lavages. Furthermore, the numbers of splenic lymphocytes producing IFN-γ and IL-4 were increased in mice after vaccination with inactivated highly pathogenic avian influenza combined with different adjuvants in comparison with those in control groups. Our result of study indicates that CpG ODN and cholera toxin are potent trancutaneous adjuvants in mouse model inoculated with inactivated high pathogenic avian influenza vaccine, and both of them can induce Th1 and Th2 cytokine production and mucosal immune responses.%用不同的佐剂与高致病性人禽流感H5N1全病毒疫苗混合,通过透皮途径免疫BALB/c小鼠并评价其免疫应答效果,从而初步筛选出较好的透皮免疫佐剂.实验选用CT、CPG 0DN1826、CpG ODN2006、MF59四种不同的佐剂按适当的比例与高致病性人禽流感H5N1灭活全病毒抗原混合制成透皮疫苗,透皮免疫BALB/c小鼠,检测血清IgG抗体效价、血清中和抗体效价,以及肺、鼻灌洗液中特异性IgG和IgA抗体效价,并对脾淋

  16. Highly Pathogenic Avian Influenza H5N1 in Mainland China

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    Xin-Lou Li

    2015-05-01

    Full Text Available Highly 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 the disease, including universal vaccination campaigns in poultry and active serological and virological surveillance, have been undertaken in mainland China since the beginning of 2006. In this study, we aim to characterize the spatial and temporal patterns of HPAI H5N1, and identify influencing factors favoring the occurrence of HPAI H5N1 outbreaks in poultry in mainland China. Our study shows that HPAI H5N1 outbreaks took place sporadically after vaccination campaigns in poultry, and mostly occurred in the cold season. The positive tests in routine virological surveillance of HPAI H5N1 virus in chicken, duck, goose as well as environmental samples were mapped to display the potential risk distribution of the virus. Southern China had a higher positive rate than northern China, and positive samples were mostly detected from chickens in the north, while the majority were from duck in the south, and a negative correlation with monthly vaccination rates in domestic poultry was found (R = −0.19, p value = 0.005. Multivariate panel logistic regression identified vaccination rate, interaction between distance to the nearest city and national highway, interaction between distance to the nearest lake and wetland, and density of human population, as well as the autoregressive term in space and time as independent risk factors in the occurrence of HPAI H5N1 outbreaks, based on which a predicted risk map of the disease was derived. Our findings could provide new understanding of the distribution and transmission of HPAI H5N1 in mainland China and could be used to inform targeted surveillance and control efforts in both human and poultry populations to reduce the risk of

  17. Influenza viruses and the evolution of avian influenza virus H5N1.

    Science.gov (United States)

    Skeik, Nedaa; Jabr, Fadi I

    2008-05-01

    Although small in size and simple in structure, influenza viruses are sophisticated organisms with highly mutagenic genomes and wide antigenic diversity. They are species-specific organisms. Mutation and reassortment have resulted in newer viruses such as H5N1, with new resistance against anti-viral medications, and this might lead to the emergence of a fully transmissible strain, as occurred in the 1957 and 1968 pandemics. Influenza viruses are no longer just a cause of self-limited upper respiratory tract infections; the H5N1 avian influenza virus can cause severe human infection with a mortality rate exceeding 50%. The case death rate of H5N1 avian influenza infection is 20 times higher than that of the 1918 infection (50% versus 2.5%), which killed 675000 people in the USA and almost 40 million people worldwide. While the clock is still ticking towards what seems to be inevitable pandemic influenza, on April 17, 2007 the U.S. Food and Drug Administration (FDA) approved the first vaccine against the avian influenza virus H5N1 for humans at high risk. However, more research is needed to develop a more effective and affordable vaccine that can be given at lower doses.

  18. 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

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

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    Sang-Moo Kang

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: These results provide support for clinical evaluation of H5N1 VLP vaccination as a public health intervention to mitigate a possible pandemic of H5N1 influenza.

  20. Epitope mapping of neutralizing monoclonal antibody in avian influenza A H5N1 virus hemagglutinin.

    Science.gov (United States)

    Ohkura, Takashi; Kikuchi, Yuji; Kono, Naoko; Itamura, Shigeyuki; Komase, Katsuhiro; Momose, Fumitaka; Morikawa, Yuko

    2012-02-03

    The global spread of highly pathogenic avian influenza A H5N1 viruses raises concerns about more widespread infection in the human population. Pre-pandemic vaccine for H5N1 clade 1 influenza viruses has been produced from the A/Viet Nam/1194/2004 strain (VN1194), but recent prevalent avian H5N1 viruses have been categorized into the clade 2 strains, which are antigenically distinct from the pre-pandemic vaccine. To understand the antigenicity of H5N1 hemagglutinin (HA), we produced a neutralizing monoclonal antibody (mAb12-1G6) using the pre-pandemic vaccine. Analysis with chimeric and point mutant HAs revealed that mAb12-1G6 bound to the loop (amino acid positions 140-145) corresponding to an antigenic site A in the H3 HA. mAb12-1G6 failed to bind to the mutant VN1194 HA when only 3 residues were substituted with the corresponding residues of the clade 2.1.3.2 A/Indonesia/5/05 strain (amino acid substitutions at positions Q142L, K144S, and S145P), suggesting that these amino acids are critical for binding of mAb12-1G6. Escape mutants of VN1194 selected with mAb12-1G6 carried a S145P mutation. Interestingly, mAb12-1G6 cross-neutralized clade 1 and clade 2.2.1 but not clade 2.1.3.2 or clade 2.3.4 of the H5N1 virus. We discuss the cross-reactivity, based on the amino acid sequence of the epitope.

  1. H5N1禽流感文献计量与可视化分析%Metrology and visualized analysis of H5N1 virus:a research of literature

    Institute of Scientific and Technical Information of China (English)

    陈婷; 吴曙霞; 盛立; 刘伟; 刁天喜

    2015-01-01

    目的:对国内外H5N1禽流感研究文献进行文献计量及可视化知识图谱分析。方法基于Web of Knowledge文献数据平台(SCI),综合应用Bibexcel、VOSviewer和Pajek等软件,展示全球H5N1禽流感研究的主要领域和前沿。结果从文献分析结果来看,全球H5 N1禽流感研究从2005年开始持续多年处于高水平态势,美国在这一领域处于领先地位,中国紧随其后。结论 H5 N1禽流感文献计量可视化分析显示,全球多国科学家常年都十分重视H5 N1禽流感研究,美国H5 N1禽流感研究整体实力最强,我国与国际相关研究机构还有一定差距,因此,应加强H5 N1禽流感研究,提高我国H5 N1禽流感研究整体实力水平,为应对可能发生的公共卫生突发事件提供必要的保障。%Objective To analyze domestic and foreign papers on H5N1 virus research using literature metrology and visualized knowledge mapping.Methods Pajek, Bibexcel,and VoSviewer software were used based on Web of Knowledge platform.Results Study on H5N1 virus has been a research focus wide since 2005 and a series of institutions and investi-gators have appeared, with US being the leader in this area and followed by China.The most popular topics of studies on H5N1 included its virology, epidemiology, basic research, anti-virus drugs and vaccines.Conclusion Studies on H5N1 have received more attention, which suggests that more efforts have to be made in China in terms of communication and co-operation with key institutions and famous researchers so as to achieve more success in key areas.

  2. Immunostimulatory motifs enhance antiviral siRNAs targeting highly pathogenic avian influenza H5N1.

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    Cameron R Stewart

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 virus is endemic in many regions around the world and remains a significant pandemic threat. To date H5N1 has claimed almost 300 human lives worldwide, with a mortality rate of 60% and has caused the death or culling of hundreds of millions of poultry since its initial outbreak in 1997. We have designed multi-functional RNA interference (RNAi-based therapeutics targeting H5N1 that degrade viral mRNA via the RNAi pathway while at the same time augmenting the host antiviral response by inducing host type I interferon (IFN production. Moreover, we have identified two factors critical for maximising the immunostimulatory properties of short interfering (siRNAs in chicken cells (i mode of synthesis and (ii nucleoside sequence to augment the response to virus. The 5-bp nucleoside sequence 5'-UGUGU-3' is a key determinant in inducing high levels of expression of IFN-α, -β, -λ and interleukin 1-β in chicken cells. Positioning of this 5'-UGUGU-3' motif at the 5'-end of the sense strand of siRNAs, but not the 3'-end, resulted in a rapid and enhanced induction of type I IFN. An anti-H5N1 avian influenza siRNA directed against the PB1 gene (PB1-2257 tagged with 5'-UGUGU-3' induced type I IFN earlier and to a greater extent compared to a non-tagged PB1-2257. Tested against H5N1 in vitro, the tagged PB1-2257 was more effective than non-tagged PB1-2257. These data demonstrate the ability of an immunostimulatory motif to improve the performance of an RNAi-based antiviral, a finding that may influence the design of future RNAi-based anti-influenza therapeutics.

  3. Avian influenza H5N1: an update on molecular pathogenesis

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Avian influenza A virus constitutes a large threat to human health. Recent outbreaks of highly pathogenic avian influenza H5N1 virus in poultry and in humans have raised concerns that an influenza pandemic will occur in the near future. Transmission from avian species to humans remains sporadic, but the mortality associated with human infection is very high (about 62%). To date, there are no effective therapeutic drugs or a prophylactic vaccines available, which means that there is still a long way to go before we can eradicate or cure avian influenza. This review focuses on the molecular pathogenesis of avian influenza H5N1 virus infection. An understanding of the viral pathogenesis may facilitate the development of novel treatments or effective eradication of this fatal disease.

  4. Avian influenza H5N1: an update on molecular pathogenesis

    Institute of Scientific and Technical Information of China (English)

    WANG HongLiang; JIANG ChengYu

    2009-01-01

    Avian influenza A virus constitutes a large threat to human health. Recent outbreaks of highly patho-genic avian influenza H5N1 virus in poultry and in humans have raised concerns that an influenza pandemic will occur in the near future. Transmission from avian species to humans remains sporadic, but the mortality associated with human infection is very high (about 62%). To date, there are no effec-tive therapeutic drugs or a prophylactic vaccines available, which means that there is still a long way to go before we can eradicate or cure avian influenza. This review focuses on the molecular pathogenesis of avian influenza H5N1 virus infection. An understanding of the viral pathogenesis may facilitate the development of novel treatments or effective eradication of this fatal disease.

  5. 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

    data suggests that viremia, secondary to, for example, gastro-intestinal infection, can potentially lead to infection of the lung. HPAI H5N1 virus was a more potent inducer of cytokines (e.g. IP-10, RANTES, IL-6 in comparison to H1N1 virus in alveolar epithelial cells, and these virus-induced chemokines were secreted onto both the apical and basolateral aspects of the polarized alveolar epithelium. Conclusion The predilection of viruses for different routes of entry and egress from the infected cell is important in understanding the pathogenesis of influenza H5N1 infection and may help unravel the pathogenesis of human H5N1 disease.

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

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    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.

  7. 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.

  8. Influenza A virus H5N1 entry into host cells is through clathrin-dependent endocytosis

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Influenza A virus H5N1 presents a major threat to human health. The entry of influenza virus into host cells is believed to be mediated by hemagglutinin (HA), a virus surface glycoprotein that can bind terminal sialic acid residues on host cell glycoproteins and glycolipids. In this study, we elucidated the pathways through which H5N1 enters human lung carcinoma cell line A549. We first proved that H5N1 can enter A549 cells via endocytosis, as lysosomotropic agents, such as bafilomycin A1 and chloroquine, can rescue H5N1-induced A549 cell death. By using specific inhibitors, and siRNAs that target the clathrin pathway, we further found that H5N1 could enter A549 cells via clathrin-mediated endocytosis, while inhibitors targeting caveolae-mediated endocytosis could not inhibit H5N1 cell entry. These findings expand our understanding of H5N1 pathogenesis and provide new information for anti-viral drug research.

  9. Prevention and control of highly pathogenic avian influenza with particular reference to H5N1.

    Science.gov (United States)

    Capua, Ilaria; Cattoli, Giovanni

    2013-12-05

    Highly pathogenic avian influenza viruses of the H5N1 subtype emerged in Far East Asia in 1996 and spread in three continents in a period of 10 or less years. Before this event, avian influenza infections caused by highly pathogenic viruses had occurred in many different countries, causing minor or major outbreaks, and had always been eradicated. The unique features of these H5N1 viruses combined to the geographic characteristics of the area of emergence, including animal husbandry practices, has caused this subtype to become endemic in several Asian countries, as well as in Egypt. Our aim is to review the direct and indirect control strategies with the rationale for use, advantages and shortcomings - particularly resulting from practicalities linked to field application and economic constraints. Certainly, in low income countries which have applied vaccination, this has resulted in a failure to eradicate the infection. Although the number of infected countries has dropped from over 40 (2006) to under 10 (2012), the extensive circulation of H5N1 in areas with high poultry density still represents a risk for public and animal health.

  10. Pathogenicity of human high pathogenic H5N1 virus with different plaque property

    Directory of Open Access Journals (Sweden)

    Yong-qiang LI

    2011-06-01

    Full Text Available Objective To determine the pathogenicity of human high pathogenic H5N1 virus with different plaque property,and provide a new train of thought and basis for research on crossing species-genus transmission of avian influenza virus.Methods Variants with different plaque property(larger-and smaller-plaque variant were isolated from A/Beijing/01/03(H5N1(BJ01 by the plaque purification.Mice were inoculated intranasally(i.n. with each kind of isolated variant and monitored for 14 days to record and calculate the body weight change and the survival rate.The difference in pathogenicity of isolated variants was estimated with proper principle of statistics.Results The plaques of original strain of BJ01 virus were heterogeneous with various size and shape.Larger-plaque variants(L1 and L2 and smaller-plaque variants(S1,S2 and S3 were isolated separately.The pathogenicity was higher in S1 and S2 variants than in S3,L1 and L2 variants,and that of L2 variant was the lowest.Variants forming different plaques were heterogeneous in pathogenicity,and those forming same plaques were also heterogeneous in pathogenicity.Conclusion There is no linear correlation between the pathogenicity of variants and the size of plaque they formed.The variants with different pathogenicity could be isolated from the same H5N1 virus strain by plaque purification.These results would provide a basis for vaccine development and the studies on molecular mechanism of H5N1 virus.

  11. High interferon type I responses in the lung, plasma and spleen during highly pathogenic H5N1 infection of chicken

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    Moulin Hervé R

    2011-01-01

    Full Text Available Abstract This study shows that high pathogenic H5N1 influenza virus infection of chicken induced high levels of bioactive interferon type I in the lung (4.3 × 105 U/mg tissue, plasma (1.1 × 105 U/mL, and spleen (9.1 × 105 U/mg tissue. In contrast, a low pathogenic attenuated H5N1 vaccine strain only induced approximately 24 times less IFN in the lung, 441 times less in the spleen and 649 less in the plasma. This was in the same range as a reassortant carrying the HA from the vaccine strain and the remaining genes from the high pathogenic virus. On the other hand, a reassortant virus with the HA from the high pathogenic H5N1 with the remaining genes from the vaccine strain had intermediate levels of IFN. The level of interferon responses related to the viral load, and those in the spleen and blood to the spread of virus to lymphoid tissue, as well as disease severity. In vitro, the viruses did not induce interferon in chicken embryonic fibroblasts, but high levels in splenocytes, with not clear relationship to pathogenicity and virulence. This, and the responses also with inactivated viruses imply the presence of plasmacytoid dendritic cell-like leukocytes within the chicken immune system, possibly responsible for the high interferon responses during H5N1 infection. Our data also indicate that the viral load as well as the cleavability of the HA enabling systemic spread of the virus are two major factors controlling systemic IFN responses in chicken.

  12. Purification of neuraminidase from Influenza virus subtype H5N1

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    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.

  13. Influenza H5N1 Virus of Birds Surrounding H5N1 Human Cases Have Specific Characteristics on the Matrix Protein

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    NI LUH PUTU INDI DHARMAYANTI

    2011-06-01

    Full Text Available The H5N1 influenza virus in Indonesia has caused more than 100 people died due to the virus infections. Cases in humans were mostly due to the virus spread from the infected birds. This study characterized molecularly the H5N1 virus from birds around the H5N1 infection cases in humans in Indonesia. Result from this study revealed that in several cases, waterfowl species could become the source of H5N1 infections in human. We found that the one of six viruses used in this study probably was a first antigenic shift virus in Indonesia. This study shows that the AI viruses isolated from birds around humans infected by H5N1 virus has specific characteristics namely the presence of several amino acid substitutions especially on the M1 and M2 proteins. The substitutions are similar in most of H5N1 human cases in Indonesia.

  14. Recombinant human interferon reduces titer of the 1918 pandemic and H5N1 influenza viruses in a guinea pig model

    Science.gov (United States)

    Although H5N1 subtype influenza viruses have yet to acquire the ability to transmit efficiently among humans, the geographic expansion, genetic diversity and persistence of H5N1 viruses in birds indicates that pandemic potential of these viruses remains high. Vaccination remains the primary means f...

  15. Characterization of H5N1 influenza viruses isolated from humans in vitro

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    Kameoka Masanori

    2010-06-01

    Full Text Available Abstract Since December 1997, highly pathogenic avian influenza A H5N1viruses have swept through poultry populations across Asian countries and been transmitted into African and European countries. We characterized 6 avian influenza H5N1 viruses isolated from humans in 2004 in Thailand. A highly pathogenic (HP KAN353 strain showed faster replication and higher virulence in embryonated eggs compared to other strains, especially compared to the low pathogenic (LP SP83 strain. HP KAN353 also showed strong cytopathogenicity compared to SP83 in Madin-Darby canine kidney cells. Interestingly, LP SP83 induced smaller plaques compared to other strains, especially HP KAN353. PB2 amino acid 627E may contribute to low virulence, whereas either PB2 amino acid 627 K or the combination of 627E/701N seems to be associated with high virulence. The in vitro assays used in this study may provide the basis for assessing the pathogenesis of influenza H5N1 viruses in vivo.

  16. Immune escape mutants of Highly Pathogenic Avian Influenza H5N1 selected using polyclonal sera: identification of key amino acids in the HA protein.

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    Ioannis Sitaras

    Full Text Available Evolution of Avian Influenza (AI viruses--especially of the Highly Pathogenic Avian Influenza (HPAI H5N1 subtype--is a major issue for the poultry industry. HPAI H5N1 epidemics are associated with huge economic losses and are sometimes connected to human morbidity and mortality. Vaccination (either as a preventive measure or as a means to control outbreaks is an approach that splits the scientific community, due to the risk of it being a potential driving force in HPAI evolution through the selection of mutants able to escape vaccination-induced immunity. It is therefore essential to study how mutations are selected due to immune pressure. To this effect, we performed an in vitro selection of mutants from HPAI A/turkey/Turkey/1/05 (H5N1, using immune pressure from homologous polyclonal sera. After 42 rounds of selection, we identified 5 amino acid substitutions in the Haemagglutinin (HA protein, most of which were located in areas of antigenic importance and suspected to be prone to selection pressure. We report that most of the mutations took place early in the selection process. Finally, our antigenic cartography studies showed that the antigenic distance between the selected isolates and their parent strain increased with passage number.

  17. Influenza A virus H5N1 entry into host cells is through clathrin-dependent endocytosis

    Institute of Scientific and Technical Information of China (English)

    WANG HongLiang; JIANG ChengYu

    2009-01-01

    Influenza A virus H5N1 presents a major threat to human health. The entry of influenza virus into host cells is believed to be mediated by hemagglutinin (HA), a virus surface glycoprotein that can bind ter-minal sialic acid residues on host cell glycoproteins and glycolipids. In this study, we elucidated the pathways through which H5N1 enters human lung carcinoma cell line A549. We first proved that H5N1 can enter A549 cells via endocytosis, as lysosomotropic agents, such as bafilomycin A1 and chloro. quine, can rescue H5Nl-induced A549 cell death. By using specific inhibitors, and siRNAs that target the clathrin pathway, we further found that H5N1 could enter A549 cells via clathrin-mediated endocy-tosis, while inhibitors targeting caveolae-mediated endocytosis could not inhibit H5N1 cell entry. These findings expand our understanding of H5N1 pathogenesis and provide new information for anti-viral drug research.

  18. The epitope and neutralization mechanism of AVFluIgG01, a broad-reactive human monoclonal antibody against H5N1 influenza virus.

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    Zhiliang Cao

    Full Text Available The continued spread of highly pathogenic avian influenza (HPAI H5N1 virus underscores the importance of effective antiviral approaches. AVFluIgG01 is a potent and broad-reactive H5N1-neutralizing human monoclonal antibody (mAb showing great potential for use either for therapeutic purposes or as a basis of vaccine development, but its antigenic epitope and neutralization mechanism have not been finely characterized. In this study, we first demonstrated that AVFluIgG01 targets a novel conformation-dependent epitope in the globular head region of H5N1 hemagglutinin (HA. By selecting mimotopes from a random peptide library in combination with computational algorithms and site-directed mutagenesis, the epitope was mapped to three conserved discontinuous sites (I-III that are located closely at the three-dimensional structure of HA. Further, we found that this HA1-specific human mAb can efficiently block both virus-receptor binding and post-attachment steps, while its Fab fragment exerts the post-attachment inhibition only. Consistently, AVFluIgG01 could inhibit HA-mediated cell-cell membrane fusion at a dose-dependent manner and block the acquisition of pH-induced protease sensitivity. These results suggest a neutralization mechanism of AVFluIgG01 by simultaneously blocking viral attachment to the receptors on host cells and interfering with HA conformational rearrangements associated with membrane fusion. The presented data provide critical information for developing novel antiviral therapeutics and vaccines against HPAI H5N1 virus.

  19. Antigenicity and transmissibility of a novel clade 2.3.2.1 avian influenza H5N1 virus.

    Science.gov (United States)

    Xu, Lili; Bao, Linlin; Yuan, Jing; Li, Fengdi; Lv, Qi; Deng, Wei; Xu, Yanfeng; Yao, Yanfeng; Yu, Pin; Chen, Honglin; Yuen, Kwok-Yung; Qin, Chuan

    2013-12-01

    A genetic variant of the H5N1 influenza virus, termed subclade 2.3.2.1, was first identified in Bulgaria in 2010 and has subsequently been found in Vietnam and Laos. Several cases of human infections with this virus have been identified. Thus, it is important to understand the antigenic properties and transmissibility of this variant. Our results showed that, although it is phylogenetically closely related to other previously characterized clade 2.3 viruses, this novel 2.3.2.1 variant exhibited distinct antigenic properties and showed little cross-reactivity to sera raised against other H5N1 viruses. Like other H5N1 viruses, this variant bound preferentially to avian-type receptors, but contained substitutions at positions 190 and 158 of the haemagglutinin (HA) protein that have been postulated to facilitate HA binding to human-type receptors and to enhance viral transmissibility among mammals, respectively. However, this virus did not appear to have acquired the capacity for airborne transmission between ferrets. These findings highlight the challenges in selecting vaccine candidates for H5N1 influenza because these viruses continue to evolve rapidly in the field. It is important to note that some variants have obtained mutations that may gain transmissibility between model animals, and close surveillance of H5N1 viruses in poultry is warranted.

  20. Avian Influenza (H5N1) Susceptibility and Receptors in Dogs

    OpenAIRE

    Maas,; Tacken, M.G.J.; Ruuls-van Stalle, E.M.F.; G. Koch; Rooij, De; Stockhofe-Zurwieden, N.

    2007-01-01

    Inoculation of influenza (H5N1) into beagles resulted in virus excretion and rapid seroconversion with no disease. Binding studies that used labeled influenza (H5N1) showed virus attachment to higher and lower respiratory tract tissues. Thus, dogs that are subclinically infected with influenza (H5N1) may contribute to virus spread.

  1. Avian flu : multiple introductions of H5N1 in Nigeria

    NARCIS (Netherlands)

    Ducatez, M F; Olinger, C M; Owoade, A A; De Landtsheer, S; Ammerlaan, W; Niesters, H G M; Osterhaus, A D M E; Fouchier, R A M; Muller, C P

    2006-01-01

    As the avian influenza virus H5N1 swept from Asia across Russia to Europe, Nigeria was the first country in Africa to report the emergence of this highly pathogenic virus. Here we analyse H5N1 sequences in poultry from two different farms in Lagos state and find that three H5N1 lineages were indepen

  2. 高致病性H5N1型禽流感%The overview of highly pathogenic H5N1 avian influenza

    Institute of Scientific and Technical Information of China (English)

    高维旭; 董芝

    2006-01-01

    目的:高致病性H5N1型禽流感在亚洲的持续爆发引起了人们对全球流感大流行的担心.截至2006年2月,已有160多人被证实感染了H5N1型禽流感,80多人已死亡.本文对H5N1型禽流感的起源,传播,预防及治疗,以及可能的流行情况进行了综述.

  3. Preparasi Imunoglobulin G Kelinci sebagai Antigen Penginduksi Antibodi Spesifik Terhadap Virus Avian Influenza H5N1 Strain Legok

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    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.

  4. 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.

  5. Role of Positive Selection Pressure on the Evolution of H5N1 Hemagglutinin

    Institute of Scientific and Technical Information of China (English)

    Venkata R.S.K. Duwuri; Bhargavi Duvvuri; Wilfred R. Cuff; Gillian E. Wu; Jianhong Wu

    2009-01-01

    The surface glycoprotein hemagglutinin (HA) helps the influenza A virus to evade the host immune system by antigenic variation and is a major driving force for viral evolution. In this study, the selection pressure on HA of H5N1 influenza A virus was analyzed using bioinformatics algorithms. Most of the identified positive selection (PS) sites were found to be within or adjacent to epitope sites. Some of the identified PS sites are consistent with previous experimental studies, providing further support to the biological significance of our findings. The highest frequency of PS sites was observed in recent strains isolated during 2005-2007. Phylogenetic analysis was also conducted on HA sequences from various hosts. Viral drift is almost similar in both avian and human species with a progressive trend over the years. Our study reports new mutations in functional regions of HA that might provide markers for vaccine design or can be used to predict isolates of pandemic potential.

  6. Comprehensive analysis of antibody recognition in convalescent humans from highly pathogenic avian influenza H5N1 infection.

    Science.gov (United States)

    Zuo, Teng; Sun, Jianfeng; Wang, Guiqin; Jiang, Liwei; Zuo, Yanan; Li, Danyang; Shi, Xuanling; Liu, Xi; Fan, Shilong; Ren, Huanhuan; Hu, Hongxing; Sun, Lina; Zhou, Boping; Liang, Mifang; Zhou, Paul; Wang, Xinquan; Zhang, Linqi

    2015-12-04

    Understanding the mechanism of protective antibody recognition against highly pathogenic avian influenza A virus H5N1 in humans is critical for the development of effective therapies and vaccines. Here we report the crystal structure of three H5-specific human monoclonal antibodies bound to the globular head of hemagglutinin (HA) with distinct epitope specificities, neutralization potencies and breadth. A structural and functional analysis of these epitopes combined with those reported elsewhere identifies four major vulnerable sites on the globular head of H5N1 HA. Chimeric and vulnerable site-specific mutant pseudoviruses are generated to delineate broad neutralization specificities of convalescent sera from two individuals who recovered from the infection with H5N1 virus. Our results show that the four vulnerable sites on the globular head rather than the stem region are the major neutralizing targets, suggesting that during natural H5N1 infection neutralizing antibodies against the globular head work in concert to provide protective antibody-mediated immunity.

  7. T-705 (favipiravir) activity against lethal H5N1 influenza A viruses.

    Science.gov (United States)

    Kiso, Maki; Takahashi, Kazumi; Sakai-Tagawa, Yuko; Shinya, Kyoko; Sakabe, Saori; Le, Quynh Mai; Ozawa, Makoto; Furuta, Yousuke; Kawaoka, Yoshihiro

    2010-01-12

    The neuraminidase inhibitors oseltamivir and zanamivi are used to treat H5N1 influenza. However, oseltamivir-resistant H5N1 viruses have been isolated from oseltamivir-treated patients. Moreover, reassortment between H5N1 viruses and oseltamvir-resistant human H1N1 viruses currently circulating could create oseltamivir-resistant H5N1 viruses, rendering the oseltamivir stockpile obsolete. Therefore, there is a need for unique and effective antivirals to combat H5N1 influenza viruses. The investigational drug T-705 (favipiravir; 6-fluoro-3-hydroxy-2-pyrazinecarboxamide) has antiviral activity against seasonal influenza viruses and a mouse-adapted H5N1 influenza virus derived from a benign duck virus. However, its efficacy against highly pathogenic H5N1 viruses, which are substantially more virulent, remains unclear. Here, we demonstrate that T-705 effectively protects mice from lethal infection with oseltamivir-sensitive or -resistant highly pathogenic H5N1 viruses. Furthermore, our biochemical analysis suggests that T-705 ribofuranosyl triphosphate, an active form of T-705, acts like purines or purine nucleosides in human cells and does not inhibit human DNA synthesis. We conclude that T-705 shows promise as a therapeutic agent for the treatment of highly pathogenic H5N1 influenza patients.

  8. Simultaneous detection and differentiation by multiplex real time RT-PCR of highly pathogenic avian influenza subtype H5N1 classic (clade 2.2.1 proper and escape mutant (clade 2.2.1 variant lineages in Egypt

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    Arafa Abdel-Satar

    2010-10-01

    Full Text Available Abstract Background The endemic status of highly pathogenic avian influenza virus (HPAIV of subtype H5N1 in Egypt continues to devastate the local poultry industry and poses a permanent threat for human health. Several genetically and antigenically distinct H5N1 lineages co-circulate in Egypt: Strains of clade 2.2.1 proper replicate mainly in backyard birds causing the bulk of human infections, while a variant lineage within 2.2.1 (2.2.1v appears to be perpetuated mainly in commercial poultry farms in Egypt. Viruses of the 2.2.1v lineage represent drift variants escaping from conventional vaccine-induced immunity and some of these strains also escaped detection by commercial real time reverse transcriptase PCR (RT-qPCR protocols due to mismatches in the primers/probe binding sites. Results We developed therefore a versatile, sensitive and lineage-specific multiplex RT-qPCR for detection and typing of H5N1 viruses in Egypt. Analytical characterization was carried out using 50 Egyptian HPAIV H5N1 strains isolated since 2006 and 45 other avian influenza viruses (AIV. A detection limit of 400 cRNA copies per ml sample matrix was found. Higher diagnostic sensitivity of the multiplex assay in comparison to other generic H5 or M-gene based RT-qPCR assays were found by examination of 63 swab samples from experimentally infected chickens and 50 AIV-positive swab samples from different host species in the field in Egypt. Conclusions The new multiplex RT-qPCR assay could be useful for rapid high-throughput monitoring for the presence of HPAIV H5N1 in commercial poultry in Egypt. It may also aid in prospective epidemiological studies to further delineate and better control spread of HPAIV H5N1 in Egypt.

  9. A model to control the epidemic of H5N1 influenza at the source

    Directory of Open Access Journals (Sweden)

    Li KS

    2007-11-01

    Full Text Available Abstract Background No country is fully prepared for a 1918-like pandemic influenza. Averting a pandemic of H5N1 influenza virus depends on the successful control of its endemicity, outbreaks in poultry and occasional spillage into human which carries a case-fatality rate of over 50%. The use of perimetric depopulation and vaccination has failed to halt the spread of the epidemic. Blanket vaccination for all poultry over a large geographical area is difficult. A combination of moratorium, segregation of water fowls from chickens and vaccination have been proved to be effective in the Hong Kong Special Administrative Region (HKSAR since 2002 despite endemicity and outbreaks in neighbouring regions. Systematic surveillance in southern China showed that ducks and geese are the primary reservoirs which transmit the virus to chickens, minor poultry and even migratory birds. Presentation of the hypothesis We hypothesize that this combination of moratorium, poultry segregation and targeted vaccination if successfully adapted to an affected district or province in any geographical region with high endemicity would set an example for the control in other regions. Testing the hypothesis A planned one-off moratorium of 3 weeks at the hottest month of the year should decrease the environmental burden as a source of re-infection. Backyard farms will then be re-populated by hatchlings from virus-free chickens and minor poultry only. Targeted immunization of the ducks and geese present only in the industrial farms and also the chickens would be strictly implemented as blanket immunization of all backyard poultry is almost impossible. Freely grazing ducks and geese would not be allowed until neutralizing antibodies of H5 subtype virus is achieved. As a proof of concept, a simple mathematical model with susceptible-infected-recovered (SIR structure of coupled epidemics between aquatic birds (mainly ducks and geese and chickens was used to estimate

  10. 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.

  11. 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.

  12. Different immunity elicited by recombinant H5N1 hemagglutinin proteins containing pauci-mannose, high-mannose, or complex type N-glycans.

    Directory of Open Access Journals (Sweden)

    Shih-Chang Lin

    Full Text Available Highly pathogenic avian influenza H5N1 viruses can result in poultry and occasionally in human mortality. A safe and effective H5N1 vaccine is urgently needed to reduce the pandemic potential. Hemagglutinin (HA, a major envelope protein accounting for approximately 80% of spikes in influenza virus, is often used as a major antigen for subunit vaccine development. In this study, we conducted a systematic study of the immune response against influenza virus infection following immunization with recombinant HA proteins expressed in insect (Sf9 cells, insect cells that contain exogenous genes for elaborating N-linked glycans (Mimic and mammalian cells (CHO. While the antibody titers are higher with the insect cell derived HA proteins, the neutralization and HA inhibition titers are much higher with the mammalian cell produced HA proteins. Recombinant HA proteins containing tri- or tetra-antennary complex, terminally sialylated and asialyated-galactose type N-glycans induced better protective immunity in mice to lethal challenge. The results are highly relevant to issues that should be considered in the production of fragment vaccines.

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

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    Robert G Wallace

    Full Text Available BACKGROUND: 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. METHODOLOGY AND PRINCIPAL FINDINGS: 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. CONCLUSIONS: The analysis demonstrates phylogenies can provide local health officials with more than hypotheses about relatedness. Pathogen dispersal, the

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

    Science.gov (United States)

    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

    2013-10-01

    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 Vietnam.

  15. An RNA conformational shift in recent H5N1 influenza A viruses

    NARCIS (Netherlands)

    Gultyaev, A.P.; Heus, H.A.; Olsthoorn, R.C.

    2007-01-01

    Recent outbreaks of avian influenza are being caused by unusually virulent H5N1 strains. It is unknown what makes these recent H5N1 strains more aggressive than previously circulating strains. Here, we have compared more than 3000 RNA sequences of segment 8 of type A influenza viruses and found a un

  16. Highlight the significance of genetic evolution of H5N1 avian flu

    Institute of Scientific and Technical Information of China (English)

    LU Jia-hai; ZHANG Ding-mei; WANG Guo-ling

    2006-01-01

    @@ Agrowing concern has focused on the recent identification of influenza A H5N1 virus in Asia.Previously thought to infect only wild birds and poultry, H5N1 has now infected humans, cats, pigs,and other mammals in an ongoing outbreak, often with fatal results. According to a report from the World Health Organization (WHO), 217 human H5N1 cases have been confirmed and 123 of them have been fatal as of May 19, 2006.1 But many questions remain unanswered, for example how the H5N1 virus could cross species barriers and acquire the ability to infect humans; when and how the H5N1 virus will transmit effectively between humans and cause an influenza pandemic; and what are the determinants of its high virulence. This article summarizes research progress on the origin of H5N1 virus, factors determining pathogenicity, the contribution of genetic evolution to H5N1 species barrier traversal, human-to-human transmission, and problems in prevention and treatment of H5N1 avian influenza virus.

  17. 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...

  18. Induction of protection against divergent H5N1 influenza viruses using a recombinant fusion protein linking influenza M2e to Onchocerca volvulus activation associated protein-1 (ASP-1) adjuvant.

    Science.gov (United States)

    Zhao, Guangyu; Du, Lanying; Xiao, Wenjun; Sun, Shihui; Lin, Yongping; Chen, Min; Kou, Zhihua; He, Yuxian; Lustigman, Sara; Jiang, Shibo; Zheng, Bo-Jian; Zhou, Yusen

    2010-10-18

    Our previous studies have shown the adjuvanticity of an Onchocerca volvulus recombinant protein, Ov-ASP-1 (ASP-1), when administered in an aqueous formulation with bystander vaccine antigens or commercial vaccines. In this study, we reported a novel formulation that took advantage of the protein nature of the ASP-1 adjuvant by creating recombinant fusion protein vaccines linking the highly conserved extracellular domain of M2 protein (M2e) consensus sequence of H5N1 influenza viruses with the ASP-1 adjuvant. Two recombinant fusion proteins designated M2e-ASP-1 and M2e3-ASP-1 were studied, in which ASP-1 was fused with one or three tandem copies of the M2e antigen. Our results show that these novel recombinant influenza vaccines, particularly M2e3-ASP-1, induced strong anti-M2e-specific humoral and cellular immune responses in the established mouse model. Furthermore, M2e3-ASP-1 was able to provide significant cross-clade protection against divergent H5N1 viruses. Consequently, this study has demonstrated a potential novel vaccine formulation that could provide a complementary prophylactic strategy in preventing the threat of future influenza outbreak resulting from rapid evolution of the H5N1 virus and co-circulation of multiple antigenic variants in various regions. Copyright © 2010 Elsevier Ltd. All rights reserved.

  19. Genetic characterization of 2008 reassortant influenza A virus (H5N1, Thailand

    Directory of Open Access Journals (Sweden)

    Wongphatcharachai Manoosak

    2010-09-01

    Full Text Available Abstract In January and November 2008, outbreaks of avian influenza have been reported in 4 provinces of Thailand. Eight Influenza A H5N1 viruses were recovered from these 2008 AI outbreaks and comprehensively characterized and analyzed for nucleotide identity, genetic relatedness, virulence determinants, and possible sites of reassortment. The results show that the 2008 H5N1 viruses displayed genetic drift characteristics (less than 3% genetic differences, as commonly found in influenza A viruses. Based on phylogenetic analysis, clade 1 viruses in Thailand were divided into 3 distinct branches (subclades 1, 1.1 and 1.2. Six out of 8 H5N1 isolates have been identified as reassorted H5N1 viruses, while other isolates belong to an original H5N1 clade. These viruses have undergone inter-lineage reassortment between subclades 1.1 and 1.2 and thus represent new reassorted 2008 H5N1 viruses. The reassorted viruses have acquired gene segments from H5N1, subclade 1.1 (PA, HA, NP and M and subclade 1.2 (PB2, PB1, NA and NS in Thailand. Bootscan analysis of concatenated whole genome sequences of the 2008 H5N1 viruses supported the reassortment sites between subclade 1.1 and 1.2 viruses. Based on estimating of the time of the most recent common ancestors of the 2008 H5N1 viruses, the potential point of genetic reassortment of the viruses could be traced back to 2006. Genetic analysis of the 2008 H5N1 viruses has shown that most virulence determinants in all 8 genes of the viruses have remained unchanged. In summary, two predominant H5N1 lineages were circulating in 2008. The original CUK2-like lineage mainly circulated in central Thailand and the reassorted lineage (subclades 1.1 and 1.2 predominantly circulated in lower-north Thailand. To prevent new reassortment, emphasis should be put on prevention of H5N1 viruses circulating in high risk areas. In addition, surveillance and whole genome sequencing of H5N1 viruses should be routinely performed for

  20. Evaluation of a conserved HA274-288 epitope to detect antibodies to highly pathogenic avian influenza virus H5N1 in Indonesian commercial poultry.

    Science.gov (United States)

    Wawegama, Nadeeka K; Tarigan, Simson; Indriani, Risa; Selleck, Paul; Adjid, Rm Abdul; Syafriati, Tati; Hardiman; Durr, Peter A; Ignjatovic, Jagoda

    2016-08-01

    A peptide enzyme linked immunosorbent assay (ELISA) based on an epitope in the haemagglutinin (HA) of avian influenza virus H5N1, amino acid positions 274-288 (HA274-288) was evaluated for detection of H5N1-specific antibodies. An optimized ELISA based on the tetrameric form of the HA274-288 epitope designated MP15 gave low background with non-immune chicken sera and detected vaccinated and infected birds. The HA274-288 epitope was highly conserved in Indonesian H5N1 strains and antibody responses were detected in the majority of the vaccinated chickens regardless of the H5N1 strain used for vaccination. The HA274-288 epitope was also conserved in the majority of H5N1 strains from the neighbouring Asian region, and other H5 subtypes potentially allowing for a wider use of the MP15 ELISA in H5N1 vaccinated and infected flocks. The MP15 ELISA results correlated significantly with haemagglutination inhibition (HI) test results and test sensitivity and specificity were 87% and 92%, respectively. The MP15 ELISA titres were significantly higher than the HI titres in all immune sera allowing for sera to be tested at a single dilution of 1:400 which is of advantage in routine surveillance. The study indicated that the MP15 ELISA is potentially useful for serological detection of H5N1 vaccinated or infected poultry and to have some advantages over the standard HI test for routine monitoring of flocks' immunity after vaccination.

  1. Lemna (duckweed) expressed hemagglutinin from avian influenza H5N1 protects chickens against H5N1 high pathogenicity avian influenza virus challenge

    Science.gov (United States)

    In the last two decades, transgenic plants have been explored as safe and cost effective alternative expression platforms for producing recombinant proteins. In this study, a synthetic hemagglutinin (HA) gene from the high pathogenicity avian influenza (HPAI) virus A/chicken/Indonesia/7/2003 (H5N1)...

  2. H5N1 病毒感染及其防治现状

    Institute of Scientific and Technical Information of China (English)

    孙丽萍; 马静

    2007-01-01

    @@ 高致病性禽流感病毒-H5N1(Avian Influenza A Virus-H5N1)不仅影响了家禽,而且已经跨越种属障碍,感染人类,并导致许多病例病死.H5N1 病毒感染的流行尚未得到有效控制,还在呈范围不断扩大、感染动物种类增加的态势.本文综合有关文献,对人 H5N1 病毒感染的一些特征、临床病例处置以及 H5N1 病毒研究进展[1],以及人 H5N1 病毒感染防治措施进行了梳理,旨在探讨加强人 H5N1 病毒感染的预防与控制.

  3. Endothelial cell tropism is a determinant of H5N1 pathogenesis in mammalian species.

    Directory of Open Access Journals (Sweden)

    Smanla Tundup

    2017-03-01

    Full Text Available The cellular and molecular mechanisms underpinning the unusually high virulence of highly pathogenic avian influenza H5N1 viruses in mammalian species remains unknown. Here, we investigated if the cell tropism of H5N1 virus is a determinant of enhanced virulence in mammalian species. We engineered H5N1 viruses with restricted cell tropism through the exploitation of cell type-specific microRNA expression by incorporating microRNA target sites into the viral genome. Restriction of H5N1 replication in endothelial cells via miR-126 ameliorated disease symptoms, prevented systemic viral spread and limited mortality, despite showing similar levels of peak viral replication in the lungs as compared to control virus-infected mice. Similarly, restriction of H5N1 replication in endothelial cells resulted in ameliorated disease symptoms and decreased viral spread in ferrets. Our studies demonstrate that H5N1 infection of endothelial cells results in excessive production of cytokines and reduces endothelial barrier integrity in the lungs, which culminates in vascular leakage and viral pneumonia. Importantly, our studies suggest a need for a combinational therapy that targets viral components, suppresses host immune responses, and improves endothelial barrier integrity for the treatment of highly pathogenic H5N1 virus infections.

  4. Spatio-temporal dynamics of global H5N1 outbreaks match bird migration patterns.

    Science.gov (United States)

    Si, Yali; Skidmore, Andrew K; Wang, Tiejun; de Boer, Willem F; Debba, Pravesh; Toxopeus, Albert G; Li, Lin; Prins, Herbert H T

    2009-11-01

    The global spread of highly pathogenic avian influenza H5N1 in poultry, wild birds and humans, poses a significant pandemic threat and a serious public health risk. An efficient surveillance and disease control system relies on the understanding of the dispersion patterns and spreading mechanisms of the virus. A space-time cluster analysis of H5N1 outbreaks was used to identify spatio-temporal patterns at a global scale and over an extended period of time. Potential mechanisms explaining the spread of the H5N1 virus, and the role of wild birds, were analyzed. Between December 2003 and December 2006, three global epidemic phases of H5N1 influenza were identified. These H5N1 outbreaks showed a clear seasonal pattern, with a high density of outbreaks in winter and early spring (i.e., October to March). In phase I and II only the East Asia Australian flyway was affected. During phase III, the H5N1 viruses started to appear in four other flyways: the Central Asian flyway, the Black Sea Mediterranean flyway, the East Atlantic flyway and the East Africa West Asian flyway. Six disease cluster patterns along these flyways were found to be associated with the seasonal migration of wild birds. The spread of the H5N1 virus, as demonstrated by the space-time clusters, was associated with the patterns of migration of wild birds. Wild birds may therefore play an important role in the spread of H5N1 over long distances. Disease clusters were also detected at sites where wild birds are known to overwinter and at times when migratory birds were present. This leads to the suggestion that wild birds may also be involved in spreading the H5N1 virus over short distances.

  5. Spatio-temporal dynamics of global H5N1 outbreaks match bird migration patterns

    Directory of Open Access Journals (Sweden)

    Yali Si

    2009-11-01

    Full Text Available The global spread of highly pathogenic avian influenza H5N1 in poultry, wild birds and humans, poses a significant pandemic threat and a serious public health risk. An efficient surveillance and disease control system relies on the understanding of the dispersion patterns and spreading mechanisms of the virus. A space-time cluster analysis of H5N1 outbreaks was used to identify spatio-temporal patterns at a global scale and over an extended period of time. Potential mechanisms explaining the spread of the H5N1 virus, and the role of wild birds, were analyzed. Between December 2003 and December 2006, three global epidemic phases of H5N1 influenza were identified. These H5N1 outbreaks showed a clear seasonal pattern, with a high density of outbreaks in winter and early spring (i.e., October to March. In phase I and II only the East Asia Australian flyway was affected. During phase III, the H5N1 viruses started to appear in four other flyways: the Central Asian flyway, the Black Sea Mediterranean flyway, the East Atlantic flyway and the East Africa West Asian flyway. Six disease cluster patterns along these flyways were found to be associated with the seasonal migration of wild birds. The spread of the H5N1 virus, as demonstrated by the space-time clusters, was associated with the patterns of migration of wild birds. Wild birds may therefore play an important role in the spread of H5N1 over long distances. Disease clusters were also detected at sites where wild birds are known to overwinter and at times when migratory birds were present. This leads to the suggestion that wild birds may also be involved in spreading the H5N1 virus over short distances.

  6. The changing nature of avian influenza A virus (H5N1).

    Science.gov (United States)

    Watanabe, Yohei; Ibrahim, Madiha S; Suzuki, Yasuo; Ikuta, Kazuyoshi

    2012-01-01

    Highly pathogenic avian influenza A virus subtype H5N1 has been endemic in some bird species since its emergence in 1996 and its ecology, genetics and antigenic properties have continued to evolve. This has allowed diverse virus strains to emerge in endemic areas with altered receptor specificity, including a new H5 sublineage with enhanced binding affinity to the human-type receptor. The pandemic potential of H5N1 viruses is alarming and may be increasing. We review here the complex dynamics and changing nature of the H5N1 virus that may contribute to the emergence of pandemic strains.

  7. An Overview of the Highly Pathogenic H5N1 Influenza Virus

    Institute of Scientific and Technical Information of China (English)

    Jingchuan Yin; Shi Liu; Ying Zhu

    2013-01-01

    Since the first human case of H5N1 avian influenza virus infection was reported in 1997,this highly pathogenic virus has infected hundreds of people around the world and resulted in many deaths.The ability of H5N1 to cross species boundaries,and the presence of polymorphisms that enhance virulence,present challenges to developing clear strategies to prevent the pandemic spread of this highly pathogenic avian influenza (HPAI) virus.This review summarizes the current understanding of,and recent research on,the avian influenza H5N1 virus,including transmission,virulence,pathogenesis,clinical characteristics,treatment and prevention.

  8. Biological fitness and natural selection of amantadine resistant variants of avian influenza H5N1 viruses.

    Science.gov (United States)

    Abdelwhab, E M; Veits, Jutta; Mettenleiter, Thomas C

    2017-01-15

    Outbreaks caused by the highly pathogenic H5N1 avian influenza virus (A/H5N1) devastated the poultry industry in several countries and posed a significant pandemic threat. In addition to culling of infected poultry and vaccination, amantadine has been applied in poultry in some countries to control the spread of the virus. The prevalence of the amantadine resistance marker at position 31 (Ser31Asn) of the M2 protein increased over time. However, little is known about the biological fitness and selection of H5N1 amantadine resistant strains over their sensitive counterparts. Here, using reverse genetics we investigated the biological impact of Ser31Asn in M2 commonly seen in viruses in clade 2.2.1.1 in farmed poultry in Egypt. Findings of the current study indicated that the resistance to amantadine conferred by Asn31 evolved rapidly after the application of amantadine in commercial poultry. Both the resistant and sensitive strains replicated at similar levels in avian cell culture. Asn31 increased virus entry into the cells and cell-to-cell spread and was genetically stable for several passages in cell culture. Moreover, upon co-infection of cell culture resistant strains dominated sensitive viruses even in the absence of selection by amantadine. Together, rapid emergence, stability and domination of amantadine-resistant variants over sensitive strains limit the efficacy of amantadine in poultry.

  9. Human avian influenza A (H5N1) virus infection in China

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Highly pathogenic influenza A (H5N1) virus causes a widespread poultry deaths worldwide. The first human H5N1 infected case was reported in Hong Kong Special Administrative Region of China in 1997. Since then, the virus re-emerged in 2003 and continues to infect people worldwide. Currently, over 400 human infections have been reported in more than 15 countries and mortality rate is greater than 60%. H5N1 viruses still pose a potential pandemic threat in the future because of the continuing global spread and evolution. Here, we summarize the epidemiological, clinical and virological characteristics of human H5N1 infection in China monitored and identified by our national surveillance systems.

  10. Hemagglutinin-based polyanhydride nanovaccines against H5N1 influenza elicit protective virus neutralizing titers and cell-mediated immunity

    Directory of Open Access Journals (Sweden)

    Ross KA

    2014-12-01

    Full Text Available Kathleen A Ross,1 Hyelee Loyd,2 Wuwei Wu,2 Lucas Huntimer,3 Shaheen Ahmed,4 Anthony Sambol,5 Scott Broderick,6 Zachary Flickinger,2 Krishna Rajan,6 Tatiana Bronich,4 Surya Mallapragada,1 Michael J Wannemuehler,3 Susan Carpenter,2 Balaji Narasimhan1 1Chemical and Biological Engineering, Iowa State University, Ames, IA, USA; 2Animal Science, Iowa State University, Ames, IA, USA; 3Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, USA; 4Pharmaceutical Sciences, University of Nebraska Medical Center, Omaha, NE, USA; 5Pathology and Microbiology, University of Nebraska Medical Center, Omaha, NE, USA; 6Materials Science and Engineering, Iowa State University, Ames, IA, USA Abstract: H5N1 avian influenza is a significant global concern with the potential to become the next pandemic threat. Recombinant subunit vaccines are an attractive alternative for pandemic vaccines compared to traditional vaccine technologies. In particular, polyanhydride nanoparticles encapsulating subunit proteins have been shown to enhance humoral and cell-mediated immunity and provide protection upon lethal challenge. In this work, a recombinant H5 hemagglutinin trimer (H53 was produced and encapsulated into polyanhydride nanoparticles. The studies performed indicated that the recombinant H53 antigen was a robust immunogen. Immunizing mice with H53 encapsulated into polyanhydride nanoparticles induced high neutralizing antibody titers and enhanced CD4+ T cell recall responses in mice. Finally, the H53-based polyanhydride nanovaccine induced protective immunity against a low-pathogenic H5N1 viral challenge. Informatics analyses indicated that mice receiving the nanovaccine formulations and subsequently challenged with virus were similar to naïve mice that were not challenged. The current studies provide a basis to further exploit the advantages of polyanhydride nanovaccines in pandemic scenarios. Keywords: polymer, nanoparticle, vaccine, subunit

  11. Domestic pigs have low susceptibility to H5N1 highly pathogenic avian influenza viruses.

    Directory of Open Access Journals (Sweden)

    Aleksandr S Lipatov

    2008-07-01

    Full Text Available Genetic reassortment of H5N1 highly pathogenic avian influenza viruses (HPAI with currently circulating human influenza A strains is one possibility that could lead to efficient human-to-human transmissibility. Domestic pigs which are susceptible to infection with both human and avian influenza A viruses are one of the natural hosts where such reassortment events could occur. Virological, histological and serological features of H5N1 virus infection in pigs were characterized in this study. Two- to three-week-old domestic piglets were intranasally inoculated with 10(6 EID(50 of A/Vietnam/1203/04 (VN/04, A/chicken/Indonesia/7/03 (Ck/Indo/03, A/Whooper swan/Mongolia/244/05 (WS/Mong/05, and A/Muscovy duck/Vietnam/ 209/05 (MDk/VN/05 viruses. Swine H3N2 and H1N1 viruses were studied as a positive control for swine influenza virus infection. The pathogenicity of the H5N1 HPAI viruses was also characterized in mouse and ferret animal models. Intranasal inoculation of pigs with H5N1 viruses or consumption of infected chicken meat did not result in severe disease. Mild weight loss was seen in pigs inoculated with WS/Mong/05, Ck/Indo/03 H5N1 and H1N1 swine influenza viruses. WS/Mong/05, Ck/Indo/03 and VN/04 viruses were detected in nasal swabs of inoculated pigs mainly on days 1 and 3. Titers of H5N1 viruses in nasal swabs were remarkably lower compared with those of swine influenza viruses. Replication of all four H5N1 viruses in pigs was restricted to the respiratory tract, mainly to the lungs. Titers of H5N1 viruses in the lungs were lower than those of swine viruses. WS/Mong/05 virus was isolated from trachea and tonsils, and MDk/VN/05 virus was isolated from nasal turbinate of infected pigs. Histological examination revealed mild to moderate bronchiolitis and multifocal alveolitis in the lungs of pigs infected with H5N1 viruses, while infection with swine influenza viruses resulted in severe tracheobronchitis and bronchointerstitial pneumonia. Pigs

  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. Host gene expression profiling in influenza A virus-infected lung epithelial (A549 cells: a comparative analysis between highly pathogenic and modified H5N1 viruses

    Directory of Open Access Journals (Sweden)

    Chakrabarti Alok K

    2010-09-01

    Full Text Available Abstract Background To understand the molecular mechanism of host responses to highly pathogenic avian influenza virus infection and to get an insight into the means through which virus overcomes host defense mechanism, we studied global gene expression response of human lung carcinoma cells (A549 at early and late stages of infection with highly pathogenic avian Influenza A (H5N1 virus and compared it with a reverse genetics modified recombinant A (H5N1 vaccine virus using microarray platform. Results The response was studied at time points 4, 8, 16 and 24 hours post infection (hpi. Gene ontology analysis revealed that the genes affected by both the viruses were qualitatively similar but quantitatively different. Significant differences were observed in the expression of genes involved in apoptosis and immune responses, specifically at 16 hpi. Conclusion We conclude that subtle differences in the ability to induce specific host responses like apoptotic mechanism and immune responses make the highly pathogenic viruses more virulent.

  14. Systems-level comparison of host-responses elicited by avian H5N1 and seasonal H1N1 influenza viruses in primary human macrophages.

    Science.gov (United States)

    Lee, Suki M Y; Gardy, Jennifer L; Cheung, C Y; Cheung, Timothy K W; Hui, Kenrie P Y; Ip, Nancy Y; Guan, Y; Hancock, Robert E W; Peiris, J S Malik

    2009-12-14

    Human disease caused by highly pathogenic avian influenza (HPAI) H5N1 can lead to a rapidly progressive viral pneumonia leading to acute respiratory distress syndrome. There is increasing evidence from clinical, animal models and in vitro data, which suggests a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. The key target cells for the virus in the lung are the alveolar epithelium and alveolar macrophages, and we have shown that, compared to seasonal human influenza viruses, equivalent infecting doses of H5N1 viruses markedly up-regulate pro-inflammatory cytokines in both primary cell types in vitro. Whether this H5N1-induced dysregulation of host responses is driven by qualitative (i.e activation of unique host pathways in response to H5N1) or quantitative differences between seasonal influenza viruses is unclear. Here we used microarrays to analyze and compare the gene expression profiles in primary human macrophages at 1, 3, and 6 h after infection with H5N1 virus or low-pathogenic seasonal influenza A (H1N1) virus. We found that host responses to both viruses are qualitatively similar with the activation of nearly identical biological processes and pathways. However, in comparison to seasonal H1N1 virus, H5N1 infection elicits a quantitatively stronger host inflammatory response including type I interferon (IFN) and tumor necrosis factor (TNF)-alpha genes. A network-based analysis suggests that the synergy between IFN-beta and TNF-alpha results in an enhanced and sustained IFN and pro-inflammatory cytokine response at the early stage of viral infection that may contribute to the viral pathogenesis and this is of relevance to the design of novel therapeutic strategies for H5N1 induced respiratory disease.

  15. Systems-level comparison of host-responses elicited by avian H5N1 and seasonal H1N1 influenza viruses in primary human macrophages.

    Directory of Open Access Journals (Sweden)

    Suki M Y Lee

    Full Text Available Human disease caused by highly pathogenic avian influenza (HPAI H5N1 can lead to a rapidly progressive viral pneumonia leading to acute respiratory distress syndrome. There is increasing evidence from clinical, animal models and in vitro data, which suggests a role for virus-induced cytokine dysregulation in contributing to the pathogenesis of human H5N1 disease. The key target cells for the virus in the lung are the alveolar epithelium and alveolar macrophages, and we have shown that, compared to seasonal human influenza viruses, equivalent infecting doses of H5N1 viruses markedly up-regulate pro-inflammatory cytokines in both primary cell types in vitro. Whether this H5N1-induced dysregulation of host responses is driven by qualitative (i.e activation of unique host pathways in response to H5N1 or quantitative differences between seasonal influenza viruses is unclear. Here we used microarrays to analyze and compare the gene expression profiles in primary human macrophages at 1, 3, and 6 h after infection with H5N1 virus or low-pathogenic seasonal influenza A (H1N1 virus. We found that host responses to both viruses are qualitatively similar with the activation of nearly identical biological processes and pathways. However, in comparison to seasonal H1N1 virus, H5N1 infection elicits a quantitatively stronger host inflammatory response including type I interferon (IFN and tumor necrosis factor (TNF-alpha genes. A network-based analysis suggests that the synergy between IFN-beta and TNF-alpha results in an enhanced and sustained IFN and pro-inflammatory cytokine response at the early stage of viral infection that may contribute to the viral pathogenesis and this is of relevance to the design of novel therapeutic strategies for H5N1 induced respiratory disease.

  16. The Mx1 gene protects mice against the pandemic 1918 and highly lethal human H5N1 influenza viruses.

    Science.gov (United States)

    Tumpey, Terrence M; Szretter, Kristy J; Van Hoeven, Neal; Katz, Jacqueline M; Kochs, Georg; Haller, Otto; García-Sastre, Adolfo; Staeheli, Peter

    2007-10-01

    Mice carrying a wild-type Mx1 gene (Mx1+/+) differ from standard laboratory mice (Mx1-/-) in being highly resistant to infection with common laboratory strains of influenza A virus. We report that Mx1 also protects mice against the pandemic human 1918 influenza virus and a highly lethal human H5N1 strain from Vietnam. Resistance to H5N1 of Mx1+/+ but not Mx1-/- mice was enhanced if the animals were treated with a single dose of exogenous alpha interferon before infection. Thus, the interferon-induced resistance factor Mx1 represents a key component of the murine innate immune system that mediates protection against epidemic and pandemic influenza viruses.

  17. Generation and Characterization of Monoclonal Antibodies Specific to Avian Influenza H5N1 Hemagglutinin Protein.

    Science.gov (United States)

    Malik, Ankita; Mallajosyula, V Vamsee Aditya; Mishra, Nripendra Nath; Varadarajan, Raghavan; Gupta, Satish Kumar

    2015-12-01

    Highly pathogenic avian influenza (HPAI) H5N1 virus has in the past breached the species barrier from infected domestic poultry to humans in close contact. Although human-to-human transmission has previously not been reported, HPAI H5N1 virus has pandemic potential owing to gain of function mutation(s) and/or genetic reassortment with human influenza A viruses. Monoclonal antibodies (MAbs) have been used for diagnosis as well as specific therapeutic candidates in several disease conditions including viral infections in humans. In this study, we describe the preliminary characterization of four murine MAbs developed against recombinant hemagglutinin (rHA) protein of avian H5N1 A/turkey/Turkey/1/2005 virus that are either highly specific or broadly reactive against HA from other H5N1 subtype viruses, such as A/Hong Kong/213/03, A/Common magpie/Hong Kong/2256/2006, and A/Barheaded goose/Quinghai/14/2008. The antibody binding is specific to H5N1 HAs, as none of the antibodies bound H1N1, H2N2, H3N2, or B/Brisbane/60/2008 HAs. Out of the four MAbs, one of them (MA-7) also reacted weakly with the rHA protein of H7N9 A/Anhui/1/2013. All four MAbs bound H5 HA (A/turkey/Turkey/1/2005) with high affinity with an equilibrium dissociation constant (KD) ranging between 0.05 and 10.30 nM. One of the MAbs (MA-1) also showed hemagglutination inhibition activity (HI titer; 31.25 μg/mL) against the homologous A/turkey/Turkey/1/2005 H5N1 virus. These antibodies may be useful in developing diagnostic tools for detection of influenza H5N1 virus infection.

  18. Is avian influenza virus A(H5N1) a real threat to human health?

    Science.gov (United States)

    Amendola, A; Ranghiero, A; Zanetti, A; Pariani, E

    2011-09-01

    The A(H5N1) influenza remains a disease of birds with a significant species barrier: in the presence of some tens million cases of infection in poultry--with a wide geographical spread--, only a few hundreds cases have occurred in humans. To date, human cases have been reported in 15 countries--mainly in Asia--and all were related to the onset of outbreaks in poultry. A peak of H5N1 human cases was recorded in 2006, then decreasing in subsequent years. Despite this trend, the H5N1 virus still represents a possible threat to human health, considering that more than half of human cases of H5N1 have been fatal. Moreover, despite the drop in the number of cases, the risk of a novel pandemic cannot be excluded, since H5N1 continues to circulate in poultry in countries with elevated human population density and where monitoring systems are not fully appropriate. In addition, there is a major global concern about the potential occurrence of a reassortment between the 2009 pandemic H1N1 and the highly pathogenic H5N1 influenza viruses following a co-infection in a susceptible host. Therefore, the implementation of appropriate surveillance and containment measures is crucial in order to minimize such risk. In conclusion, H5N1 avian influenza is still a rare disease in humans but its clinical severe outcome requires a careful monitoring of the virus's ability to evolve and to trigger a new pandemic.

  19. Waterfowl potential as resevoirs of high pathogenic avian influenza H5N1 viruses

    Directory of Open Access Journals (Sweden)

    R Susanti

    2007-06-01

    Full Text Available The high population of waterfowl subsequently with the high case fatality of poultry and people in West Java regency caused by HPAI H5N1 can raise possibility that waterfowl was a natural reservoir. This research aimed to prove that waterfowl in West Java served as reservoir of AI virus (primarily H5N1 and also identify the virus pathotype based on cleavage site of amino acid sequence. Cloacal swab sample was obtained from healthy and unvaccinated waterfowl from Sukabumi and Bogor Regency. Cloacal swab was propagated in 9 days old embryonic chicken eggs. Allantoic fluid was harvested at the 4th day of incubation and then tested for hemagglutination, and positive isolate continued with virus sub-typing using PCR method. H5 gene from H5N1 isolate then sequenced using dideoxy termination method. Multiple alignment of nucleotide sequences were analysed using MEGA-3.1 program. Sub-typing using PCR method indicated the existence of 25 strain H5N1, 16 strain HxN1, 4 strain H5Nx and 9 virus ND. Characterization of cleavage site amino acid sequence indicated that all H5N1 sample were pathogenic with sequence QRERRRKKR (23 sample dan QRESRRKKR (2 sample. Waterfowl was HPAI H5N1 virus reservoir. Asymptomatic infection in waterfowl, but the virus shedding gradually occurred and therefore it became potential source of H5N1 virus infection. Our findings suggest that immediate action is needed to prevent the transmission of highly pathogenic avian influenza viruses from the apparently healthy waterfowl into terrestrial poultry or human.

  20. Neurovirulence of H5N1 infection in ferrets is mediated by multifocal replication in distinct permissive neuronal cell regions.

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    Jennifer R Plourde

    Full Text Available Highly pathogenic avian influenza A (HPAI, subtype H5N1, remains an emergent threat to the human population. While respiratory disease is a hallmark of influenza infection, H5N1 has a high incidence of neurological sequelae in many animal species and sporadically in humans. We elucidate the temporal/spatial infection of H5N1 in the brain of ferrets following a low dose, intranasal infection of two HPAI strains of varying neurovirulence and lethality. A/Vietnam/1203/2004 (VN1203 induced mortality in 100% of infected ferrets while A/Hong Kong/483/1997 (HK483 induced lethality in only 20% of ferrets, with death occurring significantly later following infection. Neurological signs were prominent in VN1203 infection, but not HK483, with seizures observed three days post challenge and torticollis or paresis at later time points. VN1203 and HK483 replication kinetics were similar in primary differentiated ferret nasal turbinate cells, and similar viral titers were measured in the nasal turbinates of infected ferrets. Pulmonary viral titers were not different between strains and pathological findings in the lungs were similar in severity. VN1203 replicated to high titers in the olfactory bulb, cerebral cortex, and brain stem; whereas HK483 was not recovered in these tissues. VN1203 was identified adjacent to and within the olfactory nerve tract, and multifocal infection was observed throughout the frontal cortex and cerebrum. VN1203 was also detected throughout the cerebellum, specifically in Purkinje cells and regions that coordinate voluntary movements. These findings suggest the increased lethality of VN1203 in ferrets is due to increased replication in brain regions important in higher order function and explains the neurological signs observed during H5N1 neurovirulence.

  1. Highly pathogenic H5N1 influenza A virus strains provoke heterogeneous IFN-α/β responses that distinctively affect viral propagation in human cells.

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    Markus Matthaei

    Full Text Available The fatal transmissions of highly pathogenic avian influenza A viruses (IAV of the H5N1 subtype to humans and high titer replication in the respiratory tract indicate that these pathogens can overcome the bird-to-human species barrier. While type I interferons (IFN-α/β are well described to contribute to the species barrier of many zoonotic viruses, current data to the role of these antiviral cytokines during human H5N1 IAV infections is limited and contradictory. We hypothesized an important role for the IFN system in limiting productive infection of avian H5N1 strains in human cells. Hence, we examined IFN-α/β gene activation by different avian and human H5N1 isolates, if the IFN-α/β response restricts H5N1 growth and whether the different strains were equally capable to regulate the IFN-α/β system via their IFN-antagonistic NS1 proteins. Two human H5N1 isolates and a seasonal H3N2 strain propagated efficiently in human respiratory cells and induced little IFN-β, whereas three purely avian H5N1 strains were attenuated for replication and provoked higher IFN secretion. Replication of avian viruses was significantly enhanced on interferon-deficient cells, and exogenous IFN potently limited the growth of all strains in human cells. Moreover, IFN-α/β activation by all strains depended on retinoic acid-inducible gene I excluding principal differences in receptor activation between the different viruses. Interestingly, all H5N1 NS1 proteins suppressed IFN-α/β induction comparably well to the NS1 of seasonal IAV. Thus, our study shows that H5N1 strains are heterogeneous in their capacity to activate human cells in an NS1-independent manner. Our findings also suggest that H5N1 viruses need to acquire adaptive changes to circumvent strong IFN-α/β activation in human host cells. Since no single amino acid polymorphism could be associated with a respective high- or low induction phenotype we propose that the necessary adaptations to

  2. Global distribution patterns of highly pathogenic H5N1 avian influenza: environmental vs. socioeconomic factors.

    Science.gov (United States)

    Chen, Youhua; Chen, You-Fang

    2014-01-01

    In this report, we quantitatively analyzed the essential ecological factors that were strongly correlated with the global outbreak of highly pathogenic H5N1 avian influenza. The ecological niche modeling (ENM) was used to reveal the potential outbreak hotspots of H5N1. A two-step modeling procedure has been proposed: we first used BioClim model to obtain the coarse suitable areas of H5N1, and then those suitable areas with very high probabilities were retained as the inputs of multiple-variable autologistic regression analysis (MAR) for model refinement. MAR was implemented taking spatial autocorrelation into account. The final performance of ENM was evaluated using the areas under the curve (AUC) of receiver-operating characteristic. In addition, principal component analysis (PCA) was employed to reveal the most important variables and relevant ecological gradients of H5N1 outbreak. Niche visualization was used to identify potential spreading trend of H5N1 along important ecological gradients. For the first time, we combined socioeconomic and environmental variables as joint predictors in developing ecological niche modeling. Environmental variables represented the natural element related to H5N1 outbreak, whereas socioeconomic ones represented the anthropogenic element. Our results indicated that: (1) the high-risk hotspots are mainly located in temperate zones (indicated by ENM)-correspondingly, we argued that the "ecoregions hypothesis" was reasonable to some extent; (2) evaporation, humidity, human population density, livestock population density were the first four important factors (in descending order) that were associated with the H5N1 global outbreak (indicated by PCA); (3) influenza had a tendency to expand into areas with low evaporation (indicated by niche visualization). In conclusion, our study substantiates that both the environmental and socioeconomic variables jointly determined the global spreading trend of H5N1, but environmental variables

  3. A SPR aptasensor for detection of avian influenza virus H5N1.

    Science.gov (United States)

    Bai, Hua; Wang, Ronghui; Hargis, Billy; Lu, Huaguang; Li, Yanbin

    2012-01-01

    Rapid and specific detection of avian influenza virus (AIV) is urgently needed due to the concerns over the potential outbreaks of highly pathogenic H5N1 influenza in animals and humans. Aptamers are artificial oligonucleic acids that can bind specific target molecules, and show comparable affinity for target viruses and better thermal stability than monoclonal antibodies. The objective of this research was to use a DNA-aptamer as the specific recognition element in a portable Surface Plasmon Resonance (SPR) biosensor for rapid detection of AIV H5N1 in poultry swab samples. A SPR biosensor was fabricated using selected aptamers that were biotinylated and then immobilized on the sensor gold surface coated with streptavidin via streptavidin-biotin binding. The immobilized aptamers captured AIV H5N1 in a sample solution, which caused an increase in the refraction index (RI). After optimizing the streptavidin and aptamer parameters, the results showed that the RI value was linearly related (R(2) = 0.99) to the concentration of AIV in the range of 0.128 to 1.28 HAU. Negligible signal (H5N1) was observed from six non-target AIV subtypes. The AIV H5N1 in poultry swab samples with concentrations of 0.128 to 12.8 HAU could be detected using this aptasensor in 1.5 h.

  4. A SPR Aptasensor for Detection of Avian Influenza Virus H5N1

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    Huaguang Lu

    2012-09-01

    Full Text Available Rapid and specific detection of avian influenza virus (AIV is urgently needed due to the concerns over the potential outbreaks of highly pathogenic H5N1 influenza in animals and humans. Aptamers are artificial oligonucleic acids that can bind specific target molecules, and show comparable affinity for target viruses and better thermal stability than monoclonal antibodies. The objective of this research was to use a DNA-aptamer as the specific recognition element in a portable Surface Plasmon Resonance (SPR biosensor for rapid detection of AIV H5N1 in poultry swab samples. A SPR biosensor was fabricated using selected aptamers that were biotinylated and then immobilized on the sensor gold surface coated with streptavidin via streptavidin-biotin binding. The immobilized aptamers captured AIV H5N1 in a sample solution, which caused an increase in the refraction index (RI. After optimizing the streptavidin and aptamer parameters, the results showed that the RI value was linearly related (R2 = 0.99 to the concentration of AIV in the range of 0.128 to 1.28 HAU. Negligible signal ( < 4% of H5N1 was observed from six non-target AIV subtypes. The AIV H5N1 in poultry swab samples with concentrations of 0.128 to 12.8 HAU could be detected using this aptasensor in 1.5 h.

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

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    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.

  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. Greater virulence of highly pathogenic H5N1 influenza virus in cats than in dogs.

    Science.gov (United States)

    Kim, Heui Man; Park, Eun Hye; Yum, Jung; Kim, Hyun Soo; Seo, Sang Heui

    2015-01-01

    Highly pathogenic H5N1 influenza virus continues to infect animals and humans. We compared the infectivity and pathogenesis of H5N1 virus in domestic cats and dogs to find out which animal is more susceptible to H5N1 influenza virus. When cats and dogs were infected with the H5N1 virus, cats suffered from severe outcomes including death, whereas dogs did not show any mortality. Viruses were shed in the nose and rectum of cats and in the nose of dogs. Viruses were detected in brain, lung, kidney, intestine, liver, and serum in the infected cats, but only in the lung in the infected dogs. Genes encoding inflammatory cytokines and chemokines, Toll-like receptors, and apoptotic factors were more highly expressed in the lungs of cats than in those of dogs. Our results suggest that the intensive monitoring of dogs is necessary to prevent human infection by H5N1 influenza virus, since infected dogs may not show clear clinical signs, in contrast to infected cats.

  8. Pathogenicity of Highly Pathogenic Avian Influenza Virus H5N1 in Naturally Infected Poultry in Egypt.

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    Ibrahim Thabet Hagag

    Full Text Available Highly pathogenic avian influenza virus (HPAIV H5N1 has been endemic in Egypt since 2006, and there is increasing concern for its potential to become highly transmissible among humans. Infection by HPAIV H5N1 has been described in experimentally challenged birds. However, the pathogenicity of the H5N1 isolated in Egypt has never been reported in naturally infected chickens and ducks. Here we report a 2013 outbreak of HPAIV H5N1 in commercial poultry farms and backyards in Sharkia Province, Egypt. The main symptoms were ecchymosis on the shanks and feet, cyanosis of the comb and wattles, subcutaneous edema of the head and neck for chickens, and nervous signs (torticollis for ducks. Within 48-72 hrs of the onset of illness, the average mortality rates were 22.8-30% and 28.5-40% in vaccinated chickens and non-vaccinated ducks, respectively. Tissue samples of chickens and ducks were collected for analyses with cross-section immunohistochemistry and real-time RT-PCR for specific viral RNA transcripts. While viral RNA was detected in nearly all tissues and sera collected, viral nucleoprotein was detected almost ubiquitously in all tissues, including testis. Interestingly, viral antigen was also observed in endothelial cells of most organs in chickens, and clearly detected in the trachea and brain in particular. Viral nucleoprotein was also detected in mononuclear cells of various organs, especially pulmonary tissue. We performed phylogenetic analyses and compared the genomic sequences of the hemagglutinin (HA and nonstructural proteins (NS among the isolated viruses, the HPAIV circulated in Egypt in the past and currently, and some available vaccine strains. Further analysis of deduced amino acids of both HA and NS1 revealed that our isolates carried molecular determinants of HPAIV, including the multibasic amino acids (PQGERRRK/KR*GLF in the cleavage site in HA and glutamate at position 92 (D92E in NS1. This is the first report of the pathogenicity

  9. Characterisation of enzymatic activities of H5N1 influenza virus

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    Simson Tarigan

    2008-06-01

    Full Text Available One of the two glycoproteins projected from the surface of the influenza virus is identified as neuraminidase. This enzyme enables the virus to spread in the host, and therefore it plays vital roles in the viral pathogenicity. From the viewpoint of disease control, neuraminidase is used as the target for the development of anti-flu drugs, and for the development of diagnostic test to differentiate infected from vaccinated animals (DIVA. Since the roles of the enzyme are very important, information regarding the characteristics and the procedure to measure its activity, which is the purpose of this study, is essential. The optimum incubation time of the neuraminidase-substrate (fetuin reaction and the optimum pH of the buffer were determined. The stability of the enzyme against heating, supplementation or chelating of calcium ion, and b-propiolactone treatment were analysed. This study showed that neuraminidase from H5N1-influenza virus was, in regards to the characteristics investigated in this study, was comparable to that from Clostridium perfringens. The optimum incubation time for the viral and Clostridial neuraminidases were 60 and 30 minutes, respectively; whereas, the optimum pH for both neuraminidase was 6-7. At pH 8, both neuraminidase were inactive. Supplementation of calcium ion tended to increase activity but chelating of the cation did not have any observable effects. Treatment with 0.2% b-propiolactone for 6 hours reduced the activity, whereas heating at 60°C for 60 minutes abolished all activity. Since inactivation by b-propiolactone is partially only, neuraminidase assay could be performed safely in ordinary laboratories using b-propiolactone-treated-influenza virus, rather than the life virus. The thermolabile nature of the enzyme will complicate any attempt to purify the enzyme.

  10. The activation of B cells enhances DC-SIGN expression and promotes susceptibility of B cells to HPAI H5N1 infection.

    Science.gov (United States)

    Na-Ek, Prasit; Thewsoongnoen, Jutarat; Thanunchai, Maytawan; Wiboon-Ut, Suwimon; Sa-Ard-Iam, Noppadol; Mahanonda, Rangsini; Thitithanyanont, Arunee

    2017-09-02

    The interplay between highly pathogenic avian influenza (HPAI) H5N1 virus and immune cells has been extensively studied for years, as host immune components are thought to play significant roles in promoting the systemic spread of the virus and responsible for cytokine storm. Previous studies suggested that the interaction of B cells and monocytes could promote HPAI H5N1 infection by enhancing avian influenza virus receptor expression. In this study, we further investigate the relationship between the HPAI H5N1 virus, activated B cells, and DC-SIGN expression. DC-SIGN has been described as an important factor for mediating various types of viral infection. Here, we first demonstrate that HPAI H5N1 infection could induce an activation of B cells, which was associated with DC-SIGN expression. Using CD40L and recombinant IL-4 for B cell stimulation, we determined that DC-SIGN expressed on activated B cells was able to enhance its susceptibility to HPAI H5N1 infection. Our findings uncover the interplay between this H5N1 virus and B cells and provide important information in understanding how the virus overcomes our immune system, contributing to its unusual immunopathogenesis. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Mx1 gene protects mice against the highly lethal human H5N1 influenza virus.

    Science.gov (United States)

    Salomon, Rachelle; Staeheli, Peter; Kochs, Georg; Yen, Hui-Ling; Franks, John; Rehg, Jerold E; Webster, Robert G; Hoffmann, Erich

    2007-10-01

    We investigated the importance of the host Mx1 gene in protection against highly pathogenic H5N1 avian influenza virus. Mice expressing the Mx1 gene survived infection with the lethal human H5N1 isolate A/Vietnam/1203/04 and with reassortants combining its genes with those of the non-lethal virus A/chicken/Vietnam/C58/04, while all Mx1-/- mice succumbed. Mx1-expressing mice showed lower organ virus titers, fewer lesions, and less pulmonary inflammation. Our data support the hypothesis that Mx1 expression protects mice against the high pathogenicity of H5N1 virus through inhibition of viral polymerase activity ultimately resulting in reduced viral growth and spread. Drugs that mimic this mechanism may be protective in humans.

  12. 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.

  13. Characterization of low-pathogenicity H5N1 avian influenza viruses from North America

    Science.gov (United States)

    Spackman, Erica; Swayne, David E.; Suarez, David L.; Senne, Dennis A.; Pedersen, Janice C.; Killian, Mary Lea; Pasick, John; Handel, Katherine; Somanathan Pillai, Smitha; Lee, Chang-Won; Stallknecht, David; Slemons, Richard; Ip, Hon S.; Deliberto, Tom

    2007-01-01

    Wild-bird surveillance in North America for avian influenza (AI) viruses with a goal of early identification of the Asian H5N1 highly pathogenic AI virus has identified at least six low-pathogenicity H5N1 AI viruses between 2004 and 2006. The hemagglutinin (HA) and neuraminidase (NA) genes from all 6 H5N1 viruses and an additional 38 North American wild-bird-origin H5 subtype and 28 N1 subtype viruses were sequenced and compared with sequences available in GenBank by phylogenetic analysis. Both HA and NA were phylogenetically distinct from those for viruses from outside of North America and from those for viruses recovered from mammals. Four of the H5N1 AI viruses were characterized as low pathogenicity by standard in vivo pathotyping tests. One of the H5N1 viruses, A/MuteSwan/MI/451072-2/06, was shown to replicate to low titers in chickens, turkeys, and ducks. However, transmission of A/MuteSwan/MI/451072-2/06 was more efficient among ducks than among chickens or turkeys based on virus shed. The 50% chicken infectious dose for A/MuteSwan/MI/451072-2/06 and three other wild-waterfowl-origin H5 viruses were also determined and were between 105.3 and 107.5 50% egg infective doses. Finally, seven H5 viruses representing different phylogenetic clades were evaluated for their antigenic relatedness by hemagglutination inhibition assay, showing that the antigenic relatedness was largely associated with geographic origin. Overall, the data support the conclusion that North American H5 wild-bird-origin AI viruses are low-pathogenicity wild-bird-adapted viruses and are antigenically and genetically distinct from the highly pathogenic Asian H5N1 virus lineage.

  14. Characterization of low-pathogenicity H5N1 avian influenza viruses from North America

    Science.gov (United States)

    Spackman, Erica; Swayne, D. E.; Suarez, D. L.; Senne, D. A.; Pedersen, J. C.; Killian, M. L.; Pasick, J.; Handel, K.; Pillai, S. P. S.; Lee, C. -W.; Stallknecht, D.; Slemons, R.; Ip, H. S.; Deliberto, T.

    2007-01-01

    Wild-bird surveillance in North America for avian influenza (AI) viruses with a goal of early identification of the Asian H5N1 highly pathogenic AI virus has identified at least six low-pathogenicity H5N1 AI viruses between 2004 and 2006. The hemagglutinin (HA) and neuraminidase (NA) genes from all 6 H5N1 viruses and an additional 38 North American wild-bird-origin H5 subtype and 28 N1 subtype viruses were sequenced and compared with sequences available in GenBank by phylogenetic analysis. Both HA and NA were phylogenetically distinct from those for viruses from outside of North America and from those for viruses recovered from mammals. Four of the H5N1 AI viruses were characterized as low pathogenicity by standard in vivo pathotyping tests. One of the H5N1 viruses, A/MuteSwan/MI/451072-2/06, was shown to replicate to low titers in chickens, turkeys, and ducks. However, transmission of A/MuteSwan/MI/451072-2/06 was more efficient among ducks than among chickens or turkeys based on virus shed. The 50% chicken infectious dose for A/MuteSwan/MI/451072-2/06 and three other wild-waterfowl-origin H5 viruses were also determined and were between 10 5.3 and 107.5 50% egg infective doses. Finally, seven H5 viruses representing different phylogenetic clades were evaluated for their antigenic relatedness by hemagglutination inhibition assay, showing that the antigenic relatedness was largely associated with geographic origin. Overall, the data support the conclusion that North American H5 wild-bird-origin AI viruses are low-pathogenicity wild-bird-adapted viruses and are antigenically and genetically distinct from the highly pathogenic Asian H5N1 virus lineage. Copyright ?? 2007, American Society for Microbiology. All Rights Reserved.

  15. Retrospective space-time analysis of H5N1 Avian Influenza emergence in Thailand

    OpenAIRE

    Shanmugasundaram Jothiganesh; Gonzalez Jean-Paul; Souris Marc; Corvest Victoria; Kittayapong Pattamaporn

    2010-01-01

    Abstract Background The highly pathogenic avian influenza (HPAI) H5N1 virus remains a worldwide threat to human and animal health, while the mechanisms explaining its epizootic emergence and re-emergence in poultry are largely unknown. Data from Thailand, a country that experienced significant epidemics in poultry and has recorded suspicious cases of HPAI on a daily basis since 2004, are used here to study the process of emergence. A spatial approach is employed to describe all HPAI H5N1 viru...

  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. Gene expression responses to highly pathogenic avian influenza H5N1 virus infections in ducks

    Science.gov (United States)

    Differences in host response to infection with avian influenza (AI) viruses were investigated by identifying genes differentially expressed in tissues of infected ducks. Clear differences in pathogenicity were observed among ducks inoculated with five H5N1 HPAI viruses. Virus titers in tissues cor...

  18. The avian and mammalian host range of highly pathogenic avian H5N1 influenza.

    Science.gov (United States)

    Kaplan, Bryan S; Webby, Richard J

    2013-12-05

    Highly pathogenic H5N1 influenza viruses have been isolated from a number of avian and mammalian species. Despite intensive control measures the number of human and animal cases continues to increase. A more complete understanding of susceptible species and of contributing environmental and molecular factors is crucial if we are to slow the rate of new cases. H5N1 is currently endemic in domestic poultry in only a handful of countries with sporadic and unpredictable spread to other countries. Close contact of terrestrial bird or mammalian species with infected poultry/waterfowl or their biological products is the major route for interspecies transmission. Intra-species transmission of H5N1 in mammals, including humans, has taken place on a limited scale though it remains to be seen if this will change; recent laboratory studies suggest that it is indeed possible. Here we review the avian and mammalian species that are naturally susceptible to H5N1 infection and the molecular factors associated with its expanded host range.

  19. Pathogenesis of avian influenza A (H5N1) viruses in pigs

    Science.gov (United States)

    Background. Genetic reassortment of avian influenza H5N1 viruses with currently circulating human influenza A strains is one possibility that could lead to efficient human-to-human transmissibility. Domestic pigs which are susceptible to infection with both human and avian influenza A viruses are o...

  20. The pause on avian H5N1 influenza virus transmission research should be ended

    NARCIS (Netherlands)

    R.A.M. Fouchier (Ron); A. García-Sastre (Adolfo); Y. Kawaoka (Yoshihiro)

    2012-01-01

    textabstractA voluntary 60-day pause on avian H5N1 influenza virus transmission research was announced in January 2012 by the international community of influenza scientists engaged in this work to provide time to explain the benefits of such work and the risk mitigation measures in place. Subsequen

  1. Genetic insight of the H5N1 hemagglutinin cleavage site

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The cleavability of the hemagglutinin (HA) plays a major role in virulence of avian influenza viruses. Detailed analyses of the cleavage sequences and their evolution would give insights into the high pathogenicity of the H5N1 virus. HA segments were visually identifiable in the cellular automata (CA) image, and a feature gene segment (FGS) was only found in H5N1 rather than any other subtype. This FGS is a 30-bp gene segment mainly consisting of 'A' and 'G'. When translated into amino acids the FGS converted into a sequence of mainly basic amino acids with positive charges. This feature amino acid segment (FAAS) was located in the cleavage site loop of HA which was potentially cleavable by various proteases. The 3D structure of H5N1 HA was reconstructed using homology modelling. It was found that the cleavage site loop was well exposed to potential proteases. The molecular surfaces were reconstructed to study how mutation and deletion of some amino acids in the FAAS affected the charge distribution. It was found that some mutations had severely changed the landscape of the charge distribution. Statistical analyses of FAAS were made with respect to when and where the H5N1 viruses were found. In 2005, there were less un-mutated FAAS than the other years according to temporal evolution, and more mutated FAAS appeared in China than other regions according to geographic distribution. These results are helpful for exploring the evolution of virus high pathogenicity.

  2. 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 d

  3. A review on human influenza A H5N1 infections in Hong Kong

    Institute of Scientific and Technical Information of China (English)

    CHAN Paul K S

    2009-01-01

    Avian influenza A H5N1 remains the most threatening virus that may cause another devastating pan-demic in the foreseeable future, In 1997, Hong Kong was the first place to detect human infections due to this virus originated from birds. The experience and lessons learnt provide important information for controlling further outbreaks caused by avian influenza viruses.

  4. A review on human influenza A H5N1 infections in Hong Kong

    Institute of Scientific and Technical Information of China (English)

    CHAN; Paul; K; S

    2009-01-01

    Avian influenza A H5N1 remains the most threatening virus that may cause another devastating pandemic in the foreseeable future. In 1997, Hong Kong was the first place to detect human infections due to this virus originated from birds. The experience and lessons learnt provide important information for controlling further outbreaks caused by avian influenza viruses.

  5. Bird migration and risk for H5N1 transmission into Qinghai Lake, China.

    Science.gov (United States)

    Cui, Peng; Hou, Yuansheng; Xing, Zhi; He, Yubang; Li, Tianxian; Guo, Shan; Luo, Ze; Yan, Baoping; Yin, Zuohua; Lei, Fumin

    2011-05-01

    The highly pathogenic avian influenza H5N1 virus still cause devastating effects to humans, agricultural poultry flocks, and wild birds. Wild birds are also detected to carry H5N1 over long distances and are able to introduce it into new areas during migration. In this article, our objective is to provide lists of bird species potentially involved in the introduction of highly pathogenic avian influenza H5N1 in Qinghai Lake, which is an important breeding and stopover site for aquatic birds along the Central Asian Flyway. Bird species were classified according to the following behavioral and ecological factors: migratory status, abundance, degree of mixing species and gregariousness, and the prevalence rate of H5N1 virus. Most of the high-risk species were from the family Anatidae, order Anseriformes (9/14 in spring, 11/15 in fall). We also estimated the relative risk of bird species involved by using a semi-quantitative method; species from family Anatidae accounted for over 39% and over 91% of the total risk at spring and fall migration periods, respectively. Results also show the relative risk for each bird aggregating site in helping to identify high-risk areas. This work may also be instructive and meaningful to the avian influenza surveillance in the breeding, stopover, and wintering sites besides Qinghai Lake along the Central Asian Flyway.

  6. Molecular characteristic and pathogenicity of Indonesian H5N1 clade 2.3.2 viruses

    Directory of Open Access Journals (Sweden)

    Dharmayanti NLPI

    2013-06-01

    Full Text Available The outbreak of disease in late 2012 in Indonesia caused high duck mortality. The agent of the disease was identified as H5N1 clade 2.3.2. The disease caused economic loss to the Indonesian duck farmer. The clade 2.3.2 of H5N1 virus has not previously been identified, so this study was conducted to characterize 4 of H5N1 clade 2.3.2 viruses by DNA sequencing in eight genes segment virus namely HA, NA, NS, M, PB1, PB2, PA and NP. The pathogenicity test of clade 2.3.2 viruses in ducks was compared to clade 2.1.3 viruses which predominat circulating in Indonesia. Results of phylogenetic tree analysis showed that the four of clade 2.3.2 viruses isolated in 2012 was the new introduced virus from abroad. Further analysis showed eight genes were in one group with the clade 2.3.2 viruses, especially those from VietNam and did not belong to Indonesia viruses group. The pathogenicity test in ducks showed that virus H5N1 clade 2.3.2 and clade 2.1.3 have similar clinical symptoms and pathogenicity and cause death in 75% of ducks on days 3-6 after infection.

  7. Ecological determinants of highly pathogenic avian influenza (H5N1) outbreaks in Bangladesh

    DEFF Research Database (Denmark)

    Ahmed, Syed Sayeem Uddin; Ersbøll, Annette Kjær; Biswas, Paritosh K.

    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 diff...

  8. 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.

  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; W. Cao (W.)

    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. Evolution and adaptation of hemagglutinin gene of human H5N1 influenza virus.

    Science.gov (United States)

    Wei, Kaifa; Chen, Yanfeng; Chen, Juan; Wu, Lingjuan; Xie, Daoxin

    2012-06-01

    The H5N1 HPAI virus has brought heavy loss to poultry industry. Although, there exists limited human-to-human transmission, it poses potential serious risks to public health. HA is responsible for receptor-binding and membrane-fusion and contains the host receptor-binding sites and major epitopes for neutralizing antibodies. To investigate molecular adaption of HPAI H5N1 viruses, we performed a phylogenetic analysis of HA sequences with 240 HPAI virus strains isolated from human. The topology of the tree reveals overall clustering of strains in four major clusters based on geographic location, and shows antigenic diversity of HA of human H5N1 isolates co-circulating in Asia, Africa, and Europe. The four clusters possess distinct features within the cleavage site and glycosylation sites, respectively. We identified six sites apparently evolving under positive selection, five of which persist in the population. Three positively selected sites are found to be located either within or flanking the receptor-binding sites, suggesting that selection at these sites may increase the affinity to human-type receptor. Furthermore, some sites are also associated with glycosylation and antigenic changes. In addition, two sites are found to be selected differentially in the two clusters. The analyses provide us deep insight into the adaptive evolution of human H5N1 viruses, show us several candidate mutations that could cause a pandemic, and suggest that efficiency measures should be taken to deal with potential risks.

  11. Knowledge discovery from mining the association between H5N1 outbreaks and environmental factors

    NARCIS (Netherlands)

    Si, Y.; Wang, T.; Skidmore, A.K.; Prins, H.H.T.

    2010-01-01

    The global spread of highly pathogenic avian influenza H5N1 in poultry, wild birds and humans, poses a significant panzootic threat and a serious public health risk. An efficient surveillance and disease control system requires a deep understanding of their spread mechanisms, including environmental

  12. 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

  13. Environmental factors contributing to the spread of H5N1 avian influenza in mainland China

    NARCIS (Netherlands)

    L.Q. Fang; S.J. de Vlas (Sake); S. Liang (Song); C.W.N. Looman (Caspar); P. Gong (Peng); B. Xu (Bing); L. Yan (Lei); H. Yang (Honghui); J.H. Richardus (Jan Hendrik); W.C. Cao (Wu Chun)

    2008-01-01

    textabstractBackground: Since late 2003, highly pathogenic avian influenza (HPAI) outbreaks caused by infection with H5N1 virus has led to the deaths of millions of poultry and more than 10 thousands of wild birds, and as of 18-March 2008, at least 373 laboratory-confirmed human infections with 236

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

    African Journals Online (AJOL)

    Rapid detection of the avian influenza virus H5N1 subtype in Egypt. ... Effective diagnosis and control management are needed to control the disease. ... rabbit serum, which secrete immunoglobulin G (IgG) was served as the detector antibody ...

  15. Spatial and temporal patterns of global H5N1 outbreaks

    CSIR Research Space (South Africa)

    Si, YL

    2008-07-01

    Full Text Available The global spread of highly pathogenic avian influenza (H5N1) in wild birds and poultry is considered a significant pandemic threat. Furthermore, human infections resulting from direct contact with infected birds/ poultry pose a serious public...

  16. H5N1 surveillance in migratory birds in Java, Indonesia.

    Science.gov (United States)

    Stoops, Arthur C; Barbara, Katie A; Indrawan, Mochamad; Ibrahim, Ima N; Petrus, Wicaksana B; Wijaya, Susan; Farzeli, Arik; Antonjaya, Ungke; Sin, Lim W; Hidayatullah, N; Kristanto, Ige; Tampubolon, A M; Purnama, S; Supriatna, Adam; Burgess, Timothy H; Williams, Maya; Putnam, Shannon D; Tobias, Steve; Blair, Patrick J

    2009-12-01

    We sought to elucidate the role of migratory birds in transmission of H5N1 in an enzoonotic area. Resident, captive, and migratory birds were sampled at five sites in Java, Indonesia. Mist nets were used to trap birds. Birds were identified to species. RNA was extracted from swabs and reverse transcriptase polymerase chain reaction (RT-PCR) conducted for the HA and M genes of H5N1. Antibodies were detected by enzyme-linked immunosorbent assay and hemagglutination inhibition test. Between October 2006 and September 2007, a total of 4,067 captive, resident, and migratory birds comprising 98 species in 23 genera were sampled. The most commonly collected birds were the common sandpiper (6% of total), striated heron (3%), and the domestic chicken (14%). The overall prevalence of H5N1 antibodies was 5.3%. A significantly higher percentage of captive birds (16.1%) showed antibody evidence of H5N1 exposure when compared to migratory or resident birds. The greatest number of seropositive birds in each category were Muschovy duck (captive), striated heron (resident), and the Pacific golden plover (migratory). Seven apparently well captive birds yielded molecular evidence of H5N1 infection. Following amplification, the HA, NA, and M genes were analyzed. Phylogenetic analysis of the HA gene showed that the isolates were 97% similar to EU124153.1 A/chicken/West Java/Garut May 2006, an isolate obtained in a similar region of West Java. While no known markers of neuraminidase inhibitor resistance were found within the NA gene, M segment analysis revealed the V27A mutation known to confer resistance to adamantanes. Our results demonstrate moderate serologic evidence of H5N1 infection in captive birds, sampled in five sites in Java, Indonesia, but only occasional infection in resident and migratory birds. These data imply that in an enzoonotic region of Indonesia the role of migratory birds in transmission of H5N1 is limited.

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Intersubtype Reassortments of H5N1 Highly Pathogenic Avian Influenza Viruses Isolated from Quail.

    Science.gov (United States)

    Nguyen, Tinh Huu; Than, Van Thai; Thanh, Hien Dang; Hung, Vu-Khac; Nguyen, Duc Tan; Kim, Wonyong

    2016-01-01

    H5N1 highly pathogenic avian influenza (HPAI) viruses are considered a threat to national animal industries, causing production losses and high mortality in domestic poultry. In recent years, quail has become a popular terrestrial poultry species raised for production of meat and eggs in Asia. In this study, to better understand the roles of quail in H5N1 viral evolution, two H5N1-positive samples, designated A/quail/Vietnam/CVVI-49/2010 (CVVI-49/2010) and A/quail/Vietnam/CVVI-50/2014 (CVVI-50/2014), were isolated from quail during H5N1 outbreaks in Vietnam, and their whole genome were analyzed. The phylogenetic analysis reveals new evolutionary variation in the worldwide H5N1 viruses. The quail HA genes were clustered into clades 1.1.1 (CVVI-49/2010) and clade 2.3.2.1c (CVVI-50/2014), which may have evolved from viruses circulating from chickens and/or ducks in Cambodia, mainland of China, Taiwan, Indonesia, and South Korea in recent years. Interestingly, the M2 gene of the CVVI-49/2010 strain contained amino acid substitutions at position 26L-I and 31S-N that are related to amantadine-resistance. In particular, the CVVI-50/2014 strain revealed evidence of multiple intersubtype reassortment events between virus clades 2.3.2.1c, 2.3.2.1b, and 2.3.2.1a. Data from this study supports the possible role of quail as an important intermediate host in avian influenza virus evolution. Therefore, additional surveillance is needed to monitor these HPAI viruses both serologically and virologically in quail.

  19. Detection of antibody responses by using haemagglutination inhibiton test and the protection titer of avian influenza virus H5N1 subtype

    Directory of Open Access Journals (Sweden)

    Risa Indriani

    2004-10-01

    Full Text Available Study on the detection of antibody responses using haemagglutination inhibition (HI test and the protection titer to Avian influenza (AI virus H5N1 subtype local isolate has been conducted at the Research Institute for Veterinary Science (RIVS. A total number of 50 village chicken (10 chicken served as un-injected controls and 30 quail were injected intramuscularly with inactivated virus of AI H5N1 subtype local isolate. Serum samples were collected 3 weeks after injection and were tested using haemagglutination inhibition tests. The correlation between antibody titer and its protection to AI virus H5N1 local isolate were measured by challenging the birds with AI virus H5N1 local isolate The HI test was then used to determine field serum samples. A total number of 48 village chicken from three (3 Districts (Bekasi, Tangerang and Bogor and 96 quails from two (2 farms in District of Sukabumi which were all vaccinated with commercial AI adjuvant vaccine were sampled. The study revealed that village chicken and quails showed antibody responses after 3 weeks vaccination and that titer of ≥ 3 log 2 was able to protect chicken and quails when they were challenged with local isolate virus. Based on this result, village chicken field samples from Districts of Tangerang, Bekasi and Bogor showed antibody titer which will protect 50, 100 and 85% of the flocks respectively. While quail field samples from Farm I and Farm II in District of Sukabumi showed antibody titer which will protect 60-100% and 0-80% of the flocks respectively. It is concluded that the study has successfully measured antibody titer to AI virus H5N1 subtype which protect village chicken and quails from local isolate virus challenge so that the results will be used to analyze field serum samples after vaccination program to eradicate AI from Indonesia.

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

    OpenAIRE

    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

    2016-01-01

    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 demonstr...

  1. 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

  2. Interspecies transmission and host restriction of avian H5N1 influenza virus

    Institute of Scientific and Technical Information of China (English)

    LIU Di; LIU XiaoLing; YAN JingHua; LIU Wen-Jun; GAO George Fu

    2009-01-01

    Long-term endemicity of avian H5N1 influenza virus in poultry and continuous sporadic human infec-tions in several countries has raised the concern of another potential pandemic influenza. Suspicion of the avian origin of the previous pandemics results in the close investigation of the mechanism of in-terspecies transmission. Entry and fusion is the first step for the H5N1 influenza virus to get into the host cells affecting the host ranges. Therefore receptor usage study has been a major focus for the last few years. We now know the difference of the sialic acid structures and distributions in different spe-cies, even in the different parts of the same host. Many host factors interacting with the influenza virus component proteins have been identified and their role in the host range expansion and interspecies transmission is under detailed scrutiny. Here we review current progress in the receptor usage and host factors.

  3. Interspecies transmission and host restriction of avian H5N1 influenza virus

    Institute of Scientific and Technical Information of China (English)

    GAO; George; Fu

    2009-01-01

    Long-term endemicity of avian H5N1 influenza virus in poultry and continuous sporadic human infections in several countries has raised the concern of another potential pandemic influenza. Suspicion of the avian origin of the previous pandemics results in the close investigation of the mechanism of interspecies transmission. Entry and fusion is the first step for the H5N1 influenza virus to get into the host cells affecting the host ranges. Therefore receptor usage study has been a major focus for the last few years. We now know the difference of the sialic acid structures and distributions in different species, even in the different parts of the same host. Many host factors interacting with the influenza virus component proteins have been identified and their role in the host range expansion and interspecies transmission is under detailed scrutiny. Here we review current progress in the receptor usage and host factors.

  4. Avian Influenza (H5N1) Expert System using Dempster-Shafer Theory

    CERN Document Server

    Maseleno, Andino

    2012-01-01

    Based on Cumulative Number of Confirmed Human Cases of Avian Influenza (H5N1) Reported to World Health Organization (WHO) in the 2011 from 15 countries, Indonesia has the largest number death because Avian Influenza which 146 deaths. In this research, the researcher built an Avian Influenza (H5N1) Expert System for identifying avian influenza disease and displaying the result of identification process. In this paper, we describe five symptoms as major symptoms which include depression, combs, wattle, bluish face region, swollen face region, narrowness of eyes, and balance disorders. We use chicken as research object. Research location is in the Lampung Province, South Sumatera. The researcher reason to choose Lampung Province in South Sumatera on the basis that has a high poultry population. Dempster-Shafer theory to quantify the degree of belief as inference engine in expert system, our approach uses Dempster-Shafer theory to combine beliefs under conditions of uncertainty and ignorance, and allows quantitat...

  5. Metapopulation dynamics enable persistence of influenza A, including A/H5N1, in poultry.

    Science.gov (United States)

    Hosseini, Parviez Rana; Fuller, Trevon; Harrigan, Ryan; Zhao, Delong; Arriola, Carmen Sofia; Gonzalez, Armandoe; Miller, Matthew Joshua; Xiao, Xiangming; Smith, Tom B; Jones, Jamie Holland; Daszak, Peter

    2013-01-01

    Highly pathogenic influenza A/H5N1 has persistently but sporadically caused human illness and death since 1997. Yet it is still unclear how this pathogen is able to persist globally. While wild birds seem to be a genetic reservoir for influenza A, they do not seem to be the main source of human illness. Here, we highlight the role that domestic poultry may play in maintaining A/H5N1 globally, using theoretical models of spatial population structure in poultry populations. We find that a metapopulation of moderately sized poultry flocks can sustain the pathogen in a finite poultry population for over two years. Our results suggest that it is possible that moderately intensive backyard farms could sustain the pathogen indefinitely in real systems. This fits a pattern that has been observed from many empirical systems. Rather than just employing standard culling procedures to control the disease, our model suggests ways that poultry production systems may be modified.

  6. Molecular epidemiology of influenza A (H5N1) viruses, Bangladesh, 2007-2011.

    Science.gov (United States)

    Hoque, Md Ahasanul; Tun, Hein Min; Hassan, Mohammad Mahmudul; Khan, Shahneaz Ali; Islam, Skm Azizul; Islam, Md Nurul; Giasuddin, Md; Osmani, Tabm Muzaffar Goni; Islam, Ariful; Thornton, Ronald Norman; Burgess, Graham William; Skerratt, Lee Francis; Selleck, Paul; Brun, Edgar; Debnath, Nitish Chandra; Leung, Frederick Chi-Ching

    2013-09-01

    To investigate the origins, evolution and patterns of spread of HPAI H5N1 outbreaks in Bangladesh, we performed a phylogenetic reconstruction analysis using Bayesian methods. The analysis was conducted using 81 hemagglutinin (HA) gene sequences from the H5N1 viruses isolated in Bangladesh from 2007 to 2011, together with 264 publicly available HA sequences of clade 2.2, 2.3.2 and 2.3.4 retrieved from GenBank. Our study provides evidence that clade 2.2.2 viruses that caused outbreaks in Bangladesh were lineages independent from the viruses introduced earlier into India. Furthermore, the Bangladesh clade 2.2.2 descendents subsequently spread to India and Bhutan. This has implications for avian influenza control in southern Asia suggesting multiple routes of entry of the virus including one pathway that spread to neighboring countries via Bangladesh.

  7. The variable codons of H5N1 avian influenza A virus haemagglutinin genes

    Institute of Scientific and Technical Information of China (English)

    Mark; J.GIBBS; Robert; W.MURPHY

    2008-01-01

    We investigated the selection pressures on the haemagglutinin genes of H5N1 avian influenza viruses using fixed effects likelihood models. We found evidence of positive selection in the sequences from isolates from 1997 to 2007, except viruses from 2000. The haemagglutinin sequences of viruses from southeast Asia, Hong Kong and mainland China were the most polymorphic and had similar nonsyn-onymous profiles. Some sites were positively selected in viruses from most regions and a few of these sites displayed different amino acid patterns. Selection appeared to produce different outcomes in vi-ruses from Europe, Africa and Russia and from different host types. One position was found to be positively selected for human isolates only. Although the functions of some positively selected posi-tions are unknown, our analysis provided evidence of different temporal, spatial and host adaptations for H5N1 avian influenza viruses.

  8. Cellular transcripts regulated during infections with Highly Pathogenic H5N1 Avian Influenza virus in 3 host systems

    Directory of Open Access Journals (Sweden)

    Noor Suriani M

    2011-04-01

    Full Text Available Abstract Background Highly pathogenic Avian Influenza (HPAI virus is able to infect many hosts and the virus replicates in high levels in the respiratory tract inducing severe lung lesions. The pathogenesis of the disease is actually the outcome of the infection as determined by complex host-virus interactions involving the functional kinetics of large numbers of participating genes. Understanding the genes and proteins involved in host cellular responses are therefore, critical for the elucidation of the mechanisms of infection. Methods Differentially expressed transcripts regulated in a H5N1 infections of whole lung organ of chicken, in-vitro chick embryo lung primary cell culture (CeLu and a continuous Madin Darby Canine Kidney cell line was undertaken. An improved mRNA differential display technique (Gene Fishing™ using annealing control primers that generates reproducible, authentic and long PCR products that are detectable on agarose gels was used for the identification of differentially expressed genes (DEGs. Seven of the genes have been selected for validation using a TaqMan® based real time quantitative PCR assay. Results Thirty seven known and unique differentially expressed genes from lungs of chickens, CeLu and MDCK cells were isolated. Among the genes isolated and identified include heat shock proteins, Cyclin D2, Prenyl (decaprenyl diphosphate synthase, IL-8 and many other unknown genes. The quantitative real time RT-PCR assay data showed that the transcription kinetics of the selected genes were clearly altered during infection by the Highly Pathogenic Avian Influenza virus. Conclusion The Gene Fishing™ technique has allowed for the first time, the isolation and identification of sequences of host cellular genes regulated during H5N1 virus infection. In this limited study, the differentially expressed genes in the three host systems were not identical, thus suggesting that their responses to the H5N1 infection may not share

  9. Analysis of the crow lung transcriptome in response to infection with highly pathogenic H5N1 avian influenza virus.

    Science.gov (United States)

    Vijayakumar, Periyasamy; Mishra, Anamika; Ranaware, Pradip B; Kolte, Atul P; Kulkarni, Diwakar D; Burt, David W; Raut, Ashwin Ashok

    2015-03-15

    The highly pathogenic avian influenza (HPAI) H5N1 virus, currently circulating in Asia, causes severe disease in domestic poultry as well as wild birds like crow. However, the molecular pathogenesis of HPAIV infection in crows and other wild birds is not well known. Thus, as a step to explore it, a comprehensive global gene expression analysis was performed on crow lungs, infected with HPAI H5N1 crow isolate (A/Crow/India/11TI11/2011) using high throughput next generation sequencing (NGS) (GS FLX Titanium XLR70). The reference genome of crow is not available, so RNA seq analysis was performed on the basis of a de novo assembled transcriptome. The RNA seq result shows, 4052 genes were expressed uniquely in noninfected, 6277 genes were expressed uniquely in HPAIV infected sample and of the 6814 genes expressed in both samples, 2279 genes were significantly differentially expressed. Our transcriptome profile data allows for the ability to understand the molecular mechanism behind the recent lethal HPAIV outbreak in crows which was, until recently, thought to cause lethal infections only in gallinaceous birds such as chickens, but not in wild birds. The pattern of differentially expressed genes suggest that this isolate of H5N1 virus evades the host innate immune response by attenuating interferon (IFN)-inducible signalling possibly by down regulating the signalling from type I IFN (IFNAR1 and IFNAR2) and type II IFN receptors, upregulation of the signalling inhibitors suppressor of cytokine signalling 1 (SOCS1) and SOCS3 and altering the expression of toll-like receptors (TLRs). This may be the reason for disease and mortality in crows. Copyright © 2015. Published by Elsevier B.V.

  10. Biosafety Considerations of Mammalian-Transmissible H5N1 Influenza

    OpenAIRE

    2012-01-01

    Abstract The ability to produce an H5N1 influenza virus that can be transmitted from human to human raises both biosecurity and biosafety concerns. After analyzing the biosafety risks of such a virus, we propose that it be handled at biosafety level 4 (BSL4) containment until and unless it becomes clear that the risks to humans and other mammals can be mitigated.

  11. Modelling H5N1 in Bangladesh across spatial scales: Model complexity and zoonotic transmission risk.

    Science.gov (United States)

    Hill, Edward M; House, Thomas; Dhingra, Madhur S; Kalpravidh, Wantanee; Morzaria, Subhash; Osmani, Muzaffar G; Yamage, Mat; Xiao, Xiangming; Gilbert, Marius; Tildesley, Michael J

    2017-09-01

    Highly pathogenic avian influenza H5N1 remains a persistent public health threat, capable of causing infection in humans with a high mortality rate while simultaneously negatively impacting the livestock industry. A central question is to determine regions that are likely sources of newly emerging influenza strains with pandemic causing potential. A suitable candidate is Bangladesh, being one of the most densely populated countries in the world and having an intensifying farming system. It is therefore vital to establish the key factors, specific to Bangladesh, that enable both continued transmission within poultry and spillover across the human-animal interface. We apply a modelling framework to H5N1 epidemics in the Dhaka region of Bangladesh, occurring from 2007 onwards, that resulted in large outbreaks in the poultry sector and a limited number of confirmed human cases. This model consisted of separate poultry transmission and zoonotic transmission components. Utilising poultry farm spatial and population information a set of competing nested models of varying complexity were fitted to the observed case data, with parameter inference carried out using Bayesian methodology and goodness-of-fit verified by stochastic simulations. For the poultry transmission component, successfully identifying a model of minimal complexity, which enabled the accurate prediction of the size and spatial distribution of cases in H5N1 outbreaks, was found to be dependent on the administration level being analysed. A consistent outcome of non-optimal reporting of infected premises materialised in each poultry epidemic of interest, though across the outbreaks analysed there were substantial differences in the estimated transmission parameters. The zoonotic transmission component found the main contributor to spillover transmission of H5N1 in Bangladesh was found to differ from one poultry epidemic to another. We conclude by discussing possible explanations for these discrepancies in

  12. Modelling H5N1 in Bangladesh across spatial scales: Model complexity and zoonotic transmission risk

    Directory of Open Access Journals (Sweden)

    Edward M. Hill

    2017-09-01

    Full Text Available Highly pathogenic avian influenza H5N1 remains a persistent public health threat, capable of causing infection in humans with a high mortality rate while simultaneously negatively impacting the livestock industry. A central question is to determine regions that are likely sources of newly emerging influenza strains with pandemic causing potential. A suitable candidate is Bangladesh, being one of the most densely populated countries in the world and having an intensifying farming system. It is therefore vital to establish the key factors, specific to Bangladesh, that enable both continued transmission within poultry and spillover across the human–animal interface. We apply a modelling framework to H5N1 epidemics in the Dhaka region of Bangladesh, occurring from 2007 onwards, that resulted in large outbreaks in the poultry sector and a limited number of confirmed human cases. This model consisted of separate poultry transmission and zoonotic transmission components. Utilising poultry farm spatial and population information a set of competing nested models of varying complexity were fitted to the observed case data, with parameter inference carried out using Bayesian methodology and goodness-of-fit verified by stochastic simulations. For the poultry transmission component, successfully identifying a model of minimal complexity, which enabled the accurate prediction of the size and spatial distribution of cases in H5N1 outbreaks, was found to be dependent on the administration level being analysed. A consistent outcome of non-optimal reporting of infected premises materialised in each poultry epidemic of interest, though across the outbreaks analysed there were substantial differences in the estimated transmission parameters. The zoonotic transmission component found the main contributor to spillover transmission of H5N1 in Bangladesh was found to differ from one poultry epidemic to another. We conclude by discussing possible explanations for

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

    Directory of Open Access Journals (Sweden)

    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.

  14. Serosurveillance study on transmission of H5N1 virus during a 2006 avian influenza epidemic.

    Science.gov (United States)

    Ceyhan, M; Yildirim, I; Ferraris, O; Bouscambert-Duchamp, M; Frobert, E; Uyar, N; Tezer, H; Oner, A F; Buzgan, T; Torunoglu, M A; Ozkan, B; Yilmaz, R; Kurtoglu, M G; Laleli, Y; Badur, S; Lina, B

    2010-09-01

    In 2006 an outbreak of avian influenza A(H5N1) in Turkey caused 12 human infections, including four deaths. We conducted a serological survey to determine the extent of subclinical infection caused by the outbreak. Single serum samples were collected from five individuals with avian influenza whose nasopharyngeal swabs tested positive for H5 RNA by polymerase chain reaction, 28 family contacts of the cases, 95 poultry cullers, 75 individuals known to have had contact with diseased chickens and 81 individuals living in the region with no known contact with infected chickens and/or patients. Paired serum samples were collected from 97 healthcare workers. All sera were tested for the presence of neutralizing antibodies by enzyme-linked immunoassay, haemagglutination inhibition and microneutralization assays. Only one serum sample, from a parent of an avian influenza patient, tested positive for H5N1 by microneutralization assay. This survey shows that there was minimal subclinical H5N1 infection among contacts of human cases and infected poultry in Turkey in 2006. Further, the low rate of subclinical infection following contact with diseased poultry gave further support to the reported low infectivity of the virus.

  15. 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

  16. 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

  17. 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.

  18. Prediction of a common neutralizing epitope of H5N1 avian influenza virus by in silico molecular docking

    Institute of Scientific and Technical Information of China (English)

    YAN YuanQing; XIA NingShao; LI ShaoWei; YANG ChunYan; LUO WenXin; WANG MingQiao; CHEN YiXin; LUO HaiFeng; WU Ting; ZHANG Jun

    2008-01-01

    The H5N1 avian influenza virus (AIV) has widely spread in Asia, Europe and Africa, making a large amount of economic loss. Recently, our research group has screened a common neutralizing mono-clonal antibody named 8H5, which can neutralize almost all H5 subtype AIV ever isolated so far. Obvi-ously, this monoclonal antibody would benefit for research and development of the universal AIV vac-cine and design of the drug against H5N1 AIV in high mutation rate. In this study, the homology mod-eling was applied to generate the 3D structure of 8H5 Fab fragment, and "canonical structure" method was used to define the specified loop conformation of CDR regions. The model was subjected to en-ergy minimization in cvff force field with Discovery module in Insight Ⅱ program. The resulting model has correct stereochemistry as gauged from the Ramachandran plot calculation and good 3D-structure compatibility as assessed by interaction energy analysis, solvent accessible surface (SAS) analysis, and Profiles-3D approach. Furthermore, the 8H5 Fab model was subjected to docking with three H5 subtype hemagglutinin (HA) structures deposited in PDB (ID No: 1jsm, 2ibx and 2fk0) respectively. The result indicates that the three docked complexes share a common binding interface, but differ in bind-ing angle related with HA structure similarity between viral subtypes. In the light of the three HA inter-faces with structural homology analysis, the common neutralizing epitope on HA recognized by 8H5 consists of 9 incontinuous amino acid residues: Asp68, Asn72, Glu112, Lys113, Ile114, Pro118, Ser120, Tyr137, Tyr252 (numbered as for 1jsm sequence), The primary purpose of the present work is to provide some insight into structure and binding details of a common neutralizing epitope of H5N1 AIV, thereby aiding in the structure-based design of universal AIV vaccines and anti-virus therapeutic drugs.

  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.

  20. The primary research on mouse and cat infected with A/Tiger/Harbin/01/2003(H5N1)

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    It was confirmed by WHOthat the H5N1viruses resultedinsevere or fatal respiratory disease inthe majority of infectedpersons,indicatingthat the H5N1viruses had crossedthe species barrier without genetic reassortment with a humanin-fluenza virus.To design more effective strategies for prevention and treatment of H5N1viruses infected,in the presentstudy,we used atiger original HPAIVA/Tiger/Harbin/01/2003(H5N1)propagated by SPFembryonated hen eggs to es-tablishinfected animal model.TCID50of virus was10-8/0·1ml ...

  1. Evidence for subclinical H5N1 avian influenza infections among Nigerian poultry workers.

    Science.gov (United States)

    Okoye, John O; Eze, Didacus C; Krueger, Whitney S; Heil, Gary L; White, Sarah K; Merrill, Hunter R; Gray, Gregory C

    2014-12-01

    In recent years Nigeria has experienced sporadic incursions of highly pathogenic H5N1 avian influenza among poultry. In 2008, 316 poultry-exposed agricultural workers, and 54 age-group matched non-poultry exposed adults living in the Enugu or Ebonyi States of Nigeria were enrolled and then contacted monthly for 24 months to identify acute influenza-like-illnesses. Annual follow-up sera and questionnaire data were collected at 12 and 24 months. Participants reporting influenza-like illness completed additional questionnaires, and provided nasal and pharyngeal swabs and acute and convalescent sera. Swab and sera specimens were studied for evidence of influenza A virus infection. Sera were examined for elevated antibodies against 12 avian influenza viruses by microneutralization and 3 human viruses by hemagglutination inhibition. Four (3.2%) of the 124 acute influenza-like-illness investigations yielded molecular evidence of influenza, but virus could not be cultured. Serial serum samples from five poultry-exposed subjects had a ≥4-fold change in microneutralization titers against A/CK/Nigeria/07/1132123(H5N1), with three of those having titers ≥1:80 (maximum 1:1,280). Three of the five subjects (60%) reported a preceding influenza-like illness. Hemagglutination inhibition titers were ≥4-fold increases against one of the human viruses in 260 participants. While cross-reactivity from antibodies against other influenza viruses cannot be ruled out as a partial confounder, over the course of the 2-year follow-up, at least 3 of 316 (0.9%) poultry-exposed subjects had evidence for subclinical HPAI H5N1 infections. If these data represent true infections, it seems imperative to increase monitoring for avian influenza among Nigeria's poultry and poultry workers.

  2. 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

  3. 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

  4. Molecular analysis of hemagglutinin-1 fragment of avian influenza H5N1 viruses isolated from chicken farms in Indonesia from 2008 to 2010.

    Science.gov (United States)

    Mahardika, Gusti N; Jonas, Melina; Murwijati, Theresia; Fitria, Nur; Suartha, I Nyoman; Suartini, I Gusti A A; Wibawan, I Wayan Teguh

    2016-04-15

    Highly pathogenic avian influenza virus of subtype H5N1 (AIV-H5N1) has been circulating in Indonesia since 2003. To understand the genetic diversity of these viruses, and to predict vaccine efficacy, the hemaglutinin-1 (HA-1) fragment of viruses isolated from chicken farms in Indonesia from 2008 to 2010 was sequenced and analyzed. The effects of these molecular changes were investigated in challenge experiments and HI assays of homologous and heterologous strains. Molecular analysis showed that these AIV-H5N1 isolates had evolved into three distinct sub-lineages from an ancestor circulating since 2003. Although no significant positive selection of residues was detected, 12 negatively selected sites were identified (p<0.05). Moreover, four sites showed evidence of significant episodic diversifying selection. The findings indicated complete protectivity and high HI titers with homologous strains, compared with protectivity ranging from 40 to 100% and lower HI titers with heterologous strains resulting from polymorphisms at antigenic sites. Our findings provide valuable insight into the molecular evolution of AIV and have important implications for vaccine efficacy and future vaccination strategies. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Design of new inhibitors for H5N1 avian influenza using a molecular dynamics simulation

    Science.gov (United States)

    Park, Jin Woo; Jo, Won Ho

    2008-03-01

    Recently, there has been a growing interest in the treatment of H5N1 avian influenza. One of the most widely used antiviral agents is oseltamivir. However, it has been reported that oseltamivir is not as effective against the neuraminidase subtype N1 as it is against subtypes N2 and N9. In our research we addressed this problem by designing new inhibitors and these altered inhibitor's binding affinities were calculated. In this study, we introduced chemical groups to the existing oseltamivir, so to fit into the newly discovered cavity in the subtype N1. When the binding strengths of the oseltamivir and the newly designed inhibitors for N1 were calculated to examine the drug efficiency through a molecular dynamics simulation, then compared with each other, it was found that one of the designed molecules exhibited a strong binding affinity, with more than twice the binding strength than that of oseltamivir. Since the aforementioned designed inhibitor appears to have the possibility for oral activity according to the criteria of human oral bioavailability, we propose that the inhibitor is a promising antiviral drug for H5N1 avian influenza.

  6. Genome Analysis Linking Recent European and African Influenza (H5N1) Viruses

    Science.gov (United States)

    Kingsford, Carl; Cattoli, Giovanni; Spiro, David J.; Janies, Daniel A.; Aly, Mona Mehrez; Brown, Ian H.; Couacy-Hymann, Emmanuel; De Mia, Gian Mario; Dung, Do Huu; Guercio, Annalisa; Joannis, Tony; Ali, Ali Safar Maken; Osmani, Azizullah; Padalino, Iolanda; Saad, Magdi D.; Savić, Vladimir; Sengamalay, Naomi A.; Yingst, Samuel; Zaborsky, Jennifer; Zorman-Rojs, Olga; Ghedin, Elodie; Capua, Ilaria

    2007-01-01

    To better understand the ecology and epidemiology of the highly pathogenic avian influenza virus in its transcontinental spread, we sequenced and analyzed the complete genomes of 36 recent influenza A (H5N1) viruses collected from birds in Europe, northern Africa, and southeastern Asia. These sequences, among the first complete genomes of influenza (H5N1) viruses outside Asia, clearly depict the lineages now infecting wild and domestic birds in Europe and Africa and show the relationships among these isolates and other strains affecting both birds and humans. The isolates fall into 3 distinct lineages, 1 of which contains all known non-Asian isolates. This new Euro-African lineage, which was the cause of several recent (2006) fatal human infections in Egypt and Iraq, has been introduced at least 3 times into the European-African region and has split into 3 distinct, independently evolving sublineages. One isolate provides evidence that 2 of these sublineages have recently reassorted. PMID:17553249

  7. Avian Influenza H5N1 and the Wild Bird Trade in Hanoi, Vietnam

    Directory of Open Access Journals (Sweden)

    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.

  8. Metapopulation dynamics enable persistence of influenza A, including A/H5N1, in poultry.

    Directory of Open Access Journals (Sweden)

    Parviez Rana Hosseini

    Full Text Available Highly pathogenic influenza A/H5N1 has persistently but sporadically caused human illness and death since 1997. Yet it is still unclear how this pathogen is able to persist globally. While wild birds seem to be a genetic reservoir for influenza A, they do not seem to be the main source of human illness. Here, we highlight the role that domestic poultry may play in maintaining A/H5N1 globally, using theoretical models of spatial population structure in poultry populations. We find that a metapopulation of moderately sized poultry flocks can sustain the pathogen in a finite poultry population for over two years. Our results suggest that it is possible that moderately intensive backyard farms could sustain the pathogen indefinitely in real systems. This fits a pattern that has been observed from many empirical systems. Rather than just employing standard culling procedures to control the disease, our model suggests ways that poultry production systems may be modified.

  9. Marked endotheliotropism of highly pathogenic avian influenza virus H5N1 following intestinal inoculation in cats

    NARCIS (Netherlands)

    L.A. Reperant (Leslie); M.W.G. van de Bildt (Marco); G. van Amerongen (Geert); L.M.E. Leijten (Lonneke); S. Watson (Sarah)

    2012-01-01

    textabstractHighly pathogenic avian influenza virus (HPAIV) H5N1 can infect mammals via the intestine; this is unusual since influenza viruses typically infect mammals via the respiratory tract. The dissemination of HPAIV H5N1 following intestinal entry and associated pathogenesis are largely unknow

  10. 75 FR 69046 - Notice of Determination of the High Pathogenic Avian Influenza Subtype H5N1 Status of Czech...

    Science.gov (United States)

    2010-11-10

    ... Pathogenic 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...

  11. Spatio-temporal magnitude and direction of highly pathogenic avian influenza (H5N1) outbreaks in Bangladesh

    DEFF Research Database (Denmark)

    Ahmed, Syed Sayeem Uddin; Ersbøll, Annette Kjær; Biswas, Paritosh K.;

    2011-01-01

    The number of outbreaks of HPAI-H5N1 reported by Bangladesh from 2007 through 2011 placed the country among the highest reported numbers worldwide. However, so far, the understanding of the epidemic progression, direction, intensity, persistence and risk variation of HPAI-H5N1 outbreaks over space...... and time in Bangladesh remains limited....

  12. Highly Pathogenic Avian Influenza H5N1 Clade 2.3.2.1c Virus in Lebanon, 2016.

    Science.gov (United States)

    El Romeh, Ali; Zecchin, Bianca; Fusaro, Alice; Ibrahim, Elias; El Bazzal, Bassel; El Hage, Jeanne; Milani, Adelaide; Zamperin, Gianpiero; Monne, Isabella

    2017-06-01

    We report the phylogenetic analysis of the first outbreak of H5N1 highly pathogenic avian influenza virus detected in Lebanon from poultry in April 2016. Our whole-genome sequencing analysis revealed that the Lebanese H5N1 virus belongs to genetic clade 2.3.2.1c and clusters with viruses from Europe and West Africa.

  13. Marked endotheliotropism of highly pathogenic avian influenza virus H5N1 following intestinal inoculation in cats

    NARCIS (Netherlands)

    Reperant, Leslie A; van de Bildt, Marco W G; van Amerongen, Geert; Leijten, Lonneke M E; Watson, Simon; Palser, Anne; Kellam, Paul; Eissens, Anko C; Frijlink, Hendrik W; Osterhaus, Albert D M E; Kuiken, Thijs; Frijlink, Henderik

    2012-01-01

    Highly pathogenic avian influenza virus (HPAIV) H5N1 can infect mammals via the intestine; this is unusual since influenza viruses typically infect mammals via the respiratory tract. The dissemination of HPAIV H5N1 following intestinal entry and associated pathogenesis are largely unknown. To assess

  14. Bronchointerstitial pneumonia in guinea pigs following inoculation with H5N1 high pathogenicity avian influenza virus

    Science.gov (United States)

    The H5N1 high pathogenicity avian influenza (HPAI) viruses have caused widespread disease of poultry in Asia, Africa and the Middle East, and sporadic human infections. The guinea pig model has been used to study human H3N2 and H1N1 influenza viruses, but knowledge is lacking on H5N1 HPAI virus inf...

  15. Marked endotheliotropism of highly pathogenic avian influenza virus H5N1 following intestinal inoculation in cats

    NARCIS (Netherlands)

    L.A. Reperant (Leslie); M.W.G. van de Bildt (Marco); G. van Amerongen (Geert); L.M.E. Leijten (Lonneke); S. Watson (Sarah)

    2012-01-01

    textabstractHighly pathogenic avian influenza virus (HPAIV) H5N1 can infect mammals via the intestine; this is unusual since influenza viruses typically infect mammals via the respiratory tract. The dissemination of HPAIV H5N1 following intestinal entry and associated pathogenesis are largely

  16. Spatio-temporal magnitude and direction of highly pathogenic avian influenza (H5N1) outbreaks in Bangladesh

    DEFF Research Database (Denmark)

    Ahmed, Syed Sayeem Uddin; Ersbøll, Annette Kjær; Biswas, Paritosh K.

    2011-01-01

    The number of outbreaks of HPAI-H5N1 reported by Bangladesh from 2007 through 2011 placed the country among the highest reported numbers worldwide. However, so far, the understanding of the epidemic progression, direction, intensity, persistence and risk variation of HPAI-H5N1 outbreaks over spac...

  17. 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.

  18. Seasonal influenza vaccination may mitigate the potential impact of an H5N1 pandemic

    Institute of Scientific and Technical Information of China (English)

    QIN Cheng-feng; QIN E-de

    2008-01-01

    @@ Seasonal influenza is a highly contagious, acute respiratory illness that affects people of all ages. The major pathogens, influenza A viruses, are classified into serologically defined antigenic subtypes of the hemagglutinin (HA) and neuraminidase (NA). Of 16 identified HA and 9 NA subtypes, only H1N1 and H3N2 subtypes are now circulating among humans.

  19. Produksi IgY Antivirus Avian Influenza H5N1 dan Prospek Pemanfaatannya dalam Pengebalan Pasif

    Directory of Open Access Journals (Sweden)

    I Wayan Teguh Wibawan

    2009-09-01

    Full Text Available Immunoglobulin Y (IgY in yolk has been shown in several studies to prevent both bacterial and viralinfections. This research was conducted to find evidence that IgY specific against avian influenza virus(AIV of H5N1 subtype can be produced in a large quantity in egg yolk. Laying hens were vaccinated withAI killed-vaccine (IPB-Shigeta. The IgY was purified using affinity chromatograpy technique, and anti-H5activity was measured using a standard haemaglutination inhibition (HI and agar gel immunodifusion.The concentration of IgY was calculated, and the protein pattern was detected using polyacrilamid gel(AGID electrophoresis (PAGE. Anti H5 antibody as high as 27 – 29 HI units was detected and produce aspecific line of precipitation in AGID. The concentration of IgY was 7.89 mg/ml. Purified specific IgY consistof 6 main protein bands with molecular weights ranging from 35 to 225 kD. These proteins were sensitiveto heat treatment (75oC for 30 minutes, to acid condition (pH2 as well as the pepsin and trypsin. Theseresults indicated the possibility of using specific IgY for passive immunisation to prevent AIV infection oras immunotherapeutic applications for AI treatment in humans.

  20. Avian Influenza (H5N1) Warning System using Dempster-Shafer Theory and Web Mapping

    CERN Document Server

    Maseleno, Andino

    2012-01-01

    Based on Cumulative Number of Confirmed Human Cases of Avian Influenza (H5N1) Reported to World Health Organization (WHO) in the 2011 from 15 countries, Indonesia has the largest number death because Avian Influenza which 146 deaths. In this research, the researcher built a Web Mapping and Dempster-Shafer theory as early warning system of avian influenza. Early warning is the provision of timely and effective information, through identified institutions, that allows individuals exposed to a hazard to take action to avoid or reduce their risk and prepare for effective response. In this paper as example we use five symptoms as major symptoms which include depression, combs, wattle, bluish face region, swollen face region, narrowness of eyes, and balance disorders. Research location is in the Lampung Province, South Sumatera. The researcher reason to choose Lampung Province in South Sumatera on the basis that has a high poultry population. Geographically, Lampung province is located at 103040' to 105050' East Lo...

  1. Smartphone-Based Fluorescent Diagnostic System for Highly Pathogenic H5N1 Viruses.

    Science.gov (United States)

    Yeo, Seon-Ju; Choi, Kyunghan; Cuc, Bui Thi; Hong, Nguyen Ngoc; Bao, Duong Tuan; Ngoc, Nguyen Minh; Le, Mai Quynh; Hang, Nguyen Le Khanh; Thach, Nguyen Co; Mallik, Shyam Kumar; Kim, Hak Sung; Chong, Chom-Kyu; Choi, Hak Soo; Sung, Haan Woo; Yu, Kyoungsik; Park, Hyun

    2016-01-01

    Field diagnostic tools for avian influenza (AI) are indispensable for the prevention and controlled management of highly pathogenic AI-related diseases. More accurate, faster and networked on-site monitoring is demanded to detect such AI viruses with high sensitivity as well as to maintain up-to-date information about their geographical transmission. In this work, we assessed the clinical and field-level performance of a smartphone-based fluorescent diagnostic device with an efficient reflective light collection module using a coumarin-derived dendrimer-based fluorescent lateral flow immunoassay. By application of an optimized bioconjugate, a smartphone-based diagnostic device had a two-fold higher detectability as compared to that of the table-top fluorescence strip reader for three different AI subtypes (H5N3, H7N1, and H9N2). Additionally, in a clinical study of H5N1-confirmed patients, the smartphone-based diagnostic device showed a sensitivity of 96.55% (28/29) [95% confidence interval (CI): 82.24 to 99.91] and a specificity of 98.55% (68/69) (95% CI: 92.19 to 99.96). The measurement results from the distributed individual smartphones were wirelessly transmitted via short messaging service and collected by a centralized database system for further information processing and data mining. Smartphone-based diagnosis provided highly sensitive measurement results for H5N1 detection within 15 minutes. Because of its high sensitivity, portability and automatic reporting feature, the proposed device will enable agile identification of patients and efficient control of AI dissemination.

  2. Characterization of human single-chain antibodies against highly pathogenic avian influenza H5N1 viruses: mimotope and neutralizing activity.

    Science.gov (United States)

    Yang, Jiupian; Yoshida, Reiko; Kariya, Yuki; Zhang, Xu; Hashiguchi, Shuhei; Nakashima, Toshihiro; Suda, Yasuo; Takada, Ayato; Ito, Yuji; Sugimura, Kazuhisa

    2010-10-01

    The development of new therapeutic targets and strategies to control highly pathogenic avian influenza (HPAI) H5N1 virus infection in humans is urgently needed. Neutralizing recombinant human antibodies would provide important agents for immunotherapy on human H5N1 virus infection and definition of the critical mimotope for vaccine development. In this study, we have characterized an anti-H5-specific scFv clone, 3D1 from the human-scFv-displaying phage library. 3D1 blocked the binding of H5-Fc to MDCK cells in flow cytometry and neutralized H5N1 subtype influenza A viruses in a microneutralization assay. Employing a peptide-displaying phage library, Ph.D-12, the mimotope was determined to be at #128-131 and #204-211 of H5, which are silic acid-binding regions. In consistency with this result, 3D1 binds the recombinant sugar-binding domain (#50G-#272E) produced by a baculovirus vector. The 3D1 antibody employs the germline gene VH1-23. As this antibody is the first human anti-H5 scFv clearly defined on the sugar-binding epitope, it allows us to investigate the influence of amino acid substitutions in this region on the determination of the binding specificity to either sialic acid α2,6-galactose (SA α2,6Gal) or sialic acid α2,3-galactose (SA α2,3Gal) providing new insight for the development of effective H5N1 pandemic vaccines.

  3. Sequence and epitope analysis of surface proteins of avian influenza H5N1 viruses from Asian patients

    Institute of Scientific and Technical Information of China (English)

    LI Guanglin; TAO Shiheng; WANG Xiujie

    2006-01-01

    Increasing cases of human infections with the high pathogenic avian influenza virus H5N1 have raised great concern on potential human flu pandemics caused by H5N1. The two viral surface glycoproteins, the hemagglutinin (HA) and the neuraminidase (NA) proteins, are major antigens of H5N1. Introducing new mutations on these two proteins is the major strategy used by H5N1 to expand host range and to avoid the recognition of host immune systems. We analyzed the two surface proteins of H5N1 from Asian human patients and identified many new mutation sites, including a few that were unique to certain lethal strains. We also analyzed the distribution of mutations on different epitopes of the two surface proteins. A receptor-binding site that might involve in the determination of host specificity of H5N1 was also found. Results reported here provided information for better understanding of the evolution trend of H5N1 genome in human.

  4. 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.

  5. D701N mutation in the PB2 protein contributes to the pathogenicity of H5N1 avian influenza viruses but not transmissibility in guinea pigs

    Directory of Open Access Journals (Sweden)

    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.

  6. D701N mutation in the PB2 protein contributes to the pathogenicity of H5N1 avian influenza viruses but not transmissibility in guinea pigs.

    Science.gov (United States)

    Jiao, Peirong; Wei, Liangmeng; Song, Yafen; Cui, Jin; Song, Hui; Cao, Lan; Yuan, Runyu; Luo, Kaijian; Liao, Ming

    2014-01-01

    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.

  7. Protective measures and H5N1-seroprevalence among personnel tasked with bird collection during an outbreak of avian influenza A/H5N1 in wild birds, Ruegen, Germany, 2006

    OpenAIRE

    Littmann Martina; Buda Silke; Buchholz Udo; Schweiger Brunhilde; Cai Wei; Heusler Jörg; Haas Walter

    2009-01-01

    Background: In Germany, the first outbreak of highly pathogenic avian influenza A/H5N1 occurred among wild birds on the island of Ruegen between February and April 2006. The aim of this study was to investigate the use of recommended protective measures and to measure H5N1- seroprevalence among personnel tasked with bird collection. Methods: Inclusion criteria of our study were participation in collecting wild birds on Ruegen between February and March 2006. Study participants w...

  8. Retrospective space-time analysis of H5N1 Avian Influenza emergence in Thailand

    Directory of Open Access Journals (Sweden)

    Shanmugasundaram Jothiganesh

    2010-01-01

    Full Text Available Abstract Background The highly pathogenic avian influenza (HPAI H5N1 virus remains a worldwide threat to human and animal health, while the mechanisms explaining its epizootic emergence and re-emergence in poultry are largely unknown. Data from Thailand, a country that experienced significant epidemics in poultry and has recorded suspicious cases of HPAI on a daily basis since 2004, are used here to study the process of emergence. A spatial approach is employed to describe all HPAI H5N1 virus epizootics from 2004 to 2008 and to characterize the pattern of emergence: multiple independent introductions of the virus followed by moderate local spread vs. very rare emergences followed by strong local spread and rare long range diffusion jumps. Sites where epizootics originate (by foreign introduction, local persistence, or long range jump were selected from those to which the disease subsequently spreads using a filter based on relative date and position. The spatial distribution of these selected foci was statistically analyzed, and to differentiate environmental factors from long range diffusion, we investigate the relationship of these foci with environmental exposure factors and with rearing characteristics. Results During each wave of epizootics, the temporal occurrence of cases did not show a temporal interruption of more than a week. All foci were globally clustered; i.e., more than 90% of cases had a previous case within a 10 km range and a 21 day period of time, showing a strong local spread. We were able to estimate 60 km as the maximum distance for the local farm to farm dissemination process. The remaining "emergent" cases have occurred randomly over Thailand and did not show specific location, clusters, or trends. We found that these foci are not statistically related to specific environmental conditions or land cover characteristics, and most of them may be interpreted as long range diffusion jumps due to commercial practices

  9. Impact of the implementation of rest days in live bird markets on the dynamics of H5N1 highly pathogenic avian influenza.

    Science.gov (United States)

    Fournié, G; Guitian, F J; Mangtani, P; Ghani, A C

    2011-08-01

    Live bird markets (LBMs) act as a network 'hub' and potential reservoir of infection for domestic poultry. They may therefore be responsible for sustaining H5N1 highly pathogenic avian influenza (HPAI) virus circulation within the poultry sector, and thus a suitable target for implementing control strategies. We developed a stochastic transmission model to understand how market functioning impacts on the transmission dynamics. We then investigated the potential for rest days-periods during which markets are emptied and disinfected-to modulate the dynamics of H5N1 HPAI within the poultry sector using a stochastic meta-population model. Our results suggest that under plausible parameter scenarios, HPAI H5N1 could be sustained silently within LBMs with the time spent by poultry in markets and the frequency of introduction of new susceptible birds' dominant factors determining sustained silent spread. Compared with interventions applied in farms (i.e. stamping out, vaccination), our model shows that frequent rest days are an effective means to reduce HPAI transmission. Furthermore, our model predicts that full market closure would be only slightly more effective than rest days to reduce transmission. Strategies applied within markets could thus help to control transmission of the disease.

  10. Investigation of outbreaks of highly pathogenic H5N1 avian influenza in waterfowl and wild birds in Hong Kong in late 2002.

    Science.gov (United States)

    Ellis, Trevor M; Bousfield, R Barry; Bissett, Lucy A; Dyrting, Kitman C; Luk, Geraldine S M; Tsim, S T; Sturm-Ramirez, Katharine; Webster, Robert G; Guan, Yi; Malik Peiris, J S

    2004-10-01

    Outbreaks of highly pathogenic H5N1 avian influenza have occurred in Hong Kong in chickens and other gallinaceous poultry in 1997, 2001, twice in 2002 and 2003. High mortality rates were seen in gallinaceous birds but not in domestic or wild waterfowl or other wild birds until late 2002 when highly pathogenic H5N1 avian influenza occurred in waterfowl (geese, ducks and swans), captive Greater Flamingo (Phoenicopterus ruber) and other wild birds (Little Egret Egretta garzetta) at two waterfowl parks and from two dead wild Grey Heron (Ardea cinerea) and a Black-headed Gull (Larus ridibundus) in Hong Kong. H5N1 avian influenza virus was also isolated from a dead feral pigeon (Columba livia) and a dead tree sparrow (Passer montanus) during the second outbreak. The first waterfowl outbreak was controlled by immediate strict quarantine and depopulation 1 week before the second outbreak commenced. Control measures implemented for the second outbreak included strict isolation, culling, increased sanitation and vaccination. Outbreaks in gallinaceous birds occurred in some live poultry markets concurrently with the second waterfowl outbreak, and infection on a chicken farm was detected 1 week after the second waterfowl park outbreak was detected, on the same day the second grey heron case was detected. Subsequent virus surveillance showed the outbreaks had been contained.

  11. Transmission of the highly pathogenic avian influenza virus H5N1 within flocks during the 2004 epidemic in Thailand.

    Science.gov (United States)

    Tiensin, Thanawat; Nielen, Mirjam; Vernooij, Hans; Songserm, Thaweesak; Kalpravidh, Wantanee; Chotiprasatintara, Sirikan; Chaisingh, Arunee; Wongkasemjit, Surapong; Chanachai, Karoon; Thanapongtham, Weerapong; Srisuvan, Thinnarat; Stegeman, Arjan

    2007-12-01

    This present study is the first to quantify the transmission of avian influenza virus H5N1 within flocks during the 2004 epidemic in Thailand. It uses the flock-level mortality data to estimate the transmission-rate parameter ( beta ) and the basic reproduction number (R(0)). The point estimates of beta varied from 2.26/day (95% confidence interval [CI], 2.01-2.55) for a 1-day infectious period to 0.66/day (95% CI, 0.50-0.87) for a 4-day infectious period, whereas the accompanying R(0) varied from 2.26 (95% CI, 2.01-2.55) to 2.64 (95% CI, 2.02-3.47). Although the point estimates of beta of backyard chickens and fighting cocks raised together were lower than those of laying hens and broiler chickens, this difference was not statistically significant. These results will enable us to assess the control measures in simulation studies. They also indicate that, for the elimination of the virus, a critical proportion of the susceptible poultry population in a flock (i.e., 80% of the population) needs to be vaccinated.

  12. Evolutionary features of influenza A/H5N1 virus populations in Egypt: poultry and human health implications.

    Science.gov (United States)

    Naguib, Mahmoud M; Abdelwhab, E M; Harder, Timm C

    2016-07-01

    Since 2006, in Egypt, highly pathogenic avian influenza virus (HPAIV) H5N1 has established endemic status in poultry. Bayesian evolutionary analysis sampling trees suggested an introduction date in the third quarter of 2005. Evolutionary dynamics using Bayesian analysis showed that H5N1 viruses of clade 2.2.1.1 evolved at higher rates than those of clade 2.2.1.2. Bayesian skyline plot analysis of the HA gene of 840 and NA gene of 401 Egyptian H5N1 viruses from 2006-2015 identified two waves of viral population expansion correlating with the stepwise emergence of the 2.2.1.1 variant lineage in 2008 and with the newly emerging 2.2.1.2 cluster in late 2014. H5N1 infections in human hosts in 2014-2015 were statistically linked to a contemporary poultry outbreak.

  13. 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.

  14. Molecular analysis of Hemagglutinin Gen of Highly Pathogenic Avian Influenza of H5N1 Subtype Isolated from Waterfowls

    National Research Council Canada - National Science Library

    R Susanti; Retno D Soejoedono; I Gusti Ngurah K Mahardika; I Wayan T Wibawan; Maggy T Suhartono

    2008-01-01

    Avian influenza viruses (AIV) subtype H5N1 isolated from waterfowls in West Java pose the known characteristic of highly pathogenic strains, with polybasic amino acid sequence of cleavage site QRERRRKKR and QRESRRKKR...

  15. Prediction and identification of T cell epitopes in the H5N1 influenza virus nucleoprotein in chicken.

    Directory of Open Access Journals (Sweden)

    Yanxia Hou

    Full Text Available T cell epitopes can be used for the accurate monitoring of avian influenza virus (AIV immune responses and the rational design of vaccines. No T cell epitopes have been previously identified in the H5N1 AIV virus nucleoprotein (NP in chickens. For the first time, this study used homology modelling techniques to construct three-dimensional structures of the peptide-binding domains of chicken MHC class Ι molecules for four commonly encountered unique haplotypes, i.e., B4, B12, B15, and B19. H5N1 AIV NP was computationally parsed into octapeptides or nonapeptides according to the peptide-binding motifs of MHC class I molecules of the B4, B12, B15 and B19 haplotypes. Seventy-five peptide sequences were modelled and their MHC class I molecule-binding abilities were analysed by molecular docking. Twenty-five peptides (Ten for B4, six for B12, two for B15, and seven for B19 were predicted to be potential T cell epitopes in chicken. Nine of these peptides and one unrelated peptide were manually synthesized and their T cell responses were tested in vitro. Spleen lymphocytes were collected from SPF chickens that had been immunised with a NP-expression plasmid, pCAGGS-NP, and they were stimulated using the synthesized peptides. The secretion of chicken IFN-γ and the proliferation of CD8(+ T cells were tested using an ELISA kit and flow cytometry, respectively. The significant secretion of chicken IFN-γ and proliferation of CD8(+ T lymphocytes increased by 13.7% and 11.9% were monitored in cells stimulated with peptides NP(89-97 and NP(198-206, respectively. The results indicate that peptides NP(89-97 (PKKTGGPIY and NP(198-206 (KRGINDRNF are NP T cell epitopes in chicken of certain haplotypes. The method used in this investigation is applicable to predicting T cell epitopes for other antigens in chicken, while this study also extends our understanding of the mechanisms of the immune response to AIV in chicken.

  16. Rapid Emergence of Highly Pathogenic Avian Influenza Subtypes from a Subtype H5N1 Hemagglutinin Variant.

    Science.gov (United States)

    de Vries, Erik; Guo, Hongbo; Dai, Meiling; Rottier, Peter J M; van Kuppeveld, Frank J M; de Haan, Cornelis A M

    2015-05-01

    In 2014, novel highly pathogenic avian influenza A H5N2, H5N5, H5N6, and H5N8 viruses caused outbreaks in Asia, Europe, and North America. The H5 genes of these viruses form a monophyletic group that evolved from a clade 2.3.4 H5N1 variant. This rapid emergence of new H5Nx combinations is unprecedented in the H5N1 evolutionary history.

  17. Avian influenza (H5N1 virus of clade 2.3.2 in domestic poultry in India.

    Directory of Open Access Journals (Sweden)

    Shanmuga Nagarajan

    Full Text Available South Asia has experienced regular outbreaks of H5N1 avian influenza virus since its first detection in India and Pakistan in February, 2006. Till 2009, the outbreaks in this region were due to clade 2.2 H5N1 virus. In 2010, Nepal reported the first outbreak of clade 2.3.2 virus in South Asia. In February 2011, two outbreaks of H5N1 virus were reported in the State of Tripura in India. The antigenic and genetic analyses of seven H5N1 viruses isolated during these outbreaks were carried out. Antigenic analysis confirmed 64 to 256-fold reduction in cross reactivity compared with clade 2.2 viruses. The intravenous pathogenicity index of the isolates ranged from 2.80-2.95 indicating high pathogenicity to chickens. Sequencing of all the eight gene-segments of seven H5N1 viruses isolated in these outbreaks was carried out. The predicted amino acid sequence analysis revealed high pathogenicity to chickens and susceptibility to the antivirals, amantadine and oseltamivir. Phylogenetic analyses indicated that these viruses belong to clade 2.3.2.1 and were distinct to the clade 2.3.2.1 viruses isolated in Nepal. Identification of new clade 2.3.2 H5N1 viruses in South Asia is reminiscent of the introduction of clade 2.2 viruses in this region in 2006/7. It is now important to monitor whether the clade 2.3.2.1 is replacing clade 2.2 in this region or co-circulating with it. Continued co-circulation of various subclades of the H5N1 virus which are more adapted to land based poultry in a highly populated region such as South Asia increases the risk of evolution of pandemic H5N1 strains.

  18. 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.

    2009-01-01

    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.

  19. Clinical characteristics of 26 human cases of highly pathogenic avian influenza A (H5N1 virus infection in China.

    Directory of Open Access Journals (Sweden)

    Hongjie Yu

    Full Text Available BACKGROUND: While human cases of highly pathogenic avian influenza A (H5N1 virus infection continue to increase globally, available clinical data on H5N1 cases are limited. We conducted a retrospective study of 26 confirmed human H5N1 cases identified through surveillance in China from October 2005 through April 2008. METHODOLOGY/PRINCIPAL FINDINGS: Data were collected from hospital medical records of H5N1 cases and analyzed. The median age was 29 years (range 6-62 and 58% were female. Many H5N1 cases reported fever (92% and cough (58% at illness onset, and had lower respiratory findings of tachypnea and dyspnea at admission. All cases progressed rapidly to bilateral pneumonia. Clinical complications included acute respiratory distress syndrome (ARDS, 81%, cardiac failure (50%, elevated aminotransaminases (43%, and renal dysfunction (17%. Fatal cases had a lower median nadir platelet count (64.5 x 10(9 cells/L vs 93.0 x 10(9 cells/L, p = 0.02, higher median peak lactic dehydrogenase (LDH level (1982.5 U/L vs 1230.0 U/L, p = 0.001, higher percentage of ARDS (94% [n = 16] vs 56% [n = 5], p = 0.034 and more frequent cardiac failure (71% [n = 12] vs 11% [n = 1], p = 0.011 than nonfatal cases. A higher proportion of patients who received antiviral drugs survived compared to untreated (67% [8/12] vs 7% [1/14], p = 0.003. CONCLUSIONS/SIGNIFICANCE: The clinical course of Chinese H5N1 cases is characterized by fever and cough initially, with rapid progression to lower respiratory disease. Decreased platelet count, elevated LDH level, ARDS and cardiac failure were associated with fatal outcomes. Clinical management of H5N1 cases should be standardized in China to include early antiviral treatment for suspected H5N1 cases.

  20. Predominance and geo-mapping of avian influenza H5N1 in poultry sectors in Egypt

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    Abdelsatar Arafa

    2016-11-01

    Full Text Available Highly pathogenic avian influenza (HPAI virus of the H5N1 subtype has been enzootic in the Egyptian poultry with significant human infections since 2008. This work evaluates the epidemiological and virological information from February 2006 to May 2015 in spatial and temporal terms. Only data with confirmed HPAI H5N1 sub-type were collected, and matched with the epidemiological data from various spatially and temporally-dispersed surveillances implemented between 2006 and 2015. Spatio-temporal analysis was conducted on a total of 3338 confirmed H5N1 HPAI poultry disease outbreaks and outputs described based on transmission patterns, poultry species, production types affected, trade, geographic and temporal distributions in Egypt. The H5N1 virus persists in the Egyptian poultry displaying a seasonal pattern with peak prevalence between January and March. There was no specific geographic pattern, but chickens and ducks were more affected. However, relatively higher disease incidences were recorded in the Nile Delta. Phylogenetic studies of the haemagglutinin gene sequences of H5N1 viruses indicated that multiple clusters circulated between 2006 and 2015, with significant deviations in circulation. Epidemiological dynamics of HPAI has changed with the origins of majority of outbreaks shifted to household poultry. The persistence of HPAI H5N1 in poultry with recurrent and sporadic infections in humans can influence virus evolution spatio-temporally. Household poultry plays significant roles in the H5N1 virus transmission to poultry and humans, but the role of commercial poultry needs further clarifications. While poultry trading supports the persistence and transmission of H5N1, the role of individual species may warrant further investigation. Surveillance activities, applying a multi-sectoral approach, are recommended.

  1. Genetic Characterization of Clade 2.3.2.1 Avian Influenza A(H5N1) Viruses, Indonesia, 2012

    Science.gov (United States)

    Hartawan, Risza; Pudjiatmoko; Wibawa, Hendra; Hardiman; Balish, Amanda; Donis, Ruben; Davis, C. Todd; Samaan, Gina

    2014-01-01

    After reports of unusually high mortality rates among ducks on farms in Java Island, Indonesia, in September 2012, influenza A(H5N1) viruses were detected and characterized. Sequence analyses revealed all genes clustered with contemporary clade 2.3.2.1 viruses, rather than enzootic clade 2.1.3 viruses, indicating the introduction of an exotic H5N1 clade into Indonesia. PMID:24656213

  2. Radiological and clinical course of pneumonia in patients with avian influenza H5N1

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    Bay, Ali [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey)]. E-mail: bayalibay@yahoo.com; Etlik, Omer [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Oner, A. Faik [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey); Unal, Ozkan [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Arslan, Halil [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Bora, Aydin [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Davran, Ramazan [Yuzuncu Yil University, Faculty of Medicine, Department of Radiology, Van (Turkey); Yuca, Sevil Ari [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey); Dogan, Murat [Yuzuncu Yil University, Faculty of Medicine, Department of Pediatrics, Van (Turkey)

    2007-02-15

    Introduction: We evaluated chest X-ray and clinical findings of patients with lower respiratory tract infection due to influenza H5N1 and presented the radiological findings and clinical course of the infection. Materials and methods: Between December 2005 and February 2006, eight hospitalized patients (median age 10, 5-15 years) with avian-flu were evaluated in this study. All patients were evaluated with chest X-ray and four of them with CT scan. Post mortem pathological characterization were also available for three of the patients. Results: A rapidly progressive pneumonia with high mortality rate was observed especially for cases with late admission. The major radiologic abnormalities were extensive pneumonic infiltration with segmental and multifocal distribution, mostly located in lower zones of the lung. No pleural effusion and hilar lymphadenopathy was noted. Conclusion: Avian flu may be presented as rapidly progressive pneumonia. The chest radiography has an important role in diagnosis and should be obtained daily because of rapid change of the findings that may necessitate prompt action.

  3. The antigenic property of the H5N1 avian influenza viruses isolated in central China

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    Zou Wei

    2012-08-01

    Full Text Available Abstract Background Three influenza pandemics outbroke in the last century accompanied the viral antigen shift and drift, resulting in the change of antigenic property and the low cross protective ability of the existed antibody to the newly emerged pandemic virus, and eventually the death of millions of people. The antigenic characterizations of the viruses isolated in central China in 2004 and 2006–2007 were investigated in the present study. Results Hemagglutinin inhibition assay and neutralization assay displayed differential antigenic characteristics of the viruses isolated in central China in two periods (2004 and 2006–2007. HA genes of the viruses mainly located in two branches in phylogeny analysis. 53 mutations of the deduced amino acids of the HA genes were divided into 4 patterns. Mutations in pattern 2 and 3 showed the main difference between viruses isolated in 2004 and 2006–2007. Meanwhile, most amino acids in pattern 2 and 3 located in the globular head of the HA protein, and some of the mutations evenly distributed at the epitope sites. Conclusions The study demonstrated that a major antigenic drift had occurred in the viruses isolated in central China. And monitoring the antigenic property should be the priority in preventing the potential pandemic of H5N1 avian influenza virus.

  4. Survival of H5N1 influenza virus in water and its inactivation by chemical methods.

    Science.gov (United States)

    Mihai, Maria Elena; Tecu, Cristina; Ivanciuc, Alina Elena; Necula, Gheorghe; Lupulescu, Emilia; Onu, Adrian

    2011-01-01

    The ability of H5N1 Avian Influenza Virus (AIV) to survive in surface water has been assessed in experimental laboratory conditions, based on non-pathogenic avian reassortant model, by titration of infectivity (TCID50) at different time intervals, in three different types of water. The effect of different chemicals on AIV's survival was assessed using the same type of experimental model. After exposure to the chemical, followed by growth on a suitable substrate, the AIV was quantified by a real-time quantitative reverse transcriptase PCR (qRT-PCR). The reassortant virus persisted, and remained infective in aquatic environments, for 12 days at 22-35 degrees C and up to 20 days at 4 degrees C, irrespective of the type of water, supporting the hypothesis of a potential risk for transmitting the virus among birds and contaminating the household water via common sources of water. A significant decrease for AIV persistence models was recorded for sea water, after 12 days, at 35 degrees C. An effective inactivation has been shown when using commercially available products based on glutaraldehyde and penta potassium bis (peroxy mono sulphate) bis(sulphate), respectively. This rapid and safe method for decontamination, developed in this study, might be helpful in implementation of biosafety measures in laboratory and farms against AIV.

  5. Phylogenetic and pathogenic analyses of avian influenza A H5N1 viruses isolated from poultry in Vietnam.

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    Dongming Zhao

    Full Text Available Despite great efforts to control the infection of poultry with H5N1 viruses, these pathogens continue to evolve and spread in nature, threatening public health. Elucidating the characteristics of H5N1 avian influenza virus will benefit disease control and pandemic preparation. Here, we sequenced the genomes of 15 H5N1 avian influenza viruses isolated in Vietnam in 2006 and 2007 and performed phylogenetic analyses to compare these sequences with those of other viruses available in the public databases. Molecular characterization of the H5N1 viruses revealed that seven genetically distinct clades of H5N1 viruses have appeared in Vietnam. Clade 2.3.4 viruses existed in Vietnam as early as 2005. Fifteen viruses isolated during 2006 and 2007 belonged to clade 1 and clade 2.3.4, and were divided into five genotypes. Reassortants between the clade 1 and clade 2.3.4 viruses were detected in both North and South Vietnam. We also assessed the replication and pathogenicity of these viruses in mice and found that these isolates replicated efficiently and exhibited distinct virulence in mice. Our results provide important information regarding the diversity of H5N1 viruses in nature.

  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. Satellite-marked waterfowl reveal migratory connection between H5N1 outbreak areas in China and Mongolia

    Science.gov (United States)

    Prosser, D.J.; Takekawa, J.Y.; Newman, S.H.; Yan, B.; Douglas, D.C.; Hou, Y.; Xing, Z.; Zhang, Dongxiao; Li, T.; Li, Y.; Zhao, D.; Perry, W.M.; Palm, E.C.

    2009-01-01

    The role of wild birds in the spread of highly pathogenic avian influenza H5N1 has been greatly debated and remains an unresolved question. However, analyses to determine involvement of wild birds have been hindered by the lack of basic information on their movements in central Asia. Thus, we initiated a programme to document migrations of waterfowl in Asian flyways to inform hypotheses of H5N1 transmission. As part of this work, we studied migration of waterfowl from Qinghai Lake, China, site of the 2005 H5N1 outbreak in wild birds. We examined the null hypothesis that no direct migratory connection existed between Qinghai Lake and H5N1 outbreak areas in central Mongolia, as suggested by some H5N1 phylogeny studies. We captured individuals in 2007 from two of the species that died in the Qinghai Lake outbreaks and marked them with GPS satellite transmitters: Bar-headed Geese Anser indicus (n = 14) and Ruddy Shelduck Tadorna ferruginea (n = 11). Three of 25 marked birds (one Goose and two Shelducks) migrated to breeding grounds near H5N1 outbreak areas in Mongolia. Our results describe a previously unknown migratory link between the two regions and offer new critical information on migratory movements in the region. ?? 2009 British Ornithologists' Union.

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

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    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%.

  9. Lethal infection by a novel reassortant H5N1 avian influenza A virus in a zoo-housed tiger.

    Science.gov (United States)

    He, Shang; Shi, Jianzhong; Qi, Xian; Huang, Guoqing; Chen, Hualan; Lu, Chengping

    2015-01-01

    In early 2013, a Bengal tiger (Panthera tigris) in a zoo died of respiratory distress. All specimens from the tiger were positive for HPAI H5N1, which were detected by real-time PCR, including nose swab, throat swab, tracheal swab, heart, liver, spleen, lung, kidney, aquae pericardii and cerebrospinal fluid. One stain of virus, A/Tiger/JS/1/2013, was isolated from the lung sample. Pathogenicity experiments showed that the isolate was able to replicate and cause death in mice. Phylogenetic analysis indicated that HA and NA of A/Tiger/JS/1/2013 clustered with A/duck/Vietnam/OIE-2202/2012 (H5N1), which belongs to clade 2.3.2.1. Interestingly, the gene segment PB2 shared 98% homology with A/wild duck/Korea/CSM-28/20/2010 (H4N6), which suggested that A/Tiger/JS/1/2013 is a novel reassortant H5N1 subtype virus. Immunohistochemical analysis also confirmed that the tiger was infected by this new reassortant HPAI H5N1 virus. Overall, our results showed that this Bengal tiger was infected by a novel reassortant H5N1, suggesting that the H5N1 virus can successfully cross species barriers from avian to mammal through reassortment.

  10. Continual Antigenic Diversification in China Leads to Global Antigenic Complexity of Avian Influenza H5N1 Viruses

    Science.gov (United States)

    Peng, Yousong; Li, Xiaodan; Zhou, Hongbo; Wu, Aiping; Dong, Libo; Zhang, Ye; Gao, Rongbao; Bo, Hong; Yang, Lei; Wang, Dayan; Lin, Xian; Jin, Meilin; Shu, Yuelong; Jiang, Taijiao

    2017-01-01

    The highly pathogenic avian influenza (HPAI) H5N1 virus poses a significant potential threat to human society due to its wide spread and rapid evolution. In this study, we present a comprehensive antigenic map for HPAI H5N1 viruses including 218 newly sequenced isolates from diverse regions of mainland China, by computationally separating almost all HPAI H5N1 viruses into 15 major antigenic clusters (ACs) based on their hemagglutinin sequences. Phylogenetic analysis showed that 12 of these 15 ACs originated in China in a divergent pattern. Further analysis of the dissemination of HPAI H5N1 virus in China identified that the virus’s geographic expansion was co-incident with a significant divergence in antigenicity. Moreover, this antigenic diversification leads to global antigenic complexity, as typified by the recent HPAI H5N1 spread, showing extensive co-circulation and local persistence. This analysis has highlighted the challenge in H5N1 prevention and control that requires different planning strategies even inside China. PMID:28262734

  11. Ecologic risk factor investigation of clusters of avian influenza A (H5N1) virus infection in Thailand.

    Science.gov (United States)

    Tiensin, Thanawat; Ahmed, Syed Sayeem Uddin; Rojanasthien, Suvichai; Songserm, Thaweesak; Ratanakorn, Parntep; Chaichoun, Kridsada; Kalpravidh, Wantanee; Wongkasemjit, Surapong; Patchimasiri, Tuangthong; Chanachai, Karoon; Thanapongtham, Weerapong; Chotinan, Suwit; Stegeman, Arjan; Nielen, Mirjam

    2009-06-15

    This study was conducted to investigate space and time clusters of highly pathogenic avian influenza A (H5N1) virus infection and to determine risk factors at the subdistrict level in Thailand. Highly pathogenic avian influenza A (H5N1) was diagnosed in 1890 poultry flocks located in 953 subdistricts during 2004-2007. The ecologic risk for H5N1 virus infection was assessed on the basis of a spatial-based case-control study involving 824 case subdistricts and 3296 control subdistricts from 6 study periods. Risk factors investigated in clustered areas of H5N1 included human and animal demographic characteristics, poultry production systems, and wild birds and their habitats. Six variables remained statistically significant in the final model: flock density of backyard chickens (odds ratio [OR], 0.98), flock density of fighting cocks (OR, 1.02), low and high human density (OR, 0.60), presence of quail flocks (OR, 1.21), free-grazing duck flocks (OR, 2.17), and a poultry slaughterhouse (OR, 1.33). We observed a strong association between subdistricts with H5N1 virus-infected poultry flocks and evidence of prior and concomitant H5N1 infection in wild birds in the same subdistrict.

  12. Identifikasi Secara Serologi Galur Virus Flu Burung Subtipe H5N1 Clade 2.1.3 dan Clade 2.3.2 pada Ayam Petelur (SEROLOGICAL IDENTIFICATION OF AVIAN INFLUENZA STRAIN VIRUS SUBTYPE H5N1 CLADE 2.1.3 AND CLADE 2.3.2 FROM LAYER

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    Aprilia Kusumastuti

    2015-10-01

    Full Text Available The aim of the study was to know avian influenza (AI infection in field by using serology test in threemarketing area of AI vaccines. Haemagglutination inhibition methode was used in this test. There werefour antigen strains of AI subtype H5N1 clade 2.1.3 (AIstrainA/Chicken/West Java/PWT-WIJ/2006, AIstrain A/Chicken/Garut/BBVW-223/2007, AI strain A/Chicken/West Java-Nagrak/30/2007, and AI strainA/Chicken/Pekalongan/BBVW-208/2007 and 2 antigen strains of AI subtype H5N1 clade 2.3.2 (AI strainA/duck/Sukoharjo/BBVW-1428-9/2012 and AI strain A/duck/Sleman/BBVW-1463-10/2012 was used inthis study for HI test. The result presents that 93,33% chicken farms in three marketing area of PT. SanbioLaboratories have positive antibody titre to AI subtype H5N1 clade 2.1.3. This titre may be obtained fromAI clade 2.1.3 vaccination. From 15 samples, 92,86% are positive to AI subtype H5N1 clade 2.3.2A/duck/Sukoharjo/BBVW-1428-9/2012 and 92,31% are positive to A/duck/Sleman/BBVW-1463-10/2012 evenwithout AI clade 2.3.2 vaccination. This antibody titre may be obtained from AI clade 2.1.3 vaccine crossprotection or field infection.

  13. Expression of H5N1 influenza virus hemagglutinin protein fused with protein transduction domain in an alphavirus replicon system.

    Science.gov (United States)

    Yang, Shi-gui; Wo, Jian-er; Li, Min-wei; Mi, Fen-fang; Yu, Cheng-bo; Lv, Guo-liang; Cao, Hong-Cui; Lu, Hai-feng; Wang, Bao-hong; Zhu, Hanping; Li, Lan-Juan

    2010-01-01

    Alphavirus replicons, in which structural protein genes are replaced by heterologous genes, express high levels of the heterologous proteins. On the basis of the potencies of replicons to self-replicate and express foreign proteins and the remarkable intercellular transport property of VP22, a novel alphavirus Semliki Forest virus (SFV) replicon system of VP22 fused with a model antigen, hemagglutinin (HA), of the human-avian H5N1 influenza virus, was explored in this study. Further, replicon particles expressing HA, VP22, and enhanced green fluorescent protein (EGFP) individually were used as controls. By flow cytometry based on the analysis of transfection efficiency, SFV-EGFP replicon particle titer was 1.13 x 10(7)transducing units (TU)/ml. The titers of SFV-HA, SFV-VP22 and SFV-VP22-HA replicon particles, which were titrated by using SFV-EGFP replicon particles, were 1.42 x 10(7), 3.23 x 10(7), and 1.01 x 10(7)TU/ml, respectively. HA and VP22-HA expression was observed in SFV-HA- and SFV-VP22-HA-transfected BHK-21 cells, respectively. Immunofluorescence staining revealed that the fluorescence intensity in the SFV-VP22-HA-transfected BHK-21 cells was more than that in the SFV-HA-transfected BHK-21 cells. Both SFV-VP22-HA and SFV-HA replicon particles presented a promising approach for developing vaccines against human-avian influenza. VP22-HA fusion protein with similar trafficking properties may also enhance vaccine potency.

  14. Isolasi dan Identifikasi Virus Avian Influenza Subtipe H5N1 pada Unggas di Pasar Tradisional Semarang

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    Farikhul Ulum

    2013-09-01

    Full Text Available Meningkatnya kasus infeksi virus Avian Influenza (AI subtipe H5N1 atau lebih dikenal dengan flu burung yang menyebabkan kematian pada manusia sangat dikhawatirkan dapat menular dari manusia ke manusia. Penelitian ini bertujuan untuk mendapatkan isolat virus Avian Influenza subtipe H5N1 pada unggas yang diperjualbelikan di pasar tradisional di Semarang. Sebanyak 55 sampel usap kloaka diambil dari unggas sehat dan belum divaksin di 6 pasar tradisional Kota Semarang. Inokulum ditumbuhkan pada telur ayam berembrio specific pathogen free (TAB-SPF umur sembilan hari. Kemudian telur diinkubasikan selama 4 hari. Cairan alantois dipanen dan diuji kemampuannya mengaglutinasi sel darah merah. Cairan alantois yang menunjukkan aktivitas hemaglutinasi, selanjutnya diekstraksi RNA-nya dan diidentifikasi VAI subtipe H5N1 dengan metode Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR menggunakan primer spesifik H5 dan primer N1. Kemudian DNA hasil RT-PCR dianalisis dengan teknik elektroforesis. Hasil penelitian menunjukkan bahwa terdapat 4 isolat positif VAI subtipe H5N1 dengan sebaran 2 isolat dari sampel yang berasal dari pasar Mangkang, 1 isolat dari pasar Rejomulyo dan 1 isolat dari pasar Karimata. Berdasarkan hasil penelitian dan pembahasan dapat disimpulkan bahwa unggas yang diperjualbelikan di pasar tradisional di Kota Semarang ada yang terinfeksi VAI subtipe H5N1.The increasing cases of viral infection of Avian Influenza (AI H5N1 subtype or more commonly known as bird flu that causes death in humans very feared to spread from human to human. The aim of this research was to obtain isolates of Avian Influenza virus (AIV subtype H5N1 that marketable in traditional markets in Semarang. A total of 55 cloacal swab samples taken from healthy and unvaccinated fowl in the 6 traditional market in Semarang. Inoculum was grown in embryonated chicken eggs specific pathogen free (SPF TAB nine days. Then the eggs were incubated for 4 days. Allantoic fluids were

  15. 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

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    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.

  16. Analysis of hemagglutinin variance of avian influenza viru (H5N1)%禽流感病毒H5N1亚型血凝素氨基酸序列的变异分析

    Institute of Scientific and Technical Information of China (English)

    王国戗; 牛菊霞; 艾敏

    2009-01-01

    目的 研究不同来源禽流感病毒H5N1亚型血凝素(hemagglutinin,HA)氨基酸序列的变异及变异规律. 方法 以GenBank公开的禽流感病毒H5N1亚型HA氨基酸序列为材料,利用生物信息学的手段分析其同源性及氨基酸变异规律. 结果 46个禽流感病毒H5N1亚型HA氨基酸序列之间的同源性为90%~100%;同一地区来源的氨基酸之间的同源性大于异地来源的同源性;在H5N1亚型HA氨基酸序列中,天冬酰氨酸、丝氨酸、苏氨酸、精氨酸和天门冬氨酸最常发生突变. 结论 禽流感病毒H5N1亚型血凝素氨基酸序列的变异呈现出一定的规律.

  17. Estimating the sensitivity of passive surveillance for HPAI H5N1 in Bayelsa state, Nigeria.

    Science.gov (United States)

    Ojimelukwe, Agatha E; Prakarnkamanant, Apisit; Rushton, Jonathan

    2016-07-01

    This study identified characteristics of poultry farming with a focus on practices that affect the detection of HPAI; and estimated the system sensitivity of passive surveillance for HPAI H5N1 in commercial and backyard chicken farms in Bayelsa-State, Nigeria. Field studies were carried out in Yenegoa and Ogbia local government areas in Bayelsa state. Willingness to report HPAI was highest in commercial poultry farms (13/13) than in Backyard farms (8/13). Poor means of dead bird disposal was common to both commercial and backyard farms. Administering some form of treatment to sick birds without prior consultation with a professional was higher in backyard farms (8/13) than in commercial farms (4/13). Consumption of sick birds was reported in 4/13 backyard farms and sale of dead birds was recorded in one commercial farm. The sensitivity of passive surveillance for HPAI was assessed using scenario tree modelling. A scenario tree model was developed and applied to estimate the sensitivity, i.e. the probability of detecting one or more infected chicken farms in Bayelsa state at different levels of disease prevalence. The model showed a median sensitivity of 100%, 67% and 23% for detecting HPAI by passive surveillance at a disease prevalence of 0.1%, a minimum of 10 and 3 infected poultry farms respectively. Passive surveillance system sensitivity at a design prevalence of 10 infected farms is increasable up to 86% when the disease detection in backyard chicken farms is enhanced. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. 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.

  19. 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.

  20. 感染人类的禽流感病毒A(H5N1)研究进展%Update on avian influenza A(H5N1)virus infection in humans

    Institute of Scientific and Technical Information of China (English)

    钟晓琴; 王关嵩

    2009-01-01

    @@ 禽流感病毒A(H5N1)[avian influenza(H5N1)viruses]之前一直存在于鸟类,但却能导致人类疾病,并且具有高致死性和广泛流行的威胁.本文在综合了第二届世界卫生组织(World Health Organization,WHO)感染人类禽流感病毒A(H5N1)临床诊断咨询会议公布的研究信息[2]基础上,对2005年的报告[1]进行了更新.

  1. The Threat of H5N1 Avian Influenza and Global Preparedness%H5N1禽流感的威胁与全球应对

    Institute of Scientific and Technical Information of China (English)

    田德桥; 郑涛

    2007-01-01

    当前H5N1禽流感在迁徙禽类、家禽中的暴发,以及越来越多的人感染病例的发生,使流感全球大流行的可能性持续存在.简要综述了H5N1禽流感在鸟类和其他动物中的暴发情况,H5N1禽流感的人感染病例,以及全球禽流感应对计划及疫苗、药物、病原体基础研究的进展.

  2. Knowledge, attitudes, practices and emotional reactions among residents of avian influenza (H5N1 hit communities in Vietnam.

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    Toshie Manabe

    Full Text Available BACKGROUND: Awareness of individuals' knowledge and predicting their behavior and emotional reactions is crucial when evaluating clinical preparedness for influenza pandemics with a highly pathogenic virus. Knowledge, attitude, and practice (KAP relating to avian influenza (H5N1 virus infection among residents in communities where H5N1 patients occurred in Vietnam has not been reported. METHODS AND PRINCIPAL FINDINGS: Face-to-face interviews including KAP survey were conducted in Bac Kan province, located in the northeast mountainous region of Vietnam. Participants were residents who lived in a community where H5N1 cases have ever been reported (event group, n = 322 or one where cases have not been reported (non-event group, n = 221. Data on emotional reactions of participants and healthcare-seeking behavior after the event in neighboring areas were collected as well as information on demographics and environmental measures, information sources, and KAP regarding H5N1. These data were compared between two groups. Higher environmental risk of H5N1 and improper poultry-handling behaviors were identified in the event group. At the time of the event, over 50% of the event group sought healthcare for flu-like symptoms or because they were scared. Awareness of the event influenced KAP scores. Healthcare-seeking behavior and attention to H5N1 poultry outbreaks diminished in the event group as time passed after the outbreak compared with the non-event group. Factors that motivated participants to seek healthcare sooner were knowledge of early access to healthcare and the risk of eating sick/dead poultry, and perception of the threat of H5N1. CONCLUSIONS: Awareness of H5N1 patients in neighboring areas can provoke panic in residents and influence their healthcare-seeking behavior. Periodic education to share experiences on the occurrence of H5N1 patients and provide accurate information may help prevent panic and infection and reduce mortality

  3. Risk Distribution of Human Infections with Avian Influenza H7N9 and H5N1 virus in China.

    Science.gov (United States)

    Li, Xin-Lou; Yang, Yang; Sun, Ye; Chen, Wan-Jun; Sun, Ruo-Xi; Liu, Kun; Ma, Mai-Juan; Liang, Song; Yao, Hong-Wu; Gray, Gregory C; Fang, Li-Qun; Cao, Wu-Chun

    2015-12-22

    It has been documented that the epidemiological characteristics of human infections with H7N9 differ significantly between H5N1. However, potential factors that may explain the different spatial distributions remain unexplored. We use boosted regression tree (BRT) models to explore the association of agro-ecological, environmental and meteorological variables with the occurrence of human cases of H7N9 and H5N1, and map the probabilities of occurrence of human cases. Live poultry markets, density of human, coverage of built-up land, relative humidity and precipitation were significant predictors for both. In addition, density of poultry, coverage of shrub and temperature played important roles for human H7N9 infection, whereas human H5N1 infection was associated with coverage of forest and water body. Based on the risks and distribution of ecological characteristics which may facilitate the circulation of the two viruses, we found Yangtze River Delta and Pearl River Delta, along with a few spots on the southeast coastline, to be the high risk areas for H7N9 and H5N1. Additional, H5N1 risk spots were identified in eastern Sichuan and southern Yunnan Provinces. Surveillance of the two viruses needs to be enhanced in these high risk areas to reduce the risk of future epidemics of avian influenza in China.

  4. 高致病性H5N1流感病毒所致人类感染

    Institute of Scientific and Technical Information of China (English)

    Andrea Gambotto; Simon M Barratt-Boyes; Menno D de Jong; Gabriele Neumann; Yoshihiro Kawaoka; 林磊(译); 秦成峰(译)

    2009-01-01

    自2003年以来,H5N1高致病性流感病毒在全球无情肆虐,引起家禽大面积死亡,给养殖业主造成了巨大损失。至今已报告的人感染H5N1流感病例达300多例,病死率高达60%。由于H5N1流感病毒具有高致病性,并且可由禽类传染至人,人们担心会出现一场新的人类流感大流行,就像1918年在西班牙发生的著名的H1N1型大流感一样。鉴于H5N1流感在多方面的研究进展都很迅速,本专题中,我们将着重讨论临床医生和研究人员所感兴趣的课题的最新进展。这里,我们将总结人类感染H5N1流感病毒的临床症状、

  5. The first specific detection of a highly pathogenic avian influenza virus (H5N1) in Ivory Coast.

    Science.gov (United States)

    Couacy-Hymann, E; Danho, T; Keita, D; Bodjo, S C; Kouakou, C; Koffi, Y M; Beudje, F; Tripodi, A; de Benedictis, P; Cattoli, G

    2009-02-01

    The Virology Laboratory of the Central Laboratory of Animal Diseases in Ivory Coast at Bingerville received samples of wild and domestic avian species between February and December 2006. An RT-PCR technique was used to test for avian influenza (AI) and highly pathogenic AI subtype viruses. Among 2125 samples, 16 were type A positive; of which, 12 were later confirmed to be H5N1. Fifteen of these 16 type A positive samples were inoculated into the chorioallantoic cavity of 11-day-old embryonated hens' eggs for virus isolation. Eight produced virus with hemagglutination titres from 1/64 to 1/512. The 4/16 M-RT-PCR positive samples, which were H5N1 negative, were shown to be H7 subtype negative. The diagnostic efficiency of the laboratory for the surveillance of H5N1 in Ivory Coast was demonstrated. The positive cases of H5N1 were from a sparrowhawk (Accipter nisus); live market poultry and in free-range poultry, where the mortality rate was approximately 20% (2/10) and 96.7% (29/30) respectively. Currently, investigations into intensive poultry farms have proved negative for H5N1. No human cases have been reported this time.

  6. Ecology and geography of avian influenza (HPAI H5N1 transmission in the Middle East and northeastern Africa

    Directory of Open Access Journals (Sweden)

    Peterson A Townsend

    2009-07-01

    Full Text Available Abstract Background The emerging highly pathogenic avian influenza strain H5N1 ("HPAI-H5N1" has spread broadly in the past decade, and is now the focus of considerable concern. We tested the hypothesis that spatial distributions of HPAI-H5N1 cases are related consistently and predictably to coarse-scale environmental features in the Middle East and northeastern Africa. We used ecological niche models to relate virus occurrences to 8 km resolution digital data layers summarizing parameters of monthly surface reflectance and landform. Predictive challenges included a variety of spatial stratification schemes in which models were challenged to predict case distributions in broadly unsampled areas. Results In almost all tests, HPAI-H5N1 cases were indeed occurring under predictable sets of environmental conditions, generally predicted absent from areas with low NDVI values and minimal seasonal variation, and present in areas with a broad range of and appreciable seasonal variation in NDVI values. Although we documented significant predictive ability of our models, even between our study region and West Africa, case occurrences in the Arabian Peninsula appear to follow a distinct environmental regime. Conclusion Overall, we documented a variable environmental "fingerprint" for areas suitable for HPAI-H5N1 transmission.

  7. Multiplexed, rapid detection of H5N1 using a PCR-free nanoparticle-based genomic microarray assay

    Directory of Open Access Journals (Sweden)

    Ragupathy Viswanath

    2010-10-01

    Full Text Available Abstract Background For more than a decade there has been increasing interest in the use of nanotechnology and microarray platforms for diagnostic applications. In this report, we describe a rapid and simple gold nanoparticle (NP-based genomic microarray assay for specific identification of avian influenza virus H5N1 and its discrimination from other major influenza A virus strains (H1N1, H3N2. Results Capture and intermediate oligonucleotides were designed based on the consensus sequences of the matrix (M gene of H1N1, H3N2 and H5N1 viruses, and sequences specific for the hemaglutinin (HA and neuraminidase (NA genes of the H5N1 virus. Viral RNA was detected within 2.5 hours using capture-target-intermediate oligonucleotide hybridization and gold NP-mediated silver staining in the absence of RNA fragmentation, target amplification, and enzymatic reactions. The lower limit of detection (LOD of the assay was less than 100 fM for purified PCR fragments and 103 TCID50 units for H5N1 viral RNA. Conclusions The NP-based microarray assay was able to detect and distinguish H5N1 sequences from those of major influenza A viruses (H1N1, H3N2. The new method described here may be useful for simultaneous detection and subtyping of major influenza A viruses.

  8. PB2 Segment Promotes High-pathogenicity Of H5N1 Avian Influenza Viruses In Mice

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    Hailiang eSun

    2015-02-01

    Full Text Available H5N1 influenza viruses with high lethality are a continuing threat to humans and poultry. Recently, H5N1 high-pathogenicity avian influenza virus (HPAIV has been shown to transmit through aerosols between ferrets in lab experiments by acquiring some mutation. This is another deeply aggravated threat of H5N1 HPAIV to humans. To further explore the molecular determinant of H5N1 HPAIV virulence in a mammalian model, we compared the virulence of A/Duck/Guangdong/212/2004 (DK212 and A/Quail/Guangdong/90/2004 (QL90. Though they were genetically similar, they had different pathogenicity in mice, as well as their 16 reassortants. The results indicated that a swap of the PB2 gene could dramatically decrease the virulence of rgDK212 in mice (1896-fold but increase the virulence of rgQL90 in mice (60-fold. Furthermore, the polymerase activity assays showed that swapping PB2 genes between these two viruses significantly changed the activity of polymerase complexes in 293T cells. The mutation Ser715Asn in PB2 sharply attenuated the virulence of rgDK212 in mice (2710-fold. PB2 segment promotes high-pathogenicity of H5N1 avian influenza viruses in mice and 715 Ser in PB2 plays an important role in determing high virulence of DK212 in mice.

  9. Changes in poultry handling behavior and poultry mortality reporting among rural Cambodians in areas affected by HPAI/H5N1.

    Directory of Open Access Journals (Sweden)

    Maria D Van Kerkhove

    Full Text Available BACKGROUND: Since 2004, 21 highly pathogenic avian influenza H5N1 outbreaks in domestic poultry and eight human cases have been confirmed in Cambodia. As a result, a large number of avian influenza education campaigns have been ongoing in provinces in which H5N1outbreaks have occurred in humans and/or domestic poultry. METHODOLOGY/PRINCIPAL FINDINGS: Data were collected from 1,252 adults >15 years old living in two southern provinces in Cambodia where H5N1 has been confirmed in domestic poultry and human populations using two cross-sectional surveys conducted in January 2006 and in November/December 2007. Poultry handling behaviors, poultry mortality occurrence and self-reported notification of suspect H5N1 poultry cases to animal health officials in these two surveys were evaluated. Our results demonstrate that although some at risk practices have declined since the first study, risky contact with poultry is still frequent. Improved rates of reporting poultry mortality were observed overall, but reporting to trained village animal health workers decreased by approximately 50%. CONCLUSIONS/SIGNIFICANCE: Although some improvements in human behavior have occurred, there are still areas--particularly with respect to the handling of poultry among children and the proper treatment of poultry and the surrounding household environment--that need to be addressed in public health campaigns. Though there were some differences in the sampling methods of the 2006 and 2007 surveys, our results illustrate the potential to induce considerable, potentially very relevant, behavioral changes over a short period of time.

  10. The evolutionary dynamics of highly pathogenic avian influenza H5N1 in south-central Vietnam reveals multiple clades evolving from Chinese and Cambodian viruses.

    Science.gov (United States)

    Nguyen, Tinh Huu; Than, Van Thai; Thanh, Hien Dang; Nguyen, Van Quang; Nguyen, Kim Hue; Nguyen, Duc Tan; Park, Jong-Hwa; Chung, In Sik; Jeong, Dae Gwin; Chang, Kyu-Tae; Oh, Tae Kwang; Kim, Wonyong

    2015-10-01

    In Vietnam, highly pathogenic avian influenza (HPAI), such as that caused by H5N1 viruses, is the most highly contagious infectious disease that has been affecting domestic poultry in recent years. Vietnam might be an evolutionary hotspot and a potential source of globally pandemic strains. However, few studies have reported viruses circulating in the south-central region of Vietnam. In the present study, 47 H5N1-positive samples were collected from both vaccinated and unvaccinated poultry farms in the South Central Coast region of Vietnam during 2013-2014, and their genetic diversity was analyzed. A common sequence motif for HPAI virus was identified at HA-cleavage sites in all samples: either RERRRKR/G (clades 2.3.2.1c and 2.3.2.1a) or REGRRKKR/G (clade 1.1.2). Phylogenetic analysis of HA genes identified three clades of HPAI H5N1: 1.1.2 (n=1), 2.3.2.1a (n=1), and 2.3.2.1c (n=45). The phylogenetic analysis indicated that these Vietnamese clades may have evolved from Chinese and Cambodian virus clades isolated in 2012-2013 but are less closely related to the clades detected from the Tyva Republic, Bulgaria, Mongolia, Japan, and Korea in 2009-2011. Detection of the coexistence of virus clades 2.3.2.1 and the very virulent 1.1.2 in the south-central regions suggests their local importance and highlights concerns regarding their spread, both northwards and southwards, as well as the potential for reassortment. The obtained data highlight the importance of regular identification of viral evolution and the development and use of region-specific vaccines.

  11. Global alert to avian influenza virus infection: from H5N1 to H7N9.

    Science.gov (United States)

    Poovorawan, Yong; Pyungporn, Sunchai; Prachayangprecha, Slinporn; Makkoch, Jarika

    2013-07-01

    Outbreak of a novel influenza virus is usually triggered by mutational change due to the process known as 'antigenic shift' or re-assortment process that allows animal-to-human or avian-to-human transmission. Birds are a natural reservoir for the influenza virus, and subtypes H5, H7, and H9 have all caused outbreaks of avian influenza in human populations. An especially notorious strain is the HPAI influenza virus H5N1, which has a mortality rate of approximately 60% and which has resulted in numerous hospitalizations, deaths, and significant economic loss. In March 2013, in Eastern China, there was an outbreak of the novel H7N9 influenza virus, which although less pathogenic in avian species, resulted in 131 confirmed cases and 36 deaths in humans over a two-month span. The rapid outbreak of this virus caused global concern but resulted in international cooperation to control the outbreak. Furthermore, cooperation led to valuable research-sharing including genome sequencing of the virus, the development of rapid and specific diagnosis, specimen sharing for future studies, and vaccine development. Although a H7N9 pandemic in the human population is possible due to its rapid transmissibility and extensive surveillance, the closure of the live-bird market will help mitigate the possibility of another H7N9 outbreak. In addition, further research into the source of the outbreak, pathogenicity of the virus, and the development of specific and sensitive detection assays will be essential for controlling and preparing for future H7N9 outbreaks.

  12. Stepwise prediction and statistical screening: B-cell epitopes on neuraminidase of human avian H5N1 virus

    Institute of Scientific and Technical Information of China (English)

    HUANG Ping; YU ShouYi; KE ChangWen

    2008-01-01

    The B-cell epitopes of virus are associated with the antiviral drug and the vaccine screening. As the nucleotide sequences of neuraminidase (NA) of stain GD-01-06 were sequenced, we predicted the α-helix and β-fold structure and the indexes of the flexible regions of secondary structure of NA with methods of the Hydrophilicity plot by Kyte-Doolittle, the Surface probability plot by Emini and the Antigenic index by Jameson-Wolf, and then screened statistically the parameters to predict B-cell epitopes by the Hierarchical cluster and the Bivariate correlation and the quartiles with SPSS 13.0. The impact of variation of amino acids in NA on its epitopes was analyzed. The predictive results were evaluated by Wu's Antigenic Index and SWISS-MODEL. We found that the most possible epitopes on NA were located within or nearby its N-terminal Nos. 120-137, 81 -84, 408-415, 273-282, 429-432,356-368, 46-55,146-155, 341-350 and 198-209, which were the dominant regions of NA epitopes.Peptide 120-137 including the glycoprotein domain (NGT(126-128)) was first chosen as the B-cell epitopes on NA. NA in H5N1 strain isolated after 2003 lacked in No. 53 amino acid (I), resulting in an increase in the surface flexible region of NA in GD-01-06 and an enlargement to their epitope regions (VEP(46-48→VEPISNTNFL(46-55)). Conclusively, prediction of the B-cell epitopes on the NA based on multiple parameters is useful for researches on the molecular immunology and drug screening and immuno-prophylaxis. A deletion of No. 53 amino acid (I) in NA in strain GD-01-06 might increase its antigenicity.

  13. H5N1型禽流感病毒广谱中和单克隆抗体的筛选及其中和机制初步研究%Broad-spectrum Neutralizing Monoclonal Antibodies Against H5N1 Avian Influenza A Viruses and Primary Research on The Mechanism

    Institute of Scientific and Technical Information of China (English)

    张晓; 曾晓燕; 刘哲; 金秋; 徐言; 冯振卿; 焦永军

    2011-01-01

    counter the H5N1 influenza A virus, and the epitope could be the key point for the design and implementation of vaccines.%利用杆状病毒-昆虫细胞表达H5N1型禽流感病毒的血凝素蛋白(HA),纯化后的重组蛋白HA免疫小鼠并制备杂交瘤单克隆抗体,用H5N1型禽流感病毒的全病毒进行筛选,成功地获得了抗H5N1型禽流感病毒血凝素蛋白HA的单抗.MDCK细胞微量中和试验表明,单抗8G10D7可对clade2和clade9的H5N1型禽流感病毒起中和作用.Western-blot及血凝抑制实验进一步证明了该单抗的结合位点位于HA蛋白的HA1亚基上.鸡胚感染病毒预防试验结果表明,8G10D7对禽来源的和人来源的H5N1型禽流感病毒均可达到100%的保护率;在治疗试验组中,8G10D7对禽来源的病毒感染具有较高的保护率,可达100%,对人来源的H5N1型禽流感病毒最高也可达87.5%的保护率.该抗体的获得不仅为H5N1型高致病性禽流感病毒的预防和治疗带来了希望,同时其中和位点的发现也为以后亚单位疫苗的研制提供新的思路.

  14. Molecular evolution of H5N1 highly pathogenic avian influenza viruses in Bangladesh between 2007 and 2012.

    Science.gov (United States)

    Haque, M E; Giasuddin, M; Chowdhury, E H; Islam, M R

    2014-01-01

    In Bangladesh, highly pathogenic avian influenza (HPAI) virus subtype H5N1 was first detected in February 2007. Since then the virus has become entrenched in poultry farms of Bangladesh. There have so far been seven human cases of H5N1 HPAI infection in Bangladesh with one death. The objective of the present study was to investigate the molecular evolution of H5N1 HPAI viruses during 2007 to 2012. Partial or complete nucleotide sequences of all eight gene segments of two chicken isolates, five gene segments of a duck isolate and the haemagglutinin gene segment of 18 isolates from Bangladesh were established in the present study and subjected to molecular analysis. In addition, full-length sequences of different gene segments of other Bangladeshi H5N1 isolates available in GenBank were included in the analysis. The analysis revealed that the first introduction of clade 2.2 virus in Bangladesh in 2007 was followed by the introduction of clade 2.3.2.1 and 2.3.4 viruses in 2011. However, only clade 2.3.2.1 viruses could be isolated in 2012, indicating progressive replacement of clade 2.2 and 2.3.4 viruses. There has been an event of segment re-assortment between H5N1 and H9N2 viruses in Bangladesh, where H5N1 virus acquired the PB1 gene from a H9N2 virus. Point mutations have accumulated in Bangladeshi isolates over the last 5 years with potential modification of receptor binding site and antigenic sites. Extensive and continuous molecular epidemiological studies are necessary to monitor the evolution of circulating avian influenza viruses in Bangladesh.

  15. PHYLOGENETIC AND ANTIGENIC STRUCTURE OF AVIAN INFLUENZA VIRUS OF H5N1 SUBTYPE ISOLATED FROM WATERFOWLS

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    R Susanti

    2008-09-01

    Full Text Available A study was carried (1 to analyze the phylogenetic relationship of fragment hemaglutinin (HA geneof avian influenza viruses (AIV subtype H5N1 isolated from apparently healthy backyard waterfowls inWest Java with representative of animal and human isolates from Indonesia and some countries in Asia;(2 to find out cross-reactivity of those viruses with a standard Indonesian strain. Nucleotide sequences ofHA gene of AIV H5N1 from backyard waterfowls along with other H5N1 isolates of Indonesian and Asianorigin were aligned using with ClustalW of MEGA 3.1 program. Estimation of genetic distance and theconstruction phylogenetic tree were conducted by Neighbor Joining method and calculation of distancematrix using Kimura 2-parameter. Antigenic analysis was conducted using hemagglutination inhibition(HI test. Result of phylogenetic analysis indicated that all viruses from backyard waterfowls form threedistinct sublineages. One lineage was located in Indonesia cluster and two lineages in Asia cluster. In thephylogenetic analysis, it was concluded that multiple introductions of AIV H5N1 to Indonesia have occurred.Six AI H5N1 viruses from backyard waterfowls (IPB1-RS to IPB6-RS appeared to be different ancestorsthose isolated previously in Indonesia. Cross-antigenic analysis showed that nine viruses isolates used inthis study were antigenically different to Legok 2003 chicken strain of AIV H5N1. The HI titer of anti-Legok 2003 antibody with all newly isolated viruses is up to 6 log lower then the HI titer using homologstrain.

  16. Expression of hemagglutinin protein from the avian influenza virus H5N1 in a baculovirus/insect cell system significantly enhanced by suspension culture

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    Spencer Lynn

    2006-02-01

    Full Text Available Abstract Background Prevention of a possible avian influenza pandemic necessitates the development of rapid diagnostic tests and the eventual production of a vaccine. Results For vaccine production, hemagglutinin (HA1 from avian influenza H5N1 was expressed from a recombinant baculovirus. Recombinant HA1 was expressed in monolayer or suspension culture insect cells by infection with the recombinant baculovirus. The yield of rHA1 from the suspension culture was 68 mg/l, compared to 6 mg/l from the monolayer culture. Immunization of guinea pigs with 50 μg of rHA1 yielded hemagglutinin inhibition and virus neutralization titers of 1:160 after two times vaccination with rHA1 protein. Conclusion Thus, the production of rHA1 using an insect suspension cell system provides a promising basis for economical production of a H5 antigen.

  17. Observations from a live bird market in Indonesia following a contained outbreak of avian influenza A (H5N1).

    Science.gov (United States)

    Naysmith, Scott

    2014-01-01

    Live bird markets are considered high-risk environments facilitating viral transfer and replication of influenza A H5N1. In Indonesia, these markets have been the source for multiple human infections of H5N1 resulting in death, and thus have been the focus of government-led interventions. This paper examines the aftermath of an intervention in one market in Bali, Indonesia. It highlights the social and economic factors influencing the adoption of risk prevention behaviour and concludes by arguing for further qualitative research to understand why at-risk individuals fail to adopt biosecurity measures, even after recently experiencing an outbreak of avian influenza.

  18. The Mx1 Gene Protects Mice against the Pandemic 1918 and Highly Lethal Human H5N1 Influenza Viruses▿

    OpenAIRE

    2007-01-01

    Mice carrying a wild-type Mx1 gene (Mx1+/+) differ from standard laboratory mice (Mx1−/−) in being highly resistant to infection with common laboratory strains of influenza A virus. We report that Mx1 also protects mice against the pandemic human 1918 influenza virus and a highly lethal human H5N1 strain from Vietnam. Resistance to H5N1 of Mx1+/+ but not Mx1−/− mice was enhanced if the animals were treated with a single dose of exogenous alpha interferon before infection. Thus, the interferon...

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

    Directory of Open Access Journals (Sweden)

    Margaret A Carrel

    Full Text Available 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 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. METHODOLOGY/PRINCIPAL FINDINGS: 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. CONCLUSIONS/SIGNIFICANCE: 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

  20. Improving global influenza surveillance: trends of A(H5N1 virus in Africa and Asia

    Directory of Open Access Journals (Sweden)

    Escorcia Magdalena

    2012-01-01

    Full Text Available Abstract Background Highly pathogenic avian influenza A(H5N1 viruses are an important health problem in many Asian and African countries. The current increase in human cases demonstrates that influenza A(H5N1 is still a significant global pandemic threat. Many health organizations have recognized the need for new strategies to improve influenza global surveillance. Specifically, the World Health Organization through the global technical consultation for influenza surveillance have called for a detailed picture of the current limitations, especially at the nation level, to evaluate, standardize and strength reporting systems. The main goal of our study is to demonstrate the value of genetic surveillance as part of a strategic surveillance plan. As a proof of concept, we evaluated the current situation of influenza A(H5N1 in Asian and Africa. Results Our analysis revealed a power-law distribution in the number of sequences of A(H5N1 viruses analyzed and/or reported to influenza surveillance networks. The majority of the Asian and African countries at great risk of A(H5N1 infections have very few (approximately three orders of magnitude sequenced A(H5N1 viruses (e.g. hemagglutinin genes. This suggests that countries under pandemic alert for avian influenza A(H5N1 have very limited participation (e.g. data generation, genetic analysis and data share in avian influenza A(H5N1 surveillance. More important, this study demonstrates the usefulness of influenza genetic surveillance to detect emerging pandemic threat viruses. Conclusions Our study reveals that some countries suffering from human cases of avian influenza have limited participation (e.g. genetic surveillance or data share with global surveillance networks. Also, we demonstrate that the implementation of genetic surveillance programs could increase and strengthen worldwide epidemic and pandemic preparedness. We hope that this work promotes new discussions between policy makers and health

  1. 04068 Akzo Nobel正在研发H5N1禽流感疫苗

    Institute of Scientific and Technical Information of China (English)

    罗娟(摘)

    2006-01-01

    Akzo Nobel公司正在研发人用H5N1禽流感疫苗,现在研发处于初级阶段,由Akzo Nobel公司生物技术部Nobilon负责,制药部门Organon协助进行。公司预期2006年进行H5N1禽流感疫苗的临床试验。Akzo Nobel公司的动物保健科intervet提供了用于给鸟类接种的禽流感疫苗。

  2. 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.

  3. Research on Multiplication of H5N1 Subtype Avian Influenza Virus in MDCK Cell Culture System%H5N1亚型禽流感病毒在MDCK细胞中增殖条件的研究

    Institute of Scientific and Technical Information of China (English)

    孙德君; 梁婉楠; 丁国杰; 刘鑫莹; 袁明霞; 闫妍

    2014-01-01

    目的:探索H5N1亚型禽流感病毒在MDCK中增殖规律,确定最佳增殖条件。方法将H5N1亚型禽流感病毒接种到6孔板培养的MDCK细胞进行增殖试验,检测不同病毒感染量、不同浓度TPCK-胰酶,接毒后不同时间病毒的HA滴度。根据确定的最佳增殖条件将病毒接种到微载体培养的MDCK细胞中进行大规模增殖。结果:最佳病毒增殖条件接毒量MOI为5×10-4、TPCK-胰酶浓度为4μg/mL,在5 L生物反应器中重复验证,获得稳定的试验结果,病毒血凝价最高为8 log2。结论:本研究为禽流感疫苗的生物反应器规模化生产奠定了基础。%To explore the regularity for the multiplication of avian influenza virus subtype H5N1 in MDCK cell culture system and determine the optimal proliferation conditions. H5N1 subtype of avian influenza virus was in-oculated into the MDCK cell growing on 6 well plate, and the HA titers of virus at different time were detected in the conditions of different infectious doses, and different concentrations of TPCK-trypsin. The optimal conditions were determined. Then the H5N1 subtype avian influenza virus was grown in microcarrier-based MDCK cell. It was demonstrated that high virus yield with a hemagglutination unit of 8 log2 (1:256) could be obtained under the optimal conditions of multiplication. The result indicated the H5N1 subtype avian influenza virus could be pro-duced in microcarrier-based MDCK cell in a large-scale culture system with a high virus yield and demonstrates the feasibility of the development of mammalian cell-based in influenza vaccine in microcarrier culture systems.

  4. Pathogenesis of the 1918 pandemic and H5N1 influenza virus infection in a guinea pig model: The antiviral potential of exogenous alpha-interferon to reduce virus shedding

    Science.gov (United States)

    Although highly pathogenic avian influenza H5N1 viruses have yet to acquire the ability to transmit efficiently among humans, the geographic expansion, and continued outbreaks in humans and avian species underscore the need for more effective influenza vaccines and antivirals. Additional small anim...

  5. Detection of Markers of Increased Virulence Non Structural protein (NS I Avian Influenza Virus H5N1 from Indonesia=DETEKSI PENANDA PENINGKATAN VIRULENSI NON STRUKTURAL PROTEIN (NS1 VIRUS AVIAN INFLUENZA H5N1 ASAL INDONESIA

    Directory of Open Access Journals (Sweden)

    Arief Mulyono

    2015-03-01

    Full Text Available ENGLISHAbstractNS1 protein is a multifunction protein that plays key role of pathogenesis and virulence of avians influenza virus H5N1. The amino acid substitution at the position P42S, D92E, F103I, M106I and 5 amino acid deletion at the position 80 to 84 in NS1 protein reported increasing virulence of avians influenza virus H5N1. Several studies showed avians influenza virus H5N1 in Indonesia has dynamic changed. This study aimed to analyze the markers of virulence of NS1 protein sequences of all H5N1 virus isolates from Indonesia. The source of NS1 protein sequence data gene obtained from GeneBank and Gisaid. Data were analyzed using Bioedit software. The Results showed the isolates from Indonesia had substitutions P42S and 5 amino acids deletions at positions 80-84 resulting in the potential for increased virulence of the virus. However, amino acid substitution at the position D92E, F103L and M106I substitution were not found.INDONESIANAbstrakProtein NS1 adalah protein multifungsi yang memainkan peran kunci dalam patogenesis dan virulensi virus avian influenza H5N1. Substitusi asam amino P42S, D92E, F103I, M106I, dan delesi 5 asam amino di posisi 80 - 84 dilaporkan meningkatkan virulensi virus avian influenza H5N1. Beberapa penelitian menunjukkan bahwa virus avian influenza di Indonesia mengalami perubahan dinamis. Studi ini akan menganalisis motif asam amino yang menjadi penanda peningkatan virulensi pada sekuen protein NS1 virus avian influenza H5N1 asal Indonesia. Data sekuen asam amino protein NS1 diperoleh dari database GeneBank dan Gisaid. Analisis data menggunakan Bioedit software. Hasil analisis menunjukkan subtitusi asam amino dari prolin ke serin di posisi 42 (P42S dan delesi 5 asam amino di posisi 80 – 84 telah ditemukan pada virus avian influenza asal Indonesia, akan tetapi tidak ditemukan substitusi asam amino aspartat ke glutamat diposisi no 92 (D92E dan tidak ada yang mengalami 2 substitusi asam amino sekaligus diposisi 103

  6. Genetic dynamic analysis of the H5N1 Avian influenza virus NS1 gene isolated in Bali

    Directory of Open Access Journals (Sweden)

    Arief Mulyono

    2013-05-01

    Full Text Available AbstrakLatar belakang:Virus Avian Influenza H5N1 diperkirakan terus bermutasi, yang berpotensi meningkatkan kapasitas untuk melompati barier spesies, dan dapat menular secara mudah antar manusia. Penelitian ini bertujuan untuk menganalisis dinamika genetik gen NS1 dan mengetahui adanya marka virulensi pada sekuen gen NS1 VAI H5N1 ayam asal Bali.Metode: Metode yang digunakan dalam penelitian ini adalah isolasi RNA, amplifikasi gen NS1 dengan Reverse Transcriptase Polymerase Chain Reaction (RT-PCR, elektroforesis dan sequencing. Data sekuen isolat virus Avian influenza H5N1 asal Bali tersebut selanjutnya dibandingkan dengan multiple aligment dengan isolat asal Indonesia lainnya dari berbagai hospes yang diakses melalui GenBank tahun 2005-2007, dan pembuatan pohon filogenetik.Hasil:Keempat isolat uji mengalami substitusi P42S dan delesi 5 asam amino pada posisi 80-84 yang mengakibatkan potensi peningkatan virulensi virus, namun tidak dijumpai adanya substitusi D92E, F103L dan M106I. Analisis filogenetik menunjukkan keempat isolat uji mempunyai kekerabatan genetik lebih dekat dengan isolat asal kucing dan manusia. Dibandingkan dengan isolat Bali tahun 2005 isolat uji mengalami peningkatan substitusi nukleotida dan asam amino.Kesimpulan:Isolat VAI H5N1 asal Bali mengalami dinamika genetik dan ditemukan marker virulensi pada sekuen gen NS1. (Health Science Indones 2012;2:xx-xxKata kunci: avian influenza, H5N1, NS1Abstract Background:H5N1 Avian Influenza virus is expected to continue to mutate, potentially increasing the capacity to jump the species barrier, and can be easily transmitted between humans. This study aimed to analyze the genetic dynamics of the NS1 gene and to recognize markers of virulence in VAI H5N1 NS1 gene sequences from Balinese poultry.Methods:The method used was isolation of RNA, NS1 gene amplification  by  Reverse  Transcriptase Polymerase Chain Reaction (RT-PCR, electrophoresis and sequencing. Data sequence Avian influenza H5

  7. 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 routes

  8. 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,

  9. 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.

  10. 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 t

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

    Science.gov (United States)

    Chen, Li-Mei; Blixt, Ola; Stevens, James; Lipatov, Aleksandr S; Davis, Charles T; Collins, Brian E; Cox, Nancy J; Paulson, James C; Donis, Ruben O

    2012-01-05

    Acquisition of α2-6 sialoside receptor specificity by α2-3 specific highly-pathogenic avian influenza viruses (H5N1) is thought to be a prerequisite for efficient transmission in humans. By in vitro selection for binding α2-6 sialosides, we identified four variant viruses with amino acid substitutions in the hemagglutinin (S227N, D187G, E190G, and Q196R) that revealed modestly increased α2-6 and minimally decreased α2-3 binding by glycan array analysis. However, a mutant virus combining Q196R with mutations from previous pandemic viruses (Q226L and G228S) revealed predominantly α2-6 binding. 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.

  12. 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...

  13. Construction of a Chimeric Secretory IgA and Its Neutralization Activity against Avian Influenza Virus H5N1

    Directory of Open Access Journals (Sweden)

    Cun Li

    2014-01-01

    Full Text Available Secretory immunoglobulin A (SIgA acts as the first line of defense against respiratory pathogens. In this assay, the variable regions of heavy chain (VH and Light chain (VL genes from a mouse monoclonal antibody against H5N1 were cloned and fused with human IgA constant regions. The full-length chimeric light and heavy chains were inserted into a eukaryotic expressing vector and then transfected into CHO/dhfr-cells. The chimeric monomeric IgA antibody expression was confirmed by using ELISA, SDS-PAGE, and Western blot. In order to obtain a dimeric secretory IgA, another two expressing plasmids, namely, pcDNA4/His A-IgJ and pcDNA4/His A-SC, were cotransfected into the CHO/dhfr-cells. The expression of dimeric SIgA was confirmed by using ELISA assay and native gel electrophoresis. In microneutralization assay on 96-well immunoplate, the chimeric SIgA showed neutralization activity against H5N1 virus on MDCK cells and the titer was determined to be 1 : 64. On preadministrating intranasally, the chimeric SIgA could prevent mice from lethal attack by using A/Vietnam/1194/04 H5N1 with a survival rate of 80%. So we concluded that the constructed recombinant chimeric SIgA has a neutralization capability targeting avian influenza virus H5N1 infection in vitro and in vivo.

  14. Risk factors for highly pathogenic avian influenza (HPAI) H5N1 infection in backyard chicken farms, Thailand.

    Science.gov (United States)

    Paul, Mathilde; Wongnarkpet, Sirichai; Gasqui, Patrick; Poolkhet, Chaithep; Thongratsakul, Sukanya; Ducrot, Christian; Roger, François

    2011-06-01

    To reduce the risk of highly pathogenic avian influenza (HPAI) H5N1 infection in humans, the pathways by which HPAI is spread in poultry must be determined. Backyard poultry farmers are particularly vulnerable to the threat of HPAI, with both their health and livelihoods at risk. Identifying the risk factors for HPAI infection in backyard farms should allow control measures to be better targeted. To study the risk factors of HPAI H5N1 infection, we carried out a case-control study on backyard chicken farms in Thailand, analyzing 104 case farms and 382 control farms. Data on farming practices and environmental characteristics were analyzed using multivariate logistic regression models. We show that farms where owners bought live chickens from another backyard farm had a higher risk of HPAI H5N1 infection (OR 3.34, 95% CI 1.72-6.47), while those where owners used a disinfectant to clean poultry areas were exposed to lower risk (OR 0.48, 95% CI 0.26-0.87). Our results highlight the important role of the trade of poultry between farms in the transmission of HPAI H5N1, in addition to farming practices and environmental characteristics. Findings from this study may help to tailor prevention measures to the local circumstances of backyard farms in different regions of the world.

  15. Human influenza A H5N1 in Indonesia: health care service-associated delays in treatment initiation.

    Science.gov (United States)

    Adisasmito, Wiku; Aisyah, Dewi Nur; Aditama, Tjandra Yoga; Kusriastuti, Rita; Trihono; Suwandono, Agus; Sampurno, Ondri Dwi; Prasenohadi; Sapada, Nurshanty A; Mamahit, M J N; Swenson, Anna; Dreyer, Nancy A; Coker, Richard

    2013-06-11

    Indonesia has had more recorded human cases of influenza A H5N1 than any other country, with one of the world's highest case fatality rates. Understanding barriers to treatment may help ensure life-saving influenza-specific treatment is provided early enough to meaningfully improve clinical outcomes. Data for this observational study of humans infected with influenza A H5N1 were obtained primarily from Ministry of Health, Provincial and District Health Office clinical records. Data included time from symptom onset to presentation for medical care, source of medical care provided, influenza virology, time to initiation of influenza-specific treatment with antiviral drugs, and survival. Data on 124 human cases of virologically confirmed avian influenza were collected between September 2005 and December 2010, representing 73% of all reported Indonesia cases. The median time from health service presentation to antiviral drug initiation was 7.0 days. Time to viral testing was highly correlated with starting antiviral treatment (p influenza H5N1 in Indonesia appear related to delays in diagnosis rather than presentation to health care settings. Either cases are not suspected of being H5N1 cases until nearly one week after presenting for medical care, or viral testing and/or antiviral treatment is not available where patients are presenting for care. Health system delays have increased since 2007.

  16. Asymptomatic infection with highly pathogenic avian influenza H5N1 in wild birds: how sound is the evidence?

    Directory of Open Access Journals (Sweden)

    Yasué Maï

    2006-11-01

    Full Text Available Abstract Background Widespread deaths of wild birds from which highly pathogenic avian influenza virus H5N1 has been isolated suggest that the virus continues to be lethal to them. However, asymptomatic carriage by some wild birds could allow birds to spread the virus on migration. Confirmation of such carriage is therefore important for the design of mitigation measures for the disease in poultry. Discussion Two recent papers have reported the isolation of H5N1 from a small number of water birds in China and Russia and have concluded that wild birds can spread the viruses over long distances on migration. However, both papers contain weaknesses in the provision of ornithological and associated data that compromise conclusions that can be reached about the role of wild birds in the spread of H5N1. We describe the weaknesses of these studies and highlight the need for improved methodological description and methodology, where appropriate, and further research. Summary A rigorous assessment of whether wild birds can carry H5N1 asymptomatically is critical to evaluating the risks of spread by migratory birds on long-distance migration.

  17. 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. How

  18. Molecular characterization of highly pathogenic H5N1 avian influenza A viruses isolated from raccoon dogs in China.

    Directory of Open Access Journals (Sweden)

    Xian Qi

    Full Text Available BACKGROUND: The highly pathogenic avian influenza H5N1 virus can infect a variety of animals and continually poses a threat to animal and human health. While many genotypes of H5N1 virus can be found in chicken, few are associated with the infection of mammals. Characterization of the genotypes of viral strains in animal populations is important to understand the distribution of different viral strains in various hosts. This also facilitates the surveillance and detection of possible emergence of highly pathogenic strains of specific genotypes from unknown hosts or hosts that have not been previously reported to carry these genotypes. METHODOLOGY/PRINCIPAL FINDINGS: Two H5N1 isolates were obtained from lung samples of two raccoon dogs that had died from respiratory disease in China. Pathogenicity experiments showed that the isolates were highly pathogenic to chicken. To characterize the genotypes of these viruses, their genomic sequences were determined and analyzed. The genetic contents of these isolates are virtually identical and they may come from the same progenitor virus. Phylogenetic analysis indicated that the isolates were genetically closely related to genotype V H5N1 virus, which was first isolated in China in 2003, and were distinct from the dominant virus genotypes (e.g. genotype Z of recent years. The isolates also contain a multibasic amino acid motif at their HA cleavage sites and have an E residue at position 627 of the PB2 protein similar to the previously-identified avian viruses. CONCLUSIONS/SIGNIFICANCE: This is the first report that genotype V H5N1 virus is found to be associated with a mammalian host. Our results strongly suggest that genotype V H5N1 virus has the ability to cross species barriers to infect mammalian animals. These findings further highlight the risk that avian influenza H5N1 virus poses to mammals and humans, which may be infected by specific genotypes that are not known to infect these hosts.

  19. X-ray structure of NS1 from a highly pathogenic H5N1 influenza virus

    Energy Technology Data Exchange (ETDEWEB)

    Bornholdt, Zachary A.; Prasad, B.V. Venkataram (Baylor)

    2009-04-08

    The recent emergence of highly pathogenic avian (H5N1) influenza viruses, their epizootic and panzootic nature, and their association with lethal human infections have raised significant global health concerns. Several studies have underlined the importance of non-structural protein NS1 in the increased pathogenicity and virulence of these strains. NS1, which consists of two domains - a double-stranded RNA (dsRNA) binding domain and the effector domain, separated through a linker - is an antagonist of antiviral type-I interferon response in the host. Here we report the X-ray structure of the full-length NS1 from an H5N1 strain (A/Vietnam/1203/2004) that was associated with 60% of human deaths in an outbreak in Vietnam. Compared to the individually determined structures of the RNA binding domain and the effector domain from non-H5N1 strains, the RNA binding domain within H5N1 NS1 exhibits modest structural changes, while the H5N1 effector domain shows significant alteration, particularly in the dimeric interface. Although both domains in the full-length NS1 individually participate in dimeric interactions, an unexpected finding is that these interactions result in the formation of a chain of NS1 molecules instead of distinct dimeric units. Three such chains in the crystal interact with one another extensively to form a tubular organization of similar dimensions to that observed in the cryo-electron microscopy images of NS1 in the presence of dsRNA. The tubular oligomeric organization of NS1, in which residues implicated in dsRNA binding face a 20-{angstrom}-wide central tunnel, provides a plausible mechanism for how NS1 sequesters varying lengths of dsRNA, to counter cellular antiviral dsRNA response pathways, while simultaneously interacting with other cellular ligands during an infection.

  20. Cracking the code for H5N1-bird flu and beyond.

    Science.gov (United States)

    Thomson, Robin J; Haselhorst, Thomas; Dyason, Jeffrey C; von Itzstein, Mark

    2009-08-01

    Influenza virus remains a significant threat to humanity despite the discovery of novel anti-viral therapies and the continuing development of seasonal vaccines. The reason for this ongoing concern is that the development of drug resistance to anti-virals has rapidly occurred and the currently developed vaccines are typically only effective against a specific influenza virus strain. The continual emergence of new influenza virus strains that may lead to the next human pandemic has inspired much research into a better understanding of the virus, particularly the role(s) of carbohydrates in the virus' lifecycle. Much of this research is directed towards next generation anti-influenza drugs. Important advances in the interrogation of influenza virus' surface glycoprotein haemagglutinin by NMR spectroscopy have been made in recent times. An overview of some of these advances is provided.

  1. Avian Influenza-the Epidemiology of Human H5N1 Cases Reported to WHO%世卫组织人间禽流感H5N1病例流行病学分析

    Institute of Scientific and Technical Information of China (English)

    张燕

    2007-01-01

    世卫组织在线出版的本周《疫情周报》提出了从2003—12/2006—04—30按发病日期向世卫组织正式报告的所有205例实验室确诊的H5N1病例流行病学数据首次分析结果。

  2. Multiple reassortment events among highly pathogenic avian influenza A(H5N1) viruses detected in Bangladesh.

    Science.gov (United States)

    Gerloff, Nancy A; Khan, Salah Uddin; Balish, Amanda; Shanta, Ireen S; Simpson, Natosha; Berman, Lashondra; Haider, Najmul; Poh, Mee Kian; Islam, Ausraful; Gurley, Emily; Hasnat, Md Abdul; Dey, T; Shu, Bo; Emery, Shannon; Lindstrom, Stephen; Haque, Ainul; Klimov, Alexander; Villanueva, Julie; Rahman, Mahmudur; Azziz-Baumgartner, Eduardo; Ziaur Rahman, Md; Luby, Stephen P; Zeidner, Nord; Donis, Ruben O; Sturm-Ramirez, Katharine; Davis, C Todd

    2014-02-01

    In Bangladesh, little is known about the genomic composition and antigenicity of highly pathogenic avian influenza A(H5N1) viruses, their geographic distribution, temporal patterns, or gene flow within the avian host population. Forty highly pathogenic avian influenza A(H5N1) viruses isolated from humans and poultry in Bangladesh between 2008 and 2012 were analyzed by full genome sequencing and antigenic characterization. The analysis included viruses collected from avian hosts and environmental sampling in live bird markets, backyard poultry flocks, outbreak investigations in wild birds or poultry and from three human cases. Phylogenetic analysis indicated that the ancestors of these viruses reassorted (1) with other gene lineages of the same clade, (2) between different clades and (3) with low pathogenicity avian influenza A virus subtypes. Bayesian estimates of the time of most recent common ancestry, combined with geographic information, provided evidence of probable routes and timelines of virus spread into and out of Bangladesh.

  3. ISOLASI DAN IDENTIFIKASI VIRUS AVIAN INFLUENZA SUBTIPE H5N1 DI PETERNAKAN TRADISIONAL KECAMATAN GUNUNGPATI SEMARANG

    Directory of Open Access Journals (Sweden)

    Angga Ari Wibowo

    2012-09-01

    Full Text Available Avian Influenza (AI atau yang lebih dikenal dengan flu burung disebabkan oleh virus influenza yang bermutasi menjadi patogen. Penelitian tentang isolasi dan identifikasi virus AI subtipe H5N1 perlu dilakukan untuk mengetahui keberadaan virus tersebut khususnya di kecamatan Gunungpati. Desain penelitian adalah eks ploratif dengan pengumpulan sampel usap kloaka secara acak di lima kelurahan di kecamatan Gunungpati. Sampel usap kloaka ditumbuhkan pada telur ayam berembrio SPF, kemudian diisolasi RNA-nya dilanjutkan dengan identifikasi subtipe virus AI menggunakan Reverse Transcriptase-Polymerase Chain Reaction (RT–PCR dengan primer pendeteksi gen H5 dan N1. Hasil positif apabila visualisasi hasil elektroforesis dari produk PCR menunjukkan pita-pita spesifik panjang 219 bp untuk H5 dan 131 bp untuk gen N1-nya. Limapuluh sampel usap kloaka yang diisolasi dari lima kelurahan di Gunungpati, delapan isolat positif VAI dan enam diantaranya positif H5N1 dengan angka prevalensi 12%. Isolat positif berasal dari 2 spesies itik (16,67%, 2 dari entok (11,76% dan 2 dari angsa (18,18%. Dari lima kelurahan yang diambil sampelnya, tiga kelurahan ditemukan positif virus H5N1 masing-masing kelurahan Sekaran (6,67%, Kalisegoro (16,67% dan Pakintelan (15,78%. Unggas-unggas air di peternakan unggas tradisional berpotensi sebagai penularan virus AI, khususnya subtipe H5N1.Avian Influenza (AI or better known as bird flu is caused by influenza viruses that mutate into a pathogen. Research on the isolation and the identification of H5N1 subtype needed to be carried out to determine the presence of the virus, particularly in the subdistrict of Gunungpati. The study design was explorative by collecting cloacal swab samples randomly from five villages in Gunungpati. The cloacal swab samples were cultured in embryonated SPF chicken eggs, then the RNA was isolated and followed by the identification of AI virus subtype using Reverse Transcriptase-Polymerase Chain Reaction (RT

  4. 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...... genetic relatedness and spatial and temporal distances. Neighbor-joining phylogeography revealed that virus circulating in Bangladesh from 2007 through 2010 belonged to clade 2.2. The results suggest that clade 2.2 viruses are firmly entrenched and have probably become endemic in Bangladesh. We detected...... 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...

  5. Isolation of Highly Pathogenic Avian Influenza H5N1 Virus from Saker Falcons (Falco cherrug in the Middle East

    Directory of Open Access Journals (Sweden)

    Henju Marjuki

    2009-01-01

    Full Text Available There is accumulating evidence that birds of prey are susceptible to fatal infection with highly pathogenic avian influenza (HPAI virus. We studied the antigenic, molecular, phylogenetic, and pathogenic properties of 2 HPAI H5N1 viruses isolated from dead falcons in Saudi Arabia and Kuwait in 2005 and 2007, respectively. Phylogenetic and antigenic analyses grouped both isolates in clade 2.2 (Qinghai-like viruses. However, the viruses appeared to have spread westward via different flyways. It remains unknown how these viruses spread so rapidly from Qinghai after the 2005 outbreak and how they were introduced into falcons in these two countries. The H5N1 outbreaks in the Middle East are believed by some to be mediated by wild migratory birds. However, sporting falcons may be at additional risk from the illegal import of live quail to feed them.

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

    Science.gov (United States)

    Si, Yali; de Boer, Willem F; Gong, Peng

    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. However, previous studies found no difference between these two outbreak types when only the effect of physical environmental factors was analysed. The influence of physical and anthropogenic environmental variables and interactions between the two has only been investigated for wild bird outbreaks. We therefore tested the effect of these environmental factors on HPAI H5N1 outbreaks in poultry, and the potential spread mechanism, and discussed how these differ from those observed in wild birds. Logistic regression analyses were used to quantify the relationship between HPAI H5N1 outbreaks in poultry and environmental factors. Poultry outbreaks increased with an increasing human population density combined with close proximity to lakes or wetlands, increased temperatures and reduced precipitation during the cold season. A risk map was generated based on the identified key factors. In wild birds, outbreaks were strongly associated with an increased Normalized Difference Vegetation Index (NDVI) and lower elevation, though they were similarly affected by climatic conditions as poultry outbreaks. This is the first study that analyses the differences in environmental drivers and spread mechanisms between poultry and wild bird outbreaks. Outbreaks in poultry mostly occurred in areas where the location of farms or trade areas overlapped with habitats for wild birds, whereas outbreaks in wild birds were mainly found in areas where food and shelters are available. The different environmental drivers suggest that different spread mechanisms might be involved: HPAI H5N1 spread to poultry via both poultry and wild birds, whereas contact with wild birds alone seems to drive the outbreaks

  7. 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.

  8. 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; Fonseca, Kevin; Tipples, Graham A

    2014-05-01

    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.

  9. Critical control points for avian influenza A H5N1 in live bird markets in low resource settings.

    Science.gov (United States)

    Samaan, Gina; Gultom, Anita; Indriani, Risa; Lokuge, Kamalini; Kelly, Paul M

    2011-06-01

    Live bird markets can become contaminated with and become a source of transmission for avian influenza viruses including the highly pathogenic H5N1 strain. Many countries affected by the H5N1-virus have limited resources for programs in environmental health, sanitation and disease control in live bird markets. This study proposes five critical control points (CCPs) to reduce the risk of H5N1-virus contamination in markets in low resource settings. The CCPs were developed based on three surveys conducted in Indonesia: a cross-sectional survey in 119 markets, a knowledge, attitudes and practice survey in 3 markets and a microbiological survey in 83 markets. These surveys assessed poultry workflow, market infrastructure, hygiene and regulatory practices and microbiological contamination with the H5N1-virus. The five CCPs identified were (1) reducing risk of receiving infected birds into the market, (2) reducing the risk of virus spread between different bird flocks in holding cages, (3) reducing surface contamination by isolating slaughter processes from other poultry-related processes, (4) minimizing the potential for contamination during evisceration of carcasses and (5) reducing the risk of surface contamination in the sale zone of the market. To be relevant for low resource settings, the CCPs do not necessitate large infrastructure changes. The CCPs are suited for markets that slaughter poultry and have capacity for daily disposal and removal of solid waste from the market. However, it is envisaged that the CCPs can be adapted for the development of risk-based programs in various settings.

  10. Migratory status is not related to the susceptibility to HPAIV H5N1 in an insectivorous passerine species.

    Directory of Open Access Journals (Sweden)

    Donata Kalthoff

    Full Text Available Migratory birds have evolved elaborate physiological adaptations to travelling, the implications for their susceptibility to avian influenza are however unknown. Three groups of stonechats (Saxicola torquata from (I strongly migrating, (II weakly migrating and (III non-migrating populations were experimentally infected with HPAIV H5N1. The different bird groups of this insectivorous passerine species were infected in autumn, when the migrating populations clearly exhibit migratory restlessness. Following infection, all animals succumbed to the disease from 3 through 7 days post inoculation. Viral shedding, antigen distribution in tissues, and survival time did not differ between the three populations. However, notably, endothelial tropism of the HPAIV infection was exclusively seen in the group of resident birds. In conclusion, our data document for the first time the high susceptibility of an insectivorous passerine species to H5N1 infection, and the epidemiological role of these passerine birds is probably limited due to their high sensitivity to HPAIV H5N1 infection. Despite pronounced inherited differences in migratory status, the groups were generally indistinguishable in their susceptibility, survival time, clinical symptoms and viral shedding. Nevertheless, the migratory status partly influenced pathogenesis in the way of viral tropism.

  11. Defining "Sector 3" Poultry Layer Farms in Relation to H5N1-HPAI-An Example from Java, Indonesia.

    Science.gov (United States)

    Durr, Peter A; Wibowo, Michael Haryadi; Tarigan, Simson; Artanto, Sidna; Rosyid, Murni Nurhasanah; Ignjatovic, Jagoda

    2016-05-01

    To help guide surveillance and control of highly pathogenic avian influenza subtype H5N1 (H5N1-HPAI), the Food and Agriculture Organization of the United Nations in 2004 devised a poultry farm classification system based on a combination of production and biosecurity practices. Four "Sectors" were defined, and this scheme has been widely adopted within Indonesia to guide national surveillance and control strategies. Nevertheless, little detailed research into the robustness of this classification system has been conducted, particularly as it relates to independent, small to medium-sized commercial poultry farms (Sector 3). Through an analysis of questionnaire data collected as part of a survey of layer farms in western and central Java, all of which were classified as Sector 3 by local veterinarians, we provide benchmark data on what defines this sector. A multivariate analysis of the dataset, using hierarchical cluster analysis, identified three groupings of the farms, which were defined by a combination of production-and biosecurity-related variables, particularly those related to farm size and (the lack of) washing and disinfection practices. Nevertheless, the relationship between production-related variables and positive biosecurity practices was poor, and larger farms did not have an overall higher total biosecurity score than small or medium-sized ones. Further research is required to define the properties of poultry farms in Indonesia that are most closely related to effective biosecurity and the prevention of H5N1-HPAI.

  12. A unique influenza A (H5N1 virus causing a focal poultry outbreak in 2007 in Manipur, India

    Directory of Open Access Journals (Sweden)

    Raut Satish

    2009-02-01

    Full Text Available Abstract Background A focal H5N1 outbreak in poultry was reported from Manipur, a north-eastern state, of India, in 2007. The aim of this study was to genetically characterize the Manipur isolate to understand the relationship with other H5N1 isolates and to trace the possible source of introduction of the virus into the country. Results Characterization of the complete genome revealed that the virus belonged to clade 2.2. It was distinctly different from viruses of the three EMA sublineages of clade 2.2 but related to isolates from wild migratory waterfowl from Russia, China and Mongolia. The HA gene, had the cleavage site GERRRRKR, earlier reported in whooper swan isolates from Mongolia in 2005. A stop codon at position 29 in the PB1-F2 protein could have implications on the replication efficiency. The acquisition of polymorphisms as seen in recent isolates of 2005–07 from distinct geographical regions suggests the possibility of transportation of H5N1 viruses through migratory birds. Conclusion Considering that all eight genes of the earlier Indian isolates belonged to the EMA3 sublineage and similar strains have not been reported from neighbouring countries of the subcontinent, it appears that the virus may have been introduced independently.

  13. Two glycosylation sites in H5N1 influenza virus hemagglutinin that affect binding preference by computer-based analysis.

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    Wentian Chen

    Full Text Available Increasing numbers of H5N1 influenza viruses (IVs are responsible for human deaths, especially in North Africa and Southeast Asian. The binding of hemagglutinin (HA on the viral surface to host sialic acid (SA receptors is a requisite step in the infection process. Phylogenetic analysis reveals that H5N1 viruses can be divided into 10 clades based on their HA sequences, with most human IVs centered from clade 1 and clade 2.1 to clade 2.3. Protein sequence alignment in various clades indicates the high conservation in the receptor-binding domains (RBDs is essential for binding with the SA receptor. Two glycosylation sites, 158N and 169N, also participate in receptor recognition. In the present work, we attempted to construct a serial H5N1 HA models including diverse glycosylated HAs to simulate the binding process with various SA receptors in silico. As the SA-α-2,3-Gal and SA-α-2,6-Gal receptor adopted two distinctive topologies, straight and fishhook-like, respectively, the presence of N-glycans at 158N would decrease the affinity of HA for all of the receptors, particularly SA-α-2,6-Gal analogs. The steric clashes of the huge glycans shown at another glycosylation site, 169N, located on an adjacent HA monomer, would be more effective in preventing the binding of SA-α-2,3-Gal analogs.

  14. Risk-based surveillance for H5N1 avian influenza virus in wild birds in Great Britain.

    Science.gov (United States)

    Snow, L C; Newson, S E; Musgrove, A J; Cranswick, P A; Crick, H Q P; Wilesmith, J W

    2007-12-01

    Recent outbreaks of the H5N1 strain of avian influenza in Europe have highlighted the need for continuous surveillance and early detection to reduce the likelihood of a major outbreak in the commercial poultry industry. In Great Britain (gb), one possible route by which H5N1 could be introduced into domestic poultry is through migratory wild birds from Europe and Asia. Extensive monitoring data on the 24 wild bird species considered most likely to introduce the virus into GB, and analyses of local poultry populations, were used to develop a risk profile to identify the areas where H5N1 is most likely to enter and spread to commercial poultry. The results indicate that surveillance would be best focused on areas of Norfolk, Suffolk, Lancashire, Lincolnshire, south-west England and the Welsh borders, with areas of lower priority in Anglesey, south-west Wales, north-east Aberdeenshire and the Firth of Forth area of Scotland. These areas have significant poultry populations including a large number of free-range flocks, and a high abundance of the 24 wild bird species.

  15. Spatio-temporal epidemiology of highly pathogenic avian influenza (subtype H5N1) in poultry in eastern India.

    Science.gov (United States)

    Dhingra, Madhur S; Dissanayake, Ravi; Negi, Ajender Bhagat; Oberoi, Mohinder; Castellan, David; Thrusfield, Michael; Linard, Catherine; Gilbert, Marius

    2014-10-01

    In India, majority outbreaks of highly pathogenic avian influenza (HPAI) H5N1 have occurred in eastern states of West Bengal, Assam and Tripura. This study aimed to identify disease clusters and risk factors of HPAI H5N1 in these states, for targeted surveillance and disease control. A spatial scan statistic identified two significant disease clusters in West Bengal and Assam, occurring during January and November-December 2008, respectively. Key risk factors were identified at sub-district level using bootstrapped logistic regression and boosted regression trees model. With both methods, HPAI H5N1 outbreaks in backyard poultry were associated with accessibility in terms of time taken to access a city with >50,000 persons, human population density and duck density (P<0.005). In addition, areas at lower elevation were also identified as high risk by BRT model. It is recommended that risk-based surveillance should be implemented in high duck density areas and all live-bird markets in high-throughput locations.

  16. 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.

  17. Pathology of natural highly pathogenic avian influenza H5N1 infection in wild tufted ducks (Aythya fuligula).

    Science.gov (United States)

    Bröjer, Caroline; Agren, Erik O; Uhlhorn, Henrik; Bernodt, Karin; Mörner, Torsten; Jansson, Désirée S; Mattsson, Roland; Zohari, Siamak; Thorén, Peter; Berg, Mikael; Gavier-Widén, Dolores

    2009-09-01

    Highly pathogenic avian influenza (HPAI) subtype H5N1 is an infectious systemic viral disease that results in high morbidity and mortality in poultry, and has been reported in a wide range of wild bird species during the last few years. An outbreak of HPAI H5N1 occurred in wild birds in Sweden in 2006 that affected several duck species, geese, swans, gulls, and raptors. Tufted ducks (Aythya fuligula) accounted for the largest number of positive cases and, therefore, were selected for more in-depth histologic and immunohistochemical evaluations. The main histologic lesions associated with the presence of avian influenza antigen were found in the brain, pancreas, and upper respiratory tract. Other tissues in which influenza antigen was variably found included liver, lung, adrenal glands, kidneys, and peripheral nerve ganglia. The current study describes the pathology and viral tissue targeting of H5N1 by using histology, polymerase chain reaction, and immunohistochemistry, and highlights the range and variation in the presentation of the natural disease in tufted ducks.

  18. Identification of human host proteins contributing to H5N1 influenza virus propagation by membrane proteomics.

    Science.gov (United States)

    Liu, Cheng; Zhang, Anding; Guo, Jing; Yang, Jing; Zhou, Hongbo; Chen, Huanchun; Jin, Meilin

    2012-11-02

    The highly pathogenic avian influenza (HPAI) H5N1 virus is a highly virulent pathogen that causes respiratory diseases and death in humans and other animal species worldwide. Because influenza is an enveloped virus, the entry, assembly, and budding of virus particles are essential steps in the viral life cycle, and the virus relies on the participation of host cellular membrane proteins for all of these steps. Thus, we took a comparative membrane proteomics approach by using 2-DE coupled with MALDI-TOF/TOF MS to profile membrane proteins involved in H5N1 virus infection at 6, 12, and 24 h. Forty-two different proteins were found to vary on A549 cells due to H5N1 virus infection. Of these proteins, 57% were membrane or membrane-associated proteins. To further characterize the roles of novel identified proteins in virus propagation, the siRNA technology were applied and complement component C1q binding protein, annexin 2, prohibitin, peroxiredoxin 1 and heat shock protein 90-beta were successfully demonstrated to be contributed to viral propagation. In conclusion, the present study provides important new insight into understanding the roles of host membrane proteins in viral infection progress, and this insight is of particular importance for the development of novel therapeutic strategies.