WorldWideScience

Sample records for avian h5n1 influenza

  1. 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.

  2. Atypical Avian Influenza (H5N1)

    OpenAIRE

    Apisarnthanarak, Anucha; Kitphati, Rungrueng; Thongphubeth, Kanokporn; Patoomanunt, Prisana; Anthanont, Pimjai; Auwanit, Wattana; Thawatsupha, Pranee; Chittaganpitch, Malinee; Saeng-Aroon, Siriphan; Waicharoen, Sunthareeya; Apisarnthanarak, Piyaporn; Storch, Gregory A.; Mundy, Linda M.; Fraser, Victoria J.

    2004-01-01

    We report the first case of avian influenza in a patient with fever and diarrhea but no respiratory symptoms. Avian influenza should be included in the differential diagnosis for patients with predominantly gastrointestinal symptoms, particularly if they have a history of exposure to poultry.

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

    Science.gov (United States)

    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. PMID:24491922

  4. 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.

  5. 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.

  6. 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.

  7. Fatal Avian Influenza A H5N1 in a Dog

    OpenAIRE

    Songserm, Thaweesak; Amonsin, Alongkorn; Jam-on, Rungroj; Sae-Heng, Namdee; Pariyothorn, Nuananong; Payungporn, Sunchai; Theamboonlers, Apiradee; Chutinimitkul, Salin; Thanawongnuwech, Roongroje; Poovorawan, Yong

    2006-01-01

    Avian influenza H5N1 virus is known to cross the species barrier and infect humans and felines. We report a fatal H5N1 infection in a dog following ingestion of an H5N1-infected duck during an outbreak in Thailand in 2004. With new reports of H5N1 virus continuing across Asia, Europe, and Africa, this finding highlights the need for monitoring of domestic animals during outbreaks.

  8. Protection from avian influenza H5N1 virus infection with antibody-impregnated filters

    Directory of Open Access Journals (Sweden)

    Tsukamoto Masaya

    2011-02-01

    Full Text Available Abstract There is worldwide concern over the possibility of a new influenza pandemic originating from the highly pathogenic avian H5N1 influenza viruses. We herein demonstrate that functional air filters impregnated with ostrich antibodies against the hemagglutinin of the H5N1 virus protect chickens from death by H5N1 transmission. These results suggest that the use of ostrich antibody-impregnated filters might be a powerful way to prevent the transmission of H5N1.

  9. 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.

  10. Avian Influenza A(H5N1) Virus in Egypt

    Science.gov (United States)

    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.

    2016-01-01

    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. PMID:26886164

  11. Avian influenza A (H5N1) infection in a patient in China, 2006

    Science.gov (United States)

    Chen, X.; Smith, G.J.D.; Zhou, B.; Qiu, C.; Wu, W.L.; Li, Y.; Lu, P.; Duan, L.; Liu, S.; Yuan, J.; Yang, G.; Wang, H.; Cheng, J.; Jiang, H.; Peiris, J.S.M.; Chen, H.; Yuen, K.Y.; Zhong, N.; Guan, Y.

    2008-01-01

    Background  Highly pathogenic avian influenza H5N1 virus has caused increasing human infection in Eurasia since 2004. So far, H5N1 human infection has been associated with over 50% mortality that is partly because of delay of diagnosis and treatment. Objectives and methods  Here, we report that an H5N1 influenza virus infected a 31‐year‐old patient in Shenzhen in June 2006. To identify the possible source of the infection, the human isolate and other H5N1 influenza viruses obtained from poultry and wild birds in southern China during the same period of time were characterized. Results  Genetic and antigenic analyses revealed that the human H5N1 influenza virus, Shenzhen/406H/06, is of purely avian origin and is most closely related to viruses detected in poultry and wild birds in Hong Kong in early 2006. Conclusions  The findings of the present study suggest that the continued endemicity of H5N1 influenza virus in the poultry in southern China increases the chance for introduction of the virus to humans. This highlights the importance of continued surveillance of poultry and wild birds for determining the source for human H5N1 infection. PMID:19453428

  12. 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.

  13. 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.

  14. 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...

  15. 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.

  16. Highly pathogenic avian influenza (H5N1) outbreaks in wild birds and poultry, South Korea.

    Science.gov (United States)

    Kim, Hye-Ryoung; Lee, Youn-Jeong; Park, Choi-Kyu; Oem, Jae-Ku; Lee, O-Soo; Kang, Hyun-Mi; Choi, Jun-Gu; Bae, You-Chan

    2012-03-01

    Highly pathogenic avian influenza (H5N1) among wild birds emerged simultaneously with outbreaks in domestic poultry in South Korea during November 2010-May 2011. Phylogenetic analysis showed that these viruses belonged to clade 2.3.2, as did viruses found in Mongolia, the People's Republic of China, and Russia in 2009 and 2010.

  17. Highly Pathogenic Avian Influenza (H5N1) Outbreaks in Wild Birds and Poultry, South Korea

    OpenAIRE

    Kim, Hye-Ryoung; Lee, Youn-Jeong; Park, Choi-Kyu; Oem, Jae-Ku; Lee, O-Soo; Kang, Hyun-Mi; Choi, Jun-Gu; Bae, You-Chan

    2012-01-01

    Highly pathogenic avian influenza (H5N1) among wild birds emerged simultaneously with outbreaks in domestic poultry in South Korea during November 2010–May 2011. Phylogenetic analysis showed that these viruses belonged to clade 2.3.2, as did viruses found in Mongolia, the People’s Republic of China, and Russia in 2009 and 2010.

  18. 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

  19. Pathogenicity, Transmission and Antigenic Variation of H5N1 Highly Pathogenic Avian Influenza Viruses

    Science.gov (United States)

    Jiao, Peirong; Song, Hui; Liu, Xiaoke; Song, Yafen; Cui, Jin; Wu, Siyu; Ye, Jiaqi; Qu, Nanan; Zhang, Tiemin; Liao, Ming

    2016-01-01

    H5N1 highly pathogenic avian influenza (HPAI) was one of the most important avian diseases in poultry production of China, especially in Guangdong province. In recent years, new H5N1 highly pathogenic avian influenza viruses (HPAIV) still emerged constantly, although all poultry in China were immunized with H5N1 vaccinations compulsorily. To better understand the pathogenicity and transmission of dominant clades of the H5N1 HPAIVs in chicken from Guangdong in 2012, we chose a clade 7.2 avian influenza virus named A/Chicken/China/G2/2012(H5N1) (G2) and a clade 2.3.2.1 avian influenza virus named A/Duck/China/G3/2012(H5N1) (G3) in our study. Our results showed that the chickens inoculated with 103 EID50 of G2 or G3 viruses all died, and the titers of virus replication detected in several visceral organs were high but different. In the naive contact groups, virus shedding was not detected in G2 group and all chickens survived, but virus shedding was detected in G3 group and all chickens died. These results showed that the two clades of H5N1 HPAIVs had high pathogenicity in chickens and the contact transmission of them was different in chickens. The results of cross reactive HI assay showed that antigens of G2 and G3 were very different from those of current commercial vaccines isolates (Re-4, Re-6, and D7). And to evaluate the protective efficacy of three vaccines against most isolates form Guangdong belonging to clade 2.3.2.1 in 2012, G3 was chosen to challenge the three vaccines such as Re-4, Re-6, and D7. First, chickens were immunized with 0.3 ml Re-4, Re-6, and D7 inactivated vaccines by intramuscular injection, respectively, and then challenged with 106 EID50 of G3 on day 28 post-vaccination. The D7 vaccine had 100% protection against G3 for chickens, the Re-6 vaccine had 88.9%, and the Re-4 vaccine only had 66.7%. Our results suggested that the D7 vaccine could prevent and control H5N1 virus outbreaks more effectively in Guangdong. From the above, it was

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

    Directory of Open Access Journals (Sweden)

    Annemarie Bouma

    2009-01-01

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

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. Population-environment drivers of H5N1 avian influenza molecular change in Vietnam.

    Science.gov (United States)

    Carrel, Margaret A; Emch, Michael; Nguyen, Tung; Todd Jobe, R; Wan, Xiu-Feng

    2012-09-01

    This study identifies population and environment drivers of genetic change in H5N1 avian influenza viruses (AIV) in Vietnam using a landscape genetics approach. While prior work has examined how combinations of local-level environmental variables influence H5N1 occurrence, this research expands the analysis to the complex genetic characteristics of H5N1 viruses. A dataset of 125 highly pathogenic H5N1 AIV isolated in Vietnam from 2003 to 2007 is used to explore which population and environment variables are correlated with increased genetic change among viruses. Results from non-parametric multidimensional scaling and regression analyses indicate that variables relating to both the environmental and social ecology of humans and birds in Vietnam interact to affect the genetic character of viruses. These findings suggest that it is a combination of suitable environments for species mixing, the presence of high numbers of potential hosts, and in particular the temporal characteristics of viral occurrence, that drive genetic change among H5N1 AIV in Vietnam. PMID:22652510

  6. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. 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. PMID:26900963

  9. Phylogenetic analysis of Neuraminidase gene of avian influenza H5N1 subtype detected in Iran in 1390(2011)

    OpenAIRE

    E Kord; Shoushtari, A.; H Ghadakchi; MOHAMMADI, R.; A ,Hadinia

    2013-01-01

    Abstract Background & aim: Among the various subtypes of avian influenza viruses, an H5N1 subtype virus with high pathogenicity is of great importance. The aim of this study was to determine the Phylogenetic analysis of neuraminidase gene of avian influenza virus subtype of the H5N1 in Iran in 1390. Methods: In this experimental study, two swab samples from chickens with suspected symptoms of avian influenza were tested by the World Health Organization recommendation. The neuraminidase...

  10. 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...

  11. 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

  12. 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.

  13. 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...

  14. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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.

  17. Avian Flu School: A Training Approach to Prepare for H5N1 Highly Pathogenic Avian Influenza

    OpenAIRE

    Beltran-Alcrudo, Daniel; Bunn, David A.; Sandrock, Christian E.; Cardona, Carol J.

    2008-01-01

    Since the reemergence of highly pathogenic avian influenza (H5N1 HPAI) in 2003, a panzootic that is historically unprecedented in the number of infected flocks, geographic spread, and economic consequences for agriculture has developed. The epidemic has affected a wide range of birds and mammals, including humans. The ineffective management of outbreaks, mainly due to a lack of knowledge among those involved in detection, prevention, and response, points to the need for training on H5N1 HPAI....

  18. 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...

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

    Science.gov (United States)

    Arafa, A; Suarez, D; Kholosy, S G; Hassan, M K; Nasef, S; Selim, A; Dauphin, G; Kim, M; Yilma, J; Swayne, D; Aly, M M

    2012-10-01

    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 as a part of the control strategy to help to control the disease. Epidemiological data with sequence analysis of H5N1 viruses is important to link the mechanism of virus evolution in Egypt. This study describes the evolutionary pattern of Egyptian H5N1 viruses based on molecular characterization for the isolates collected from commercial poultry farms and village poultry from 2006 to 2011. Genetic analysis of the hemagglutinin (HA) gene was done by sequencing of the full-length H5 gene. The epidemiological pattern of disease outbreaks in Egyptian poultry farms seems to be seasonal with no specific geographic distribution across the country. The molecular epidemiological data revealed that there are two major groups of viruses: the classic group of subclade 2.2.1 and a variant group of 2.2.1.1. The classic group is prevailing mainly in village poultry and had fewer mutations compared to the originally introduced virus in 2006. Since 2009, this group has started to be transmitted back to commercial sectors. The variant group emerged by late 2007, was prevalent mainly in vaccinated commercial poultry, mutated continuously at a higher rate until 2010, and started to decline in 2011. Genetic analysis of the neuraminidase (NA) gene and the other six internal genes indicates a grouping of the Egyptian viruses similar to that obtained using the HA gene, with no obvious reassortments. The results of this study indicate that HPAI-H5N1 viruses are progressively evolving and adapting in Egypt and continue to acquire new mutations every season. PMID:22760662

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

    Directory of Open Access Journals (Sweden)

    Li-Qun Fang

    Full Text Available BACKGROUND: 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 fatalities, have occurred. The unrestrained worldwide spread of this disease has caused great anxiety about the potential of another global pandemic. However, the effect of environmental factors influencing the spread of HPAI H5N1 virus is unclear. METHODOLOGY/PRINCIPAL FINDINGS: A database including incident dates and locations was developed for 128 confirmed HPAI H5N1 outbreaks in poultry and wild birds, as well as 21 human cases in mainland China during 2004-2006. These data, together with information on wild bird migration, poultry densities, and environmental variables (water bodies, wetlands, transportation routes, main cities, precipitation and elevation, were integrated into a Geographical Information System (GIS. A case-control design was used to identify the environmental factors associated with the incidence of the disease. Multivariate logistic regression analysis indicated that minimal distance to the nearest national highway, annual precipitation and the interaction between minimal distance to the nearest lake and wetland, were important predictive environmental variables for the risk of HPAI. A risk map was constructed based on these factors. CONCLUSIONS/SIGNIFICANCE: Our study indicates that environmental factors contribute to the spread of the disease. The risk map can be used to target countermeasures to stop further spread of the HPAI H5N1 at its source.

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

    Directory of Open Access Journals (Sweden)

    Syed S U Ahmed

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

  2. 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...

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

    International Nuclear Information System (INIS)

    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. (paper)

  4. Highly pathogenic avian influenza H5N1 virus delays apoptotic responses via activation of STAT3.

    Science.gov (United States)

    Hui, Kenrie P Y; Li, Hung Sing; Cheung, Man Chun; Chan, Renee W Y; Yuen, Kit M; Mok, Chris K P; Nicholls, John M; Peiris, J S Malik; Chan, Michael C W

    2016-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 virus continues to pose pandemic threat, but there is a lack of understanding of its pathogenesis. We compared the apoptotic responses triggered by HPAI H5N1 and low pathogenic H1N1 viruses using physiologically relevant respiratory epithelial cells. We demonstrated that H5N1 viruses delayed apoptosis in primary human bronchial and alveolar epithelial cells (AECs) compared to H1N1 virus. Both caspase-8 and -9 were activated by H5N1 and H1N1 viruses in AECs, while H5N1 differentially up-regulated TRAIL. H5N1-induced apoptosis was reduced by TRAIL receptor silencing. More importantly, STAT3 knock-down increased apoptosis by H5N1 infection suggesting that H5N1 virus delays apoptosis through activation of STAT3. Taken together, we demonstrate that STAT3 is involved in H5N1-delayed apoptosis compared to H1N1. Since delay in apoptosis prolongs the duration of virus replication and production of pro-inflammatory cytokines and TRAIL from H5N1-infected cells, which contribute to orchestrate cytokine storm and tissue damage, our results suggest that STAT3 may play a previously unsuspected role in H5N1 pathogenesis. PMID:27344974

  5. Highly pathogenic avian influenza H5N1 virus delays apoptotic responses via activation of STAT3

    Science.gov (United States)

    Hui, Kenrie P. Y.; Li, Hung Sing; Cheung, Man Chun; Chan, Renee W. Y.; Yuen, Kit M.; Mok, Chris K. P.; Nicholls, John M.; Peiris, J. S. Malik; Chan, Michael C. W.

    2016-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 virus continues to pose pandemic threat, but there is a lack of understanding of its pathogenesis. We compared the apoptotic responses triggered by HPAI H5N1 and low pathogenic H1N1 viruses using physiologically relevant respiratory epithelial cells. We demonstrated that H5N1 viruses delayed apoptosis in primary human bronchial and alveolar epithelial cells (AECs) compared to H1N1 virus. Both caspase-8 and -9 were activated by H5N1 and H1N1 viruses in AECs, while H5N1 differentially up-regulated TRAIL. H5N1-induced apoptosis was reduced by TRAIL receptor silencing. More importantly, STAT3 knock-down increased apoptosis by H5N1 infection suggesting that H5N1 virus delays apoptosis through activation of STAT3. Taken together, we demonstrate that STAT3 is involved in H5N1-delayed apoptosis compared to H1N1. Since delay in apoptosis prolongs the duration of virus replication and production of pro-inflammatory cytokines and TRAIL from H5N1-infected cells, which contribute to orchestrate cytokine storm and tissue damage, our results suggest that STAT3 may play a previously unsuspected role in H5N1 pathogenesis. PMID:27344974

  6. Survivability of Eurasian H5N1 highly pathogenic avian influenza viruses in water varies between strains

    Science.gov (United States)

    Aquatic habitats play critical role in the transmission and maintenance of low pathogenic avian influenza (LPAI) viruses in wild waterfowl; however the importance of these environments in the ecology of H5N1 highly pathogenic avian influenza (HPAI) viruses is unknown. In laboratory-based studies, L...

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

    DEFF Research Database (Denmark)

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

    2011-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Kelly Edmunds

    2009-06-01

    Full Text Available Wildlife trade and emerging infectious diseases pose significant threats to human and animal health and global biodiversity. Legal and illegal trade in domestic and wild birds has played a significant role in the global spread of highly pathogenic avian influenza H5N1, which has killed more than 240 people, many millions of poultry, and an unknown number of wild birds and mammals, including endangered species, since 2003. This 2007 study provides evidence for a significant decline in the scale of the wild bird trade in Hanoi since previous surveys in 2000 (39.7% decline and 2003 (74.1% decline. We attribute this to the enforcement of Vietnam's Law 169/2005/QD UBND, introduced in 2005, which prohibits the movement and sale of wild and ornamental birds in cities. Nevertheless, 91.3% (21/23 of bird vendors perceived no risk of H5N1 infection from their birds, and the trade continues, albeit at reduced levels, in open market shops. These findings highlight the importance of continued law enforcement to maintain this trade reduction and the associated benefits to human and animal health and biodiversity conservation.

  9. The financial cost implications of the highly pathogenic notifiable avian influenza H5N1 in Nigeria

    OpenAIRE

    Fasina, F.O.; M.M. Sirdar; S.P.R. Bisschop

    2008-01-01

    Nigeria and several other nations have recently been affected by outbreaks of the Asian H5N1 strain of highly pathogenic notifiable avian influenza (HPNAI) virus, which affects the poultry sector most heavily. This study analysed previous methods of assessing losses due to avian influenza, and used a revised economic model to calculate costs associated with the current avian influenza outbreaks. The evaluation used epidemiological data, production figures and other input parameters to d...

  10. 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.

  11. 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.

  12. 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

  13. Persistence of Highly Pathogenic Avian Influenza H5N1 Virus Defined by Agro-Ecological Niche

    OpenAIRE

    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...

  14. Pathogenicity of recombinant H5N1 avian influenza viruses with truncated NS1 gene in chickens

    Science.gov (United States)

    The NS1 protein of influenza A virus plays an important role in blocking the induction of type I interferon and other regulatory functions in infected cells. However, differences in length of the NS1 protein has been observed in highly pathogenic H5N1, H5N2, and H7N1 subtype avian influenza viruses...

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

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

    International Nuclear Information System (INIS)

    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

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

    OpenAIRE

    Peterson A Townsend; Williams Richard AJ

    2009-01-01

    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...

  18. Heterosubtypic anti-avian H5N1 influenza antibodies in intravenous immunoglobulins from globally separate populations protect against H5N1 infection in cell culture

    OpenAIRE

    Sullivan, John S.; Selleck, Paul W.; Downton, Teena; Boehm, Ingrid; Axell, Anna-Maree; Ayob, Yasmin; Kapitza, Natalie M; Dyer, Wayne; Fitzgerald, Anna; Walsh, Bradley; Lynch, Garry W

    2009-01-01

    With antigenically novel epidemic and pandemic influenza strains persistently on the horizon it is of fundamental importance that we understand whether heterosubtypic antibodies gained from exposures to circulating human influenzas exist and can protect against emerging novel strains. Our studies of IVIG obtained from an infection-naive population (Australian) enabled us to reveal heterosubtypic influenza antibodies that cross react with H5N1. We now expand those findings for an Australian do...

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

    Directory of Open Access Journals (Sweden)

    Xiu-Feng Wan

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

  20. 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.

  1. Highly pathogenic avian influenza (H5N1: pathways of exposure at the animal-human interface, a systematic review.

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    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

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

    Directory of Open Access Journals (Sweden)

    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

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

    OpenAIRE

    Setiawaty V; Pangesti KN; Sampurno OD

    2012-01-01

    Vivi Setiawaty, Krisna NA Pangesti, Ondri D SampurnoNational Institute of Health Research and Development, Ministry of Health, the Republic of Indonesia, Jakarta, IndonesiaAbstract: Indonesia has been part of the global influenza surveillance since the establishment of a National Influenza Center (NIC) at the National Institute of Health Research and Development (NIHRD) by the Indonesian Ministry of Health in 1975. When the outbreak of avian influenza A (H5N1) occurred, the NIC and US Naval M...

  4. Mechanisms of transmission and spread of H5N1 high pathogenicity avian influenza virus in birds and mammals

    Science.gov (United States)

    The Eurasian-African H5N1 high pathogenicity avian influenza (HPAI) virus has crossed multiple species barriers to infect poultry, captive and wild birds, carnivorous mammals and humans. The specific transmission mechanisms are unclear in most cases, but experimental studies and field data sug...

  5. 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

  6. Wild ducks as long-distance vectors of highly pathogenic avian influenza virus (H5N1)

    NARCIS (Netherlands)

    J. Keawcharoen (Juthatip); D.A.J. van Riel (Debby); G. van Amerongen (Geert); T.M. Bestebroer (Theo); W.E.Ph. Beyer (Walter); R.F. van Lavieren (Rob); A.D.M.E. Osterhaus (Albert); R.A.M. Fouchier (Ron); T. Kuiken (Thijs)

    2008-01-01

    textabstractWild birds have been implicated in the expansion of highly pathogenic avian influenza virus (H5N1) outbreaks across Asia, the Middle East, Europe, and Africa (in addition to traditional transmission by infected poultry, contaminated equipment, and people). Such a role would require wild

  7. 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

  8. 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.

  9. 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.

  10. 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.

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

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    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

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

    DEFF Research Database (Denmark)

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

    2012-01-01

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

  13. Development of a sensitive novel diagnostic kit for the highly pathogenic avian influenza A (H5N1) virus

    OpenAIRE

    Tsunetsugu-Yokota, Yasuko; Nishimura, Kengo; Misawa, Shuhei; Kobayashi-Ishihara, Mie; Takahashi, Hitoshi; Takayama, Ikuyo; Ohnishi, Kazuo; Itamura, Shigeyuki; Nguyen, Hang LK; Le, Mai TQ; Dang, Giang T; Nguyen, Long T; Tashiro, Masato; Kageyama, Tsutomu

    2014-01-01

    Background Sporadic emergence of the highly pathogenic avian influenza (HPAI) H5N1 virus infection in humans is a serious concern because of the potential for a pandemic. Conventional or quantitative RT-PCR is the standard laboratory test to detect viral influenza infections. However, this technology requires well-equipped laboratories and highly trained personnel. A rapid, sensitive, and specific alternative screening method is needed. Methods By a luminescence-linked enzyme immunoassay, we ...

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

    Directory of Open Access Journals (Sweden)

    Sharifa Nasreen

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

  15. 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.

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

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    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.

  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. Genetic evidence for avian influenza H5N1 viral transmission along the Black Sea-Mediterranean Flyway.

    Science.gov (United States)

    Zhou, Sen; Tian, Huaiyu; Wu, Xiaoxu; Xu, Bo; Yang, Jing; Chan, Karen Kie Yan; Huang, Shanqian; Dong, Lu; Brownstein, John; Xu, Bing

    2016-09-01

    The current epidemic of highly pathogenic avian influenza H5N1 virus is considered to pose a significant threat to the health of wild and domestic avian species, and even to human beings. The Black Sea-Mediterranean Flyway is one of the most important epidemic areas of H5N1. However, the epidemic along this flyway has not been fully explored. To better understand the role of hosts in the spread and evolution of H5N1 virus along the flyway, a phylogeographic study was conducted using haemagglutinin (HA) gene sequences obtained during 2005-2013. To infer phylodynamic spread in time and space, we used a flexible Bayesian statistical framework and modelled viral spatial diffusion as a continuous-time Markov-chain process along time-measured genealogies. Our results revealed that H5N1 virus isolated from wild birds showed an increase in genetic variation of HA gene from 2005-2007. The mean genetic distance of viruses isolated from poultry reached its peak in 2010, and dropped in 2011, increasing again in 2012-2013. The reconstruction of virus circulation revealed a different viral-migration network of H5N1 virus by different hosts. Western Russia constituted a link in viral migration from Russia to Europe and Africa. Cross-species transmission of H5N1 viruses predominated in the migration network of the Black Sea-Mediterranean Flyway. This might be due to the migration of birds across long distances and interaction between local poultry and migratory birds. Additionally, the short-distance spread of H5N1 viruses among poultry followed local transportation networks. Such findings will aid in developing effective disease control and prevention strategies.

  19. 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

  20. 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....

  1. 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

  2. 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.

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

    OpenAIRE

    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

    2014-01-01

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

  4. 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...

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

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    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.

  6. 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

    2010-06-01

    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. PMID:20585972

  7. 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.

  8. 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

  9. Intranasal Flu Vaccine Protective against Seasonal and H5N1 Avian Influenza Infections

    Science.gov (United States)

    Alsharifi, Mohammed; Lobigs, Mario; Koskinen, Aulikki; Regner, Matthias; Trinidad, Lee; Boyle, David B.; Müllbacher, Arno

    2009-01-01

    Background Influenza A (flu) virus causes significant morbidity and mortality worldwide, and current vaccines require annual updating to protect against the rapidly arising antigenic variations due to antigenic shift and drift. In fact, current subunit or split flu vaccines rely exclusively on antibody responses for protection and do not induce cytotoxic T (Tc) cell responses, which are broadly cross-reactive between virus strains. We have previously reported that γ-ray inactivated flu virus can induce cross-reactive Tc cell responses. Methodology/Principal Finding Here, we report that intranasal administration of purified γ-ray inactivated human influenza A virus preparations (γ-Flu) effectively induces heterotypic and cross-protective immunity. A single intranasal administration of γ-A/PR8[H1N1] protects mice against lethal H5N1 and other heterotypic infections. Conclusions/Significance Intranasal γ-Flu represents a unique approach for a cross-protective vaccine against both seasonal as well as possible future pandemic influenza A virus infections. PMID:19401775

  10. Intranasal flu vaccine protective against seasonal and H5N1 avian influenza infections.

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    Mohammed Alsharifi

    Full Text Available BACKGROUND: Influenza A (flu virus causes significant morbidity and mortality worldwide, and current vaccines require annual updating to protect against the rapidly arising antigenic variations due to antigenic shift and drift. In fact, current subunit or split flu vaccines rely exclusively on antibody responses for protection and do not induce cytotoxic T (Tc cell responses, which are broadly cross-reactive between virus strains. We have previously reported that gamma-ray inactivated flu virus can induce cross-reactive Tc cell responses. METHODOLOGY/PRINCIPAL FINDING: Here, we report that intranasal administration of purified gamma-ray inactivated human influenza A virus preparations (gamma-Flu effectively induces heterotypic and cross-protective immunity. A single intranasal administration of gamma-A/PR8[H1N1] protects mice against lethal H5N1 and other heterotypic infections. CONCLUSIONS/SIGNIFICANCE: Intranasal gamma-Flu represents a unique approach for a cross-protective vaccine against both seasonal as well as possible future pandemic influenza A virus infections.

  11. Modeling the rapid spread of avian influenza (H5N1) in India.

    Science.gov (United States)

    Rao, Arni S R Srinivasa

    2008-07-01

    Controlling the spread of avian bird flu has become a challenging tasks for Indian agriculture and health administrators. After the first evidence and control of the virus in 2006, the virus attacked five states by January 2008. Based on the evidence of rapid spread of the avian bird flu type H5N1 among the Indian states of Maharashtra, Manipur, and West Bengal, and in the partially affected states of Gujarat and Madhya Pradesh, a model is developed to understand the spread of the virus among birds and the effect of control measures on the dynamics of its spread. We predict that, in the absence of control measures, the total number of infected birds in West Bengal within ten and twenty days after initial discovery of infection were 780,000 and 2.1 million, respectively. When interventions are introduced, these values would have ranged from 65,000 to 225,000 after ten days and from 16,000 to 190,000 after twenty days. We show that the farm and market birds constitute the major proportion of total infected birds, followed by domestic birds and wild birds in West Bengal, where a severe epidemic hit recently. Culling 600,000 birds in ten days might have reduced the current epidemic before it spread extensively. Further studies on appropriate transmission parameters, contact rates of birds, population sizes of poultry and farms are helpful for planning.

  12. Phylogenetic analysis of Neuraminidase gene of avian influenza H5N1 subtype detected in Iran in 1390(2011

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    E Kord

    2013-09-01

    Background & aim: Among the various subtypes of avian influenza viruses, an H5N1 subtype virus with high pathogenicity is of great importance. The aim of this study was to determine the Phylogenetic analysis of neuraminidase gene of avian influenza virus subtype of the H5N1 in Iran in 1390. Methods: In this experimental study, two swab samples from chickens with suspected symptoms of avian influenza were tested by the World Health Organization recommendation. The neuraminidase gene of positive samples was amplified by RT-PCR technique. After sequencing the phylogenetic studies were analyzed using MEGA5 and Megalign. Results: Phylogenetic analysis showed that the virus belongs to the Clade 2.3.2.1 which is highly similar to the viruses that are identified in Mongolia in 2010. Also in the stem of this virus neuraminidase protein a number of 20 amino acid has been deleted at position 69-49. Conclusion: Due to findings of this study, it seems that the virus has entered by migratory wild birds with the origin of Mongolia. Key words: Influenza, Avian, Neuraminidase

  13. 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.

  14. Negotiating equitable access to influenza vaccines: global health diplomacy and the controversies surrounding avian influenza H5N1 and pandemic influenza H1N1.

    OpenAIRE

    Fidler, David P.

    2010-01-01

    As part of the PLoS Medicine series on Global Health Diplomacy, David Fidler provides a case study of the difficult negotiations to increase equitable access to vaccines for highly pathogenic avian influenza A (H5N1) and pandemic 2009 influenza A (H1N1).

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

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    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.

  16. 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.

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

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    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.

  18. Genetic characterization of an H5N1 avian influenza virus from a vaccinated duck flock in Vietnam.

    Science.gov (United States)

    Bui, Vuong Nghia; Ogawa, Haruko; Trinh, Dai Quang; Nguyen, Tham Hong Thi; Pham, Nga Thi; Truong, Duc Anh; Bui, Anh Ngoc; Runstadler, Jonathan; Imai, Kunitoshi; Nguyen, Khong Viet

    2014-10-01

    This study reports the genetic characterization of a highly pathogenic avian influenza virus subtype H5N1 isolated from a moribund domestic duck in central Vietnam during 2012. In the moribund duck's flock, within 6 days after vaccination with a commercial H5N1 vaccine (Re-5) to 59-day-old birds, 120 out of 2,000 ducks died. Genetic analysis revealed a substantial number of mutations in the HA gene of the isolate in comparison with the vaccine strains, Re-1 and Re-5. Similar mutations were also found in selected Vietnamese H5N1 strains isolated since 2009. Mutations in the HA gene involved positions at antigenic sites associated with antibody binding and also neutralizing epitopes, with some of the mutations resulting in the modification of N-linked glycosylation of the HA. Those mutations may be related to the escape of virus from antibody binding and the infection of poultry, interpretations which may be confirmed through a reverse genetics approach. The virus also carried an amino acid substitution in the M2, which conferred a reduced susceptibility to amantadine, but no neuraminidase inhibitor resistance markers were found in the viral NA gene. Additional information including vaccination history in the farm and the surrounding area is needed to fully understand the background of this outbreak. Such understanding and expanded monitoring of the H5N1 influenza viruses circulating in Vietnam is an urgent need to provide updated information to improve effective vaccine strain selection and vaccination protocols, aiding disease control, and biosecurity to prevent H5N1 infection in both poultry and humans. PMID:24880916

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

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    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.

  20. 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.

  1. Spatial Modeling of Wild Bird Risk Factors for Highly Pathogenic A(H5N1) Avian Influenza Virus Transmission.

    Science.gov (United States)

    Prosser, Diann J; Hungerford, Laura L; Erwin, R Michael; Ottinger, Mary Ann; Takekawa, John Y; Newman, Scott H; Xiao, Xiangming; Ellis, Erle C

    2016-05-01

    One of the longest-persisting avian influenza viruses in history, highly pathogenic avian influenza virus (HPAIV) A(H5N1), continues to evolve after 18 yr, advancing the threat of a global pandemic. Wild waterfowl (family Anatidae) are reported as secondary transmitters of HPAIV and primary reservoirs for low-pathogenic avian influenza viruses, yet spatial inputs for disease risk modeling for this group have been lacking. Using geographic information software and Monte Carlo simulations, we developed geospatial indices of waterfowl abundance at 1 and 30 km resolutions and for the breeding and wintering seasons for China, the epicenter of H5N1. Two spatial layers were developed: cumulative waterfowl abundance (WAB), a measure of predicted abundance across species, and cumulative abundance weighted by H5N1 prevalence (WPR), whereby abundance for each species was adjusted based on prevalence values and then totaled across species. Spatial patterns of the model output differed between seasons, with higher WAB and WPR in the northern and western regions of China for the breeding season and in the southeast for the wintering season. Uncertainty measures indicated highest error in southeastern China for both WAB and WPR. We also explored the effect of resampling waterfowl layers from 1 to 30 km resolution for multiscale risk modeling. Results indicated low average difference (less than 0.16 and 0.01 standard deviations for WAB and WPR, respectively), with greatest differences in the north for the breeding season and southeast for the wintering season. This work provides the first geospatial models of waterfowl abundance available for China. The indices provide important inputs for modeling disease transmission risk at the interface of poultry and wild birds. These models are easily adaptable, have broad utility to both disease and conservation needs, and will be available to the scientific community for advanced modeling applications. PMID:27309075

  2. Spatial Modeling of Wild Bird Risk Factors for Highly Pathogenic A(H5N1) Avian Influenza Virus Transmission.

    Science.gov (United States)

    Prosser, Diann J; Hungerford, Laura L; Erwin, R Michael; Ottinger, Mary Ann; Takekawa, John Y; Newman, Scott H; Xiao, Xiangming; Ellis, Erle C

    2016-05-01

    One of the longest-persisting avian influenza viruses in history, highly pathogenic avian influenza virus (HPAIV) A(H5N1), continues to evolve after 18 yr, advancing the threat of a global pandemic. Wild waterfowl (family Anatidae) are reported as secondary transmitters of HPAIV and primary reservoirs for low-pathogenic avian influenza viruses, yet spatial inputs for disease risk modeling for this group have been lacking. Using geographic information software and Monte Carlo simulations, we developed geospatial indices of waterfowl abundance at 1 and 30 km resolutions and for the breeding and wintering seasons for China, the epicenter of H5N1. Two spatial layers were developed: cumulative waterfowl abundance (WAB), a measure of predicted abundance across species, and cumulative abundance weighted by H5N1 prevalence (WPR), whereby abundance for each species was adjusted based on prevalence values and then totaled across species. Spatial patterns of the model output differed between seasons, with higher WAB and WPR in the northern and western regions of China for the breeding season and in the southeast for the wintering season. Uncertainty measures indicated highest error in southeastern China for both WAB and WPR. We also explored the effect of resampling waterfowl layers from 1 to 30 km resolution for multiscale risk modeling. Results indicated low average difference (less than 0.16 and 0.01 standard deviations for WAB and WPR, respectively), with greatest differences in the north for the breeding season and southeast for the wintering season. This work provides the first geospatial models of waterfowl abundance available for China. The indices provide important inputs for modeling disease transmission risk at the interface of poultry and wild birds. These models are easily adaptable, have broad utility to both disease and conservation needs, and will be available to the scientific community for advanced modeling applications.

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

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    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.

  4. Molecular characterization of highly pathogenic H5N1 avian influenza viruses isolated in Sweden in 2006

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    Berg Mikael

    2008-10-01

    Full Text Available Abstract Background The analysis of the nonstructural (NS gene of the highly pathogenic (HP H5N1 avian influenza viruses (AIV isolated in Sweden early 2006 indicated the co-circulation of two sub-lineages of these viruses at that time. In order to complete the information on their genetic features and relation to other HP H5N1 AIVs the seven additional genes of twelve Swedish isolates were amplified in full length, sequenced, and characterized. Results The presence of two sub-lineages of HP H5N1 AIVs in Sweden in 2006 was further confirmed by the phylogenetic analysis of approximately the 95% of the genome of twelve isolates that were selected on the base of differences in geographic location, timing and animal species of origin. Ten of the analyzed viruses belonged to sub-clade 2.2.2. and grouped together with German and Danish isolates, while two 2.2.1. sub-clade viruses formed a cluster with isolates of Egyptian, Italian, Slovenian, and Nigerian origin. The revealed amino acid differences between the two sub-groups of Swedish viruses affected the predicted antigenicity of the surface glycoproteins, haemagglutinin and neuraminidase, rather than the nucleoprotein, polymerase basic protein 2, and polymerase acidic protein, the main targets of the cellular immune responses. The distinctive characteristics between members of the two subgroups were identified and described. Conclusion The comprehensive genetic characterization of HP H5N1 AIVs isolated in Sweden during the spring of 2006 is reported. Our data support previous findings on the coincidental spread of multiple sub-lineage H5N1 HPAIVs via migrating aquatic birds to large distance from their origin. The detection of 2.2.1. sub-clade viruses in Sweden adds further data regarding their spread in the North of Europe in 2006. The close genetic relationship of Swedish isolates sub-clade 2.2.2. to the contemporary German and Danish isolates supports the proposition of the introduction and

  5. 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.

  6. H5N1 Avian Flu (H5N1 Bird Flu)

    Science.gov (United States)

    ... Swine Flu H5N1 - Avian/Bird Flu H5N1 Avian Flu - H5N1 Bird Flu H5N1 is a highly pathogenic avian (bird) flu ... WhiteHouse.gov USA.gov GobiernoUSA.gov BusinessUSA.gov Flu Basics Symptoms (CDC) Prevention (CDC) Treatment (CDC) Vaccination ( ...

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

    Directory of Open Access Journals (Sweden)

    Setiawaty V

    2012-08-01

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

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

    Directory of Open Access Journals (Sweden)

    Sean G. Young

    2016-09-01

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

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

    Science.gov (United States)

    Young, Sean G; Carrel, Margaret; Malanson, George P; Ali, Mohamed A; Kayali, Ghazi

    2016-01-01

    Human outbreaks with avian influenza have been, so far, constrained by poor viral adaptation to non-avian hosts. This could be overcome via co-infection, whereby two strains share genetic material, allowing new hybrid strains to emerge. Identifying areas where co-infection is most likely can help target spaces for increased surveillance. Ecological niche modeling using remotely-sensed data can be used for this purpose. H5N1 and H9N2 influenza subtypes are endemic in Egyptian poultry. From 2006 to 2015, over 20,000 poultry and wild birds were tested at farms and live bird markets. Using ecological niche modeling we identified environmental, behavioral, and population characteristics of H5N1 and H9N2 niches within Egypt. Niches differed markedly by subtype. The subtype niches were combined to model co-infection potential with known occurrences used for validation. The distance to live bird markets was a strong predictor of co-infection. Using only single-subtype influenza outbreaks and publicly available ecological data, we identified areas of co-infection potential with high accuracy (area under the receiver operating characteristic (ROC) curve (AUC) 0.991). PMID:27608035

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

    Science.gov (United States)

    Young, Sean G; Carrel, Margaret; Malanson, George P; Ali, Mohamed A; Kayali, Ghazi

    2016-01-01

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

  11. Avian Influenza H5N1 in Naturally Infected Domestic Cat

    OpenAIRE

    Songserm, Thaweesak; Amonsin, Alongkorn; Jam-on, Rungroj; Sae-Heng, Namdee; Meemak, Noppadol; Pariyothorn, Nuananong; Payungporn, Sunchai; Theamboonlers, Apiradee; Poovorawan, Yong

    2006-01-01

    We report H5N1 virus infection in a domestic cat infected by eating a pigeon carcass. The virus isolated from the pigeon and the cat showed the same cluster as the viruses obtained during the outbreak in Thailand. Since cats are common house pets, concern regarding disease transmission to humans exists.

  12. Genetic evolution analysis of matrix protein 2 gene of avian influenza H5N1 viruses from boundary of Yunnan province

    Institute of Scientific and Technical Information of China (English)

    肖雪

    2013-01-01

    Objective To elucidate the variation in characterizations and genetic evolution of the matrix protein 2 or ion channel protein (M2) genes of avian influenza subtype H5N1 viruses in the boundary region of Yunnan province

  13. 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.

  14. Avian influenza A virus H5N1 causes autophagy-mediated cell death through suppression of mTOR signaling

    Institute of Scientific and Technical Information of China (English)

    Jianhui Ma; Qian Sun; Ruifang Mi; Hongbing Zhang

    2011-01-01

    Of the few avian influenza viruses that have crossed the species barrier to infect humans,the highly pathogenic influenza A (H5N1) strain has claimed the lives of more than half of the infected patients.With largely unknown mechanism of lung injury by H5N1 infection,acute respiratory distress syndrome (ARDS) is the major cause of death among the victims.Here we present the fact that H5N1 caused autophagic cell death through suppression of mTOR signaling.Inhibition of autophagy,either by depletion of autophagy gene Beclinl or by autophagy inhibitor 3-methyladenine (3-MA),significantly reduced H5N1 mediated cell death.We suggest that autophagic cell death may contribute to the development of ARDS in H5N1 influenza patients and inhibition of autophagy could therefore become a novel strategy for the treatment of H5N1 infection.

  15. 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

    between Bangladesh and e. g., Thailand and Vietnam. The primary aim of the current study was to establish ecological determinants associated with the risk of HPAI-H5N1 outbreaks at subdistrict level in Bangladesh. The secondary aim was to explore the performance of two different statistical modeling...... approaches for unmeasured spatially correlated variation. Methodology/Principal Findings: An ecological study at subdistrict level in Bangladesh was performed with 138 subdistricts with HPAI-H5N1 outbreaks during 2007-2008, and 326 subdistricts with no outbreaks. The association between ecological...... to river networks, migratory birds' staging areas and literacy rate in addition to already known risk factors, and clarified that the generalized concept of free grazing duck and duck-rice cultivation interacted ecology are not significant determinants for Bangladesh. These findings will refine current...

  16. Military and Military Medical Support in Highly Pathogenic Avian Influenza (HPAI/H5N1) Pandemic Scenario

    International Nuclear Information System (INIS)

    Avian influenza (Bird flu) is a highly contagious viral disease affecting mainly chickens, turkeys, ducks, other birds and mammals. Reservoirs for HPAI /H5N1 virus are shore birds and waterfowl (asymptomatic, excrete virus in feces for a long periods of time), live bird markets and commercial swine facilities. Virus tends to cycle between pigs and birds. HPAI (H5N1) virus is on every 'top ten' list available for potential agricultural bio-weapon agents. The threat of a HPAI/H5N1 pandemic is a definitively global phenomenon and the response must be global. A number of National plans led to various measures of preventing and dealing with epidemics/pandemics. Lessons learned form the pandemic history indicated essential role of military and military medical support to civil authorities in a crisis situation. Based on International Military Medical Avian Influenza Pandemic workshop (Vienna 2006), an expected scenario would involve 30-50% outpatients, 20-30% hospital admission, 2-3% deaths, 10-20% complicated cases. Activities of civil hospital may be reduced by 50%. Benefits of military support could be in: Transportation of patients (primarily by air); Mass vaccination and provision of all other preventive measures (masks, Tamiflu); Restriction of movements; Infection control of health care facilities; Field hospitals for triage and quarantine, military barracks to treat milder cases and military hospitals for severe cases; Deal with corpses; Stockpiling (vaccines, antiviral, antibiotics, protective equipment, supplies); Training; Laboratories; Ensure public safety, etc. With the aim of minimizing the risk of a pandemic spread by means of rapid and uncomplicated cooperation, an early warning system has to be established to improve surveillance, improve international contacts (WHO, ECDC, CDC), establish Platform for sharing information, close contacts of national and international military and civilian surveillance networks and databases, cooperation between military

  17. Mapping antibody epitopes of the avian H5N1 influenza virus

    OpenAIRE

    Surender Khurana; Suguitan, Amorsolo L.; Yonaira Rivera; Simmons, Cameron P.; Antonio Lanzavecchia; Federica Sallusto; Jody Manischewitz; King, Lisa R.; Kanta Subbarao; Hana Golding

    2009-01-01

    Editors' Summary Background Every winter, millions of people catch influenza, a viral infection of the airways. Most recover quickly but seasonal influenza outbreaks (epidemics) kill about half a million people annually. These epidemics occur because small but frequent changes in the viral proteins (antigens) to which the human immune system responds mean that an immune response produced one year by infection or through vaccination provides only partial protection against influenza the next y...

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

    Directory of Open Access Journals (Sweden)

    Syed S U Ahmed

    Full Text Available BACKGROUND: 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. METHODOLOGY/PRINCIPAL FINDINGS: To determine the magnitude and spatial pattern of the highly pathogenic avian influenza A subtype H5N1 virus outbreaks over space and time in poultry from 2007 to 2009 in Bangladesh, we applied descriptive and analytical spatial statistics. Temporal distribution of the outbreaks revealed three independent waves of outbreaks that were clustered during winter and spring. The descriptive analyses revealed that the magnitude of the second wave was the highest as compared to the first and third waves. Exploratory mapping of the infected flocks revealed that the highest intensity and magnitude of the outbreaks was systematic and persistent in an oblique line that connects south-east to north-west through the central part of the country. The line follows the Brahmaputra-Meghna river system, the junction between Central Asian and East Asian flyways, and the major poultry trading route in Bangladesh. Moreover, several important migratory bird areas were identified along the line. Geostatistical analysis revealed significant latitudinal directions of outbreak progressions that have similarity to the detected line of intensity and magnitude. CONCLUSION/SIGNIFICANCE: The line of magnitude and direction indicate the necessity of mobilizing maximum resources on this line to strengthen the existing surveillance.

  19. Preventable H5N1 avian influenza epidemics in the British poultry industry network exhibit characteristic scales.

    Science.gov (United States)

    Jonkers, A R T; Sharkey, K J; Christley, R M

    2010-04-01

    Epidemics are frequently simulated on redundantly wired contact networks, which have many more links between sites than are minimally required to connect all. Consequently, the modelled pathogen can travel numerous alternative routes, complicating effective containment strategies. These networks have moreover been found to exhibit 'scale-free' properties and percolation, suggesting resilience to damage. However, realistic H5N1 avian influenza transmission probabilities and containment strategies, here modelled on the British poultry industry network, show that infection dynamics can additionally express characteristic scales. These system-preferred scales constitute small areas within an observed power law distribution that exhibit a lesser slope than the power law itself, indicating a slightly increased relative likelihood. These characteristic scales are here produced by a network-pervading intranet of so-called hotspot sites that propagate large epidemics below the percolation threshold. This intranet is, however, extremely vulnerable; targeted inoculation of a mere 3-6% (depending on incorporated biosecurity measures) of the British poultry industry network prevents large and moderate H5N1 outbreaks completely, offering an order of magnitude improvement over previously advocated strategies affecting the most highly connected 'hub' sites. In other words, hotspots and hubs are separate functional entities that do not necessarily coincide, and hotspots can make more effective inoculation targets. Given the ubiquity and relevance of networks (epidemics, Internet, power grids, protein interaction), recognition of this spreading regime elsewhere would suggest a similar disproportionate sensitivity to such surgical interventions. PMID:19828507

  20. 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.

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

    Directory of Open Access Journals (Sweden)

    Tham Chi Dung

    2014-11-01

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

  2. 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

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

    International Nuclear Information System (INIS)

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

  4. 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.

  5. Intranasal Flu Vaccine Protective against Seasonal and H5N1 Avian Influenza Infections

    OpenAIRE

    Alsharifi, Mohammed; Furuya, Yoichi; Bowden, Timothy R.; Lobigs, Mario; Koskinen, Aulikki; Regner, Matthias; Trinidad, Lee; Boyle, David B.; Müllbacher, Arno

    2009-01-01

    Background Influenza A (flu) virus causes significant morbidity and mortality worldwide, and current vaccines require annual updating to protect against the rapidly arising antigenic variations due to antigenic shift and drift. In fact, current subunit or split flu vaccines rely exclusively on antibody responses for protection and do not induce cytotoxic T (Tc) cell responses, which are broadly cross-reactive between virus strains. We have previously reported that γ-ray inactivated flu virus ...

  6. Intranasal Flu Vaccine Protective against Seasonal and H5N1 Avian Influenza Infections

    OpenAIRE

    Mohammed Alsharifi; Yoichi Furuya; Bowden, Timothy R.; Mario Lobigs; Aulikki Koskinen; Matthias Regner; Lee Trinidad; Boyle, David B.; Arno Müllbacher

    2009-01-01

    BACKGROUND: Influenza A (flu) virus causes significant morbidity and mortality worldwide, and current vaccines require annual updating to protect against the rapidly arising antigenic variations due to antigenic shift and drift. In fact, current subunit or split flu vaccines rely exclusively on antibody responses for protection and do not induce cytotoxic T (Tc) cell responses, which are broadly cross-reactive between virus strains. We have previously reported that gamma-ray inactivated flu v...

  7. Specific detection of H5N1 avian influenza A virus in field specimens by a one-step RT-PCR assay

    Directory of Open Access Journals (Sweden)

    Gupta Sanjay

    2006-03-01

    Full Text Available Abstract Background Continuous outbreaks of the highly pathogenic H5N1 avian influenza A in Asia has resulted in an urgent effort to improve current diagnostics to aid containment of the virus and lower the threat of a influenza pandemic. We report here the development of a PCR-based assay that is highly specific for the H5N1 avian influenza A virus. Methods A one-step reverse-transcription PCR assay was developed to detect the H5N1 avian influenza A virus. The specificity of the assay was shown by testing sub-types of influenza A virus and other viral and bacterial pathogens; and on field samples. Results Validation on 145 field specimens from Vietnam and Malaysia showed that the assay was specific without cross reactivity to a number of other infuenza strains as well as human respiratory related pathogens. Detection was 100% from allantoic fluid in H5N1 positive samples, suggesting it to be a reliable sampling source for accurate detection. Conclusion The assay developed from this study indicates that the primers are specific for the H5N1 influenza virus. As shown by the field tested results, this assay would be highly useful as a diagnostic tool to help identify and control influenza epidemics.

  8. Evidence for the Convergence Model: The Emergence of Highly Pathogenic Avian Influenza (H5N1 in Viet Nam.

    Directory of Open Access Journals (Sweden)

    Sumeet Saksena

    Full Text Available Building on a series of ground breaking reviews that first defined and drew attention to emerging infectious diseases (EID, the 'convergence model' was proposed to explain the multifactorial causality of disease emergence. The model broadly hypothesizes disease emergence is driven by the co-incidence of genetic, physical environmental, ecological, and social factors. We developed and tested a model of the emergence of highly pathogenic avian influenza (HPAI H5N1 based on suspected convergence factors that are mainly associated with land-use change. Building on previous geospatial statistical studies that identified natural and human risk factors associated with urbanization, we added new factors to test whether causal mechanisms and pathogenic landscapes could be more specifically identified. Our findings suggest that urbanization spatially combines risk factors to produce particular types of peri-urban landscapes with significantly higher HPAI H5N1 emergence risk. The work highlights that peri-urban areas of Viet Nam have higher levels of chicken densities, duck and geese flock size diversities, and fraction of land under rice or aquaculture than rural and urban areas. We also found that land-use diversity, a surrogate measure for potential mixing of host populations and other factors that likely influence viral transmission, significantly improves the model's predictability. Similarly, landscapes where intensive and extensive forms of poultry production overlap were found at greater risk. These results support the convergence hypothesis in general and demonstrate the potential to improve EID prevention and control by combing geospatial monitoring of these factors along with pathogen surveillance programs.

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

    Science.gov (United States)

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

    2014-01-01

    Ducks are important maintenance hosts for avian influenza, including H5N1 highly pathogenic avian influenza viruses. A previous study indicated that persistence of H5N1 viruses in ducks after the development of humoral immunity may drive viral evolution following immune selection. As H5N1 HPAI is endemic in Indonesia, this mechanism may be important in understanding H5N1 evolution in that region. To determine the capability of domestic ducks to maintain prolonged shedding of Indonesian clade 2.1 H5N1 virus, two groups of Pekin ducks were inoculated through the eyes, nostrils and oropharynx and viral shedding and transmission investigated. Inoculated ducks (n = 15), which were mostly asymptomatic, shed infectious virus from the oral route from 1 to 8 days post inoculation, and from the cloacal route from 2-8 dpi. Viral ribonucleic acid was detected from 1-15 days post inoculation from the oral route and 1-24 days post inoculation from the cloacal route (cycle threshold Indonesian clade 2.1 H5N1 highly pathogenic avian influenza virus does not persist in individual ducks after acute infection.

  10. 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.

  11. First introduction of highly pathogenic H5N1 avian influenza A viruses in wild and domestic birds in Denmark, Northern Europe

    Directory of Open Access Journals (Sweden)

    Kabell Susanne

    2007-05-01

    Full Text Available Abstract Background Since 2005 highly pathogenic (HP avian influenza A H5N1 viruses have spread from Asia to Africa and Europe infecting poultry, humans and wild birds. HP H5N1 virus was isolated in Denmark for the first time in March 2006. A total of 44 wild birds were found positive for the HP H5N1 infection. In addition, one case was reported in a backyard poultry flock. Results Full-genome characterisation of nine isolates revealed that the Danish H5N1 viruses were highly similar to German H5N1 isolates in all genes from the same time period. The haemagglutinin gene grouped phylogenetically in H5 clade 2 subclade 2 and closest relatives besides the German isolates were isolates from Croatia in 2005, Nigeria and Niger in 2006 and isolates from Astrakhan in Russia 2006. The German and Danish isolates shared unique substitutions in the NA, PB1 and NS2 proteins. Conclusion The first case of HP H5N1 infection of wild and domestic birds in Denmark was experienced in March 2006. This is the first full genome characterisation of HP H5N1 avian influenza A virus in the Nordic countries. The Danish viruses from this time period have their origin from the wild bird strains from Qinghai in 2005. These viruses may have been introduced to the Northern Europe through unusual migration due to the cold weather in Eastern Europe at that time.

  12. Potential infections of H5N1 and H9N2 avian influenza do exist in Guangdong populations of China

    Institute of Scientific and Technical Information of China (English)

    LU Ci-yong; LU Jia-hai; CHEN Wei-qing; JIANG Li-fang; TAN Bing-yan; LING Wen-hua; ZHENG Bo-jian; SUI Hong-yan

    2008-01-01

    Background Southeast China is one of the sites of influenza origin. During 2003-2004, nine avian influenza outbreaks took place in Guangdong Province. But no human case was reported. To examine the status of potential human infection by human influenza (H1N1, H3N2) and avian influenza (H5N1, H7N7, H9N2) in the avian influenza epidemic area of Guangdong Province, China, we conducted a seroepidemiologic survey in the people of this area from April to June of 2004.Methods Three out of 9 H5N1 avian influenza affected poultry areas in Guangdong were randomly selected, and the population living within 3 kilometers of the affected poultries were chosen as the survey subjects. One thousand two hundred and fourteen people were selected from 3 villages at random. Human and avian influenza antibody tilers were determined by hemagglutination-inhibition (HI) test and microneutralization test (MNT).Results The positive rate of antibody to H5N1 was 3.03% in the occupational exposure group and 2.34% in general citizens group; that of H9N2 was 9.52% in the occupational exposure group and 3.76% in the general citizens group. Moreover one case in the occupational exposure group was positive for H7N7. One year later, all previously positive cases had become negative except for one H5N1 -positive case.Conclusion The observations imply that H5N1 and H9N2 avian influenza silent infections exist in Guangdon gpopulations.

  13. Vaccine Protection of Turkeys Against H5N1 Highly Pathogenic Avian Influenza Virus with a Recombinant Turkey Herpesvirus Expressing the Hemagglutinin Gene of Avian Influenza.

    Science.gov (United States)

    Kapczynski, Darrell R; Dorsey, Kristi; Chrzastek, Klaudia; Moraes, Mauro; Jackwood, Mark; Hilt, Debra; Gardin, Yannick

    2016-06-01

    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 by subtype and virulence of field virus. In this study, the efficacy of a recombinant turkey herpesvirus (rHVT) vector vaccine expressing the hemagglutinin gene from a clade 2.2 AI virus (A/Swan/Hungary/4999/2006) was evaluated in turkeys for protection against challenge with A/Whooper Swan/Mongolia/L244/2005 H5N1 HPAI clade 2.2. One-day-old turkeys received a single vaccination and were challenged at 4 wk postvaccination with 2 × 10(6) 50% embryo infectious dose per bird. The results demonstrate that following H5N1 HPAI challenge 96% protection was observed in rHVT-AI vaccinated turkeys. The oral and cloacal swabs taken from challenged birds demonstrated that vaccinated birds had lower incidence and titers of viral shedding compared with sham-vaccinated birds. From respiratory and gastrointestinal tracts, there was a greater than 6 log10 reduction in shedding in vaccinated birds as compared with the controls. This study provides support for the use of a commercially available rHVT-AI vaccine to protect turkeys against H5N1 HPAI. PMID:27309280

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

    Science.gov (United States)

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

    2016-01-01

    In Egypt, ducks kept for commercial purposes constitute the second highest poultry population, at 150 million ducks/year. Hence, ducks play an important role in the introduction and transmission of avian influenza (AI) in the Egyptian poultry population. Attempts to control outbreaks include the use of vaccines, which have varying levels of efficacy and failure. To date, the effects of vaccine efficacy has rarely been determined in ducks. In this study, we evaluated the protective efficacy of a live recombinant vector vaccine based on a turkey Herpes Virus (HVT) expressing the H5 gene from a clade 2.2 H5N1 HPAIV strain (A/Swan/Hungary/499/2006) (rHVT-H5) and a bivalent inactivated H5N1 vaccine prepared from clade 2.2.1 and 2.2.1.1 H5N1 seeds in Mulard ducks. A 0.3ml/dose subcutaneous injection of rHVT-H5 vaccine was administered to one-day-old ducklings (D1) and another 0.5ml/dose subcutaneous injection of the inactivated MEFLUVAC was administered at 7 days (D7). Four separate challenge experiments were conducted at Days 21, 28, 35 and 42, in which all the vaccinated ducks were challenged with 106EID50/duck of H5N1 HPAI virus (A/chicken/Egypt/128s/2012(H5N1) (clade 2.2.1) via intranasal inoculation. Maternal-derived antibody regression and post-vaccination antibody immune responses were monitored weekly. Ducks vaccinated at 21, 28, 35 and 42 days with the rHVT-H5 and MEFLUVAC vaccines were protected against mortality (80%, 80%, 90% and 90%) and (50%, 70%, 80% and 90%) respectively, against challenges with the H5N1 HPAI virus. The amount of viral shedding and shedding rates were lower in the rHVT-H5 vaccine groups than in the MEFLUVAC groups only in the first two challenge experiments. However, the non-vaccinated groups shed significantly more of the virus than the vaccinated groups. Both rHVT-H5 and MEFLUVAC provide early protection, and rHVT-H5 vaccine in particular provides protection against HPAI challenge. PMID:27304069

  15. Infectious and lethal doses of H5N1 highly pathogenic avian influenza virus for house sparrows (Passer domesticus) and rock pigeons (Columbia livia)

    Science.gov (United States)

    Terrestrial wild birds commonly associated with poultry farms have the potential to contribute to the spread of H5N1 highly pathogenic avian influenza virus within or between poultry facilities or between domesticated and wild bird populations. This potential, however, varies between species and is...

  16. Highly Pathogenic Avian Influenza Virus H5N1 Infection in a Long-Distance Migrant Shorebird under Migratory and Non-Migratory States

    NARCIS (Netherlands)

    Reperant, Leslie A.; Bildt, Marco W.G. van de; Amerongen, Geert van; Buehler, Deborah; Osterhaus, Albert D.M.E.; Jenni-Eiermann, Susi; Piersma, Theunis; Kuiken, Thijs

    2011-01-01

    Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The red knot (C

  17. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states

    NARCIS (Netherlands)

    L.A. Reperant (Leslie); M.W.G. van de Bildt (Marco); G. van Amerongen (Geert); D.M. Buehler (Debbie); A.D.M.E. Osterhaus (Albert); S. Jenni-Eiermann (Susi); T. Piersma (Theunis); T. Kuiken (Thijs)

    2011-01-01

    textabstractCorticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV) H5N1. The

  18. 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.

  19. Flying over an infected landscape: distribution of highly pathogenic avian influenza H5N1 risk in South Asia and satellite tracking of wild waterfowl

    Science.gov (United States)

    Gilbert, Marius; Newman, Scott H.; Takekawa, John Y.; Loth, Leo; Biradar, Chandrashekhar; Prosser, Diann J.; Balachandran, Sivananinthaperumal; Rao, Mandava Venkata Subba; Mundkur, Taej; Yan, Baoping; Xing, Zhi; Hou, Yuansheng; Batbayar, Nyambayar; Tseveenmayadag, Natsagdorj; Hogerwerf, Lenny; Slingenbergh, Jan; Xiao, Xiangming

    2010-01-01

    Highly pathogenic avian influenza (HPAI) H5N1 virus persists in Asia, posing a threat to poultry, wild birds, and humans. Previous work in Southeast Asia demonstrated that HPAI H5N1 risk is related to domestic ducks and people. Other studies discussed the role of migratory birds in the long distance spread of HPAI H5N1. However, the interplay between local persistence and long-distance dispersal has never been studied. We expand previous geospatial risk analysis to include South and Southeast Asia, and integrate the analysis with migration data of satellite-tracked wild waterfowl along the Central Asia flyway. We find that the population of domestic duck is the main factor delineating areas at risk of HPAI H5N1 spread in domestic poultry in South Asia, and that other risk factors, such as human population and chicken density, are associated with HPAI H5N1 risk within those areas. We also find that satellite tracked birds (Ruddy Shelduck and two Bar-headed Geese) reveal a direct spatio-temporal link between the HPAI H5N1 hot-spots identified in India and Bangladesh through our risk model, and the wild bird outbreaks in May,June,July 2009 in China(Qinghai Lake), Mongolia, and Russia. This suggests that the continental-scale dynamics of HPAI H5N1 are structured as a number of persistence areas delineated by domestic ducks, connected by rare transmission through migratory waterfowl.

  20. Penerapan Metode Diagnosis Cepat Virus Avian Influenza H5N1 dengan Metode Single Step Multiplex RT-PCR

    Directory of Open Access Journals (Sweden)

    Aris Haryanto

    2010-12-01

    Full Text Available Avian influenza (AI virus is a segmented single stranded (ss RNA virus with negative polarity andbelong to the Orthomyxoviridae family. Diagnose of AI virus can be performed using conventional methodsbut it has low sensitivity and specificity. The objective of the research was to apply rapid, precise, andaccurate diagnostic method for AI virus and also to determine its type and subtype based on the SingleStep Multiplex Reverse Transcriptase-Polymerase Chain Reaction targeting M, H5, and N1 genes. In thismethod M, H5 and NI genes were simultaneously amplified in one PCR tube. The steps of this researchconsist of collecting viral RNAs from 10 different AI samples originated from Maros Disease InvestigationCenter during 2007. DNA Amplification was conducted by Simplex RT-PCR using M primer set. Then, bysingle step multiplex RT-PCR were conducted simultaneously using M, H5 and N1 primers set. The RTPCRproducts were then separated on 1.5% agarose gel, stained by ethidum bromide and visualized underUV transilluminator. Results showed that 8 of 10 RNA virus samples could be amplified by Simplex RTPCRfor M gene which generating a DNA fragment of 276 bp. Amplification using multiplex RT-PCRmethod showed two of 10 samples were AI positive using multiplex RT-PCR, three DNA fragments weregenerated consisting of 276 bp for M gene, 189 bp for H5 gene, and 131 bp for N1. In this study, rapid andeffective diagnosis method for AI virus can be conducted by using simultaneous Single Step Multiplex RTPCR.By this technique type and subtype of AI virus, can also be determined, especially H5N1.

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

    Science.gov (United States)

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

    2011-01-01

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

  2. Hemagglutinin amino acids related to receptor specificity could affect the protection efficacy of H5N1 and H7N9 avian influenza virus vaccines in mice.

    Science.gov (United States)

    Xu, Lili; Bao, Linlin; Lau, Siu-Ying; Wu, Wai-Lan; Yuan, Jing; Gu, Songzhi; Li, Fengdi; Lv, Qi; Xu, Yanfeng; Pushko, Peter; Chen, Honglin; Qin, Chuan

    2016-05-17

    The continuous and sporadic human transmission of highly pathogenic avian H5N1 and H7N9 influenza viruses illustrates the urgent need for efficacious vaccines. However, all tested vaccines for the H5N1 and H7N9 viruses appear to be poorly immunogenic in mammals. In this study, a series of vaccines was produced using reverse genetic techniques that possess HA and NA genes from the H5N1 virus in the genetic background of the high-yield strain A/PR/8/34 (H1N1). Meanwhile, a group of H7N9 VLP vaccines that contain HA from H7N9 and NA and M1 from A/PR/8/34 (H1N1) was also produced. The HA amino acids of both the H5N1 and H7N9 vaccines differed at residues 226 and 228, both of which are critical for receptor specificity for an avian or mammalian host. Mice received two doses (3μg of HA each) of each vaccine and were challenged with lethal doses of wild type H5N1 or H7N9 viruses. The results showed that a recombinant H5N1 vaccine in which the HA amino acid G228 (avian specificity) was converted to S228 (mammalian specificity) resulted in higher HI titers, a lower viral titer in the lungs, and 100% protection in mice. However, a H7N9 VLP vaccine that contains L226 (mammalian specificity) and G228 (avian specificity) in HA showed better immunogenicity and protection efficacy in mice than VLP containing HA with either L226+S228 or Q226+S228. This observation indicated that specific HA residues could enhance a vaccine's protection efficacy and HA glycoproteins with both avian-type and human-type receptor specificities may produce better pandemic influenza vaccines for humans. PMID:27083426

  3. 一起水禽H5N1疫情暴发后人群感染风险评估%Risk assessment of H5N1 human infection after an outbreak of avian influenza in water fowl

    Institute of Scientific and Technical Information of China (English)

    王玉林; 王鸣; 刘于飞; 蒋力云; 柳洋; 杨智聪; 郝爱华; 伍业健; 李海麟; 李铁钢

    2009-01-01

    目的 评估动物禽流感疫情暴发后人群感染的风险,探讨禽流感传播的可能性.方法 采用现场流行病学调查、分子流行病学、血清学研究及应急监测方法 ,对病、死禽的所有密切接触者进行医学观察;采用红细胞凝集抑制实验、实时荧光逆转录-聚合酶链式反应(RT-PCR)、基因测序方法 ,检测全部密切接触者的血清抗体,采集4个疫点环境标本检测禽流感H5核酸.结果 检测4个疫点环境标本22份,H5核酸阳性1份,序列分析与广州市2006年人禽流感病毒株A/China/GD01/2006(H5N1)的同源性为95.9%;检测疫区及周边2个农贸市场活禽交易场所环境标本62份,H5核酸均阴性;采集密切接触者的血样68份、咽拭子68份,禽流感H9抗体阳性6份,H5抗体、H5核酸均阴性,医学观察7 d,未发现禽流感感染者;应急监测区报告流感样患者337例,经排查未发现可疑禽流感患者.结论 此起水禽H5N1暴发未造成扩散,也未出现人感染病例,表明此次疫情的禽流感病毒H5N1对人的传播能力尚不强,引起人群感染的风险较低.%Objective To evaluate the risk of human infection after the outbreak of avian influenza H5N1 in animals.and probe the possibility for virus transmission.Methods By means of field epidemiological study,molecular epidemiology,serology and emergency surveillance,persons who had ever closely contacted with sick or dead poultry were observed.While,the RT-PCR and gene sequencing method were used to detect H5 nucleic acid from environmental swabs from 4 epidemic spots,and hemagglutination inhibition assay was also used to detect H5 antibody.Results of 22 environmental swabs detected from 4 epidemic spots,one was positive for H5 nucleic acid,and the homogeneity was 95.9% as compared with H5N1 virus A/China,/GD01/2006 (H5N1) found in Guangzhou in 2006 by gene sequence analysis.62 environmental swabs from live poultry stalls of food markets near epidemic spot were detected

  4. siRNAs targeting PB2 and NP genes potentially inhibit replication of Highly Pathogenic H5N1 Avian Influenza Virus

    Indian Academy of Sciences (India)

    Padmanava Behera; Shanmugasundaram Nagarajan; Harshad V Murugkar; Semmannan Kalaiyarasu; Anil Prakash; Ragini Gothalwal; Shiv Chandra Dubey; Diwakar D Kulkarni; Chakradhar Tosh

    2015-06-01

    Highly Pathogenic Avian Influenza (HPAI) H5N1 virus is a threat to animal and public health worldwide. Till date, the H5N1 virus has claimed 402 human lives, with a mortality rate of 58% and has caused the death or culling of millions of poultry since 2003. In this study, we have designed three siRNAs (PB2-2235, PB2-479 and NP-865) targeting PB2 and NP genes of avian influenza virus and evaluated their potential, measured by hemagglutination (HA), plaque reduction and Real time RT-PCR assay, in inhibiting H5N1 virus (A/chicken/Navapur/7972/2006) replication in MDCK cells. The siRNAs caused 8- to 16-fold reduction in virus HA titers at 24 h after challenged with 100TCID50 of virus. Among these siRNAs, PB2-2235 offered the highest inhibition of virus replication with 16-fold reduction in virus HA titer, 80% reduction in viral plaque counts and 94% inhibition in expression of specific RNA at 24 h. The other two siRNAs had 68–73% and 87–88% reduction in viral plaque counts and RNA copy number, respectively. The effect of siRNA on H5N1 virus replication continued till 48h (maximum observation period). These findings suggest that PB2-2235 could efficiently inhibit HPAI H5N1 virus replication.

  5. DC-SIGN mediates avian H5N1 influenza virus infection in cis and in trans

    International Nuclear Information System (INIS)

    DC-SIGN, a C-type lectin receptor expressed in dendritic cells (DCs), has been identified as a receptor for human immunodeficiency virus type 1, hepatitis C virus, Ebola virus, cytomegalovirus, dengue virus, and the SARS coronavirus. We used H5N1 pseudotyped and reverse-genetics (RG) virus particles to study their ability to bind with DC-SIGN. Electronic microscopy and functional assay results indicate that pseudotyped viruses containing both HA and NA proteins express hemagglutination and are capable of infecting cells expressing α-2,3-linked sialic acid receptors. Results from a capture assay show that DC-SIGN-expressing cells (including B-THP-1/DC-SIGN and T-THP-1/DC-SIGN) and peripheral blood dendritic cells are capable of transferring H5N1 pseudotyped and RG virus particles to target cells; this action can be blocked by anti-DC-SIGN monoclonal antibodies. In summary, (a) DC-SIGN acts as a capture or attachment molecule for avian H5N1 virus, and (b) DC-SIGN mediates infections in cis and in trans

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    and immunohistochemistry staining of avian influenza viral antigens were recognized in the brain, pancreas and intestines of ducks and chickens. We identified ten human cases showing signs compatible with influenza-like illness; four were positive for influenza A/H3; however, none were positive for influenza A/H5...

  7. 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.

  8. Short-Term Heat Shock Affects Host–Virus Interaction in Mice Infected with Highly Pathogenic Avian Influenza Virus H5N1

    Science.gov (United States)

    Xue, Jia; Fan, Xiaoxu; Yu, Jing; Zhang, Shouping; Xiao, Jin; Hu, Yanxin; Wang, Ming

    2016-01-01

    Highly pathogenic avian influenza virus (HPAIV) H5N1 is a highly contagious virus that can cause acute respiratory infections and high human fatality ratio due to excessive inflammatory response. Short-term heat shock, as a stressful condition, could induce the expression of heat shock proteins that function as molecular chaperones to protect cells against multiple stresses. However, the protective effect of short-term heat shock in influenza infection is far from being understood. In this study, mice were treated at 39°C for 4 h before being infected with HPAIV H5N1. Interestingly, short-term heat shock significantly increased the levels of HSP70 and pro-inflammatory cytokines IL-6, TNF-α, IFN-β, and IFN-γ in the lung tissues of mice. Following HPAIV H5N1 infection, short-term heat shock alleviated immunopathology and viral replication in lung tissue and repressed the weight loss and increased the survival rate of H5N1-infected mice. Our data reported that short-term heat shock provided beneficial anti-HPAIV H5N1 properties in mice model, which offers an alternative strategy for non-drug prevention for influenza infection. PMID:27379054

  9. An immunoassay-based reverse-transcription loop-mediated isothermal amplification assay for the rapid detection of avian influenza H5N1 virus viremia.

    Science.gov (United States)

    Tang, Yi; Yu, Xu; Chen, Hao; Diao, Youxiang

    2016-12-15

    Avian influenza virus (AIV) subtype H5N1 attracts particular consideration because it is a continuous threat to animals and public health systems. The viremia caused by AIV H5N1 infection may increase the risk of blood-borne transmission between humans. Therefore, there is a need to rapidly evaluate and implement screening measures for AIV H5N1 viremia that allows for rapid response to this potentially pandemic threat. The present report describes an immunoassay-based reverse-transcription loop-mediated isothermal amplification (immuno-RT-LAMP) assay for the rapid detection of AIV H5N1 in whole blood samples. Using PCR tubes coated with an H5 subtype monoclonal antibody, AIV H5N1 virions were specifically captured from blood samples. After a thermal lysis step, the released viral N1 gene was exponentially amplified using RT-LAMP on either a real-time PCR instrument for quantitative analysis, or in a water bath system for endpoint analysis. The detection limit of the newly developed immuno-RT-LAMP assay was as low as 1.62×10(1) 50% embryo infectious dose/mL of virus in both regular samples and simulated viremia samples. There were no cross-reactions with non-H5N1 influenza viruses or other avian viruses. The reproducibility of the assay was confirmed using intra- and inter-assay tests with variability ranging from 1.05% to 3.37%. Our results indicate that immuno-RT-LAMP is a novel, effective point-of-care virus identification solution for the rapid diagnosis and monitoring of AIV H5N1 in blood samples. PMID:27376196

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

    Science.gov (United States)

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

    2016-01-01

    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. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration. PMID:27507581

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

    Science.gov (United States)

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

    2016-08-01

    The highly pathogenic avian influenza subtype H5N1 (HPAI H5N1) is a worldwide zoonotic infectious disease, threatening humans, poultry and wild birds. The role of wild birds in the spread of HPAI H5N1 has previously been investigated by comparing disease spread patterns with bird migration routes. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration.

  12. Rapid detection of avian influenza virus H5N1 in chicken tracheal samples using an impedance aptasensor with gold nanoparticles for signal amplification.

    Science.gov (United States)

    Karash, Sardar; Wang, Ronghui; Kelso, Lisa; Lu, Huaguang; Huang, Tony Jun; Li, Yanbin

    2016-10-01

    Highly pathogenic avian influenza virus H5N1 is a continuous threat to public health and poultry industry. The recurrence of the H5N1 led us to develop a robust, specific, and rapid detection method for the virus. In this study, an impedance aptasensor was developed for the virus detection using specific H5N1 aptamer and a gold interdigitated microelectrode. Streptavidin was immobilized on the microelectrode surface and biotin labeled H5N1 aptamer was bound to the immobilized streptavidin. The microelectrode was blocked with the polyethylene glycol and the bound aptamer captured the virus. The impedance change caused by the captured virus was measured using an impedance analyzer. To enhance impedance signal, a nanoparticle-based amplifier was designed and implemented by forming a network-like gold nanoparticles/H5N1-aptamer/thiocyanuric acid. The detection limit of the impedance aptasensor was 0.25 HAU for the pure virus and 1 HAU for the tracheal chicken swab samples spiked with the H5N1 virus. The detection time of aptasensor without employing the amplifier was less than an hour. The amplifier increased impedance by a 57-fold for the 1 HAU samples. Only negligible impedance change was observed for non-target viruses such as H5N2, H5N3, H7N2, H1N1, and H2N2. This aptasensor provides a foundation for the development of a portable aptasensor instrument. PMID:27452670

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

    Science.gov (United States)

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

    2016-01-01

    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. However, the different roles that the southward autumn and northward spring migration might play in virus transmission have hardly been explored. Using direction analysis, we analyze HPAI H5N1 transmission directions and angular concentration of currently circulating viral clades, and compare these with waterfowl seasonal migration directions along major waterfowl flyways. Out of 22 HPAI H5N1 transmission directions, 18 had both a southward direction and a relatively high concentration. Differences between disease transmission and waterfowl migration directions were significantly smaller for autumn than for spring migration. The four northward transmission directions were found along Asian flyways, where the initial epicenter of the virus was located. We suggest waterfowl first picked up the virus from East Asia, then brought it to the north via spring migration, and then spread it to other parts of world mainly by autumn migration. We emphasize waterfowl autumn migration plays a relatively important role in HPAI H5N1 transmission compared to spring migration.

  14. Quantitative assessment of a spatial multicriteria model for highly pathogenic avian influenza H5N1 in Thailand, and application in Cambodia.

    Science.gov (United States)

    Paul, Mathilde C; Goutard, Flavie L; Roulleau, Floriane; Holl, Davun; Thanapongtharm, Weerapong; Roger, François L; Tran, Annelise

    2016-01-01

    The Highly Pathogenic Avian Influenza H5N1 (HPAI) virus is now considered endemic in several Asian countries. In Cambodia, the virus has been circulating in the poultry population since 2004, with a dramatic effect on farmers' livelihoods and public health. In Thailand, surveillance and control are still important to prevent any new H5N1 incursion. Risk mapping can contribute effectively to disease surveillance and control systems, but is a very challenging task in the absence of reliable disease data. In this work, we used spatial multicriteria decision analysis (MCDA) to produce risk maps for HPAI H5N1 in poultry. We aimed to i) evaluate the performance of the MCDA approach to predict areas suitable for H5N1 based on a dataset from Thailand, comparing the predictive capacities of two sources of a priori knowledge (literature and experts), and ii) apply the best method to produce a risk map for H5N1 in poultry in Cambodia. Our results showed that the expert-based model had a very high predictive capacity in Thailand (AUC = 0.97). Applied in Cambodia, MCDA mapping made it possible to identify hotspots suitable for HPAI H5N1 in the Tonlé Sap watershed, around the cities of Battambang and Kampong Cham, and along the Vietnamese border. PMID:27489997

  15. A human antibody recognizing a conserved epitope of H5 hemagglutinin broadly neutralizes highly pathogenic avian influenza H5N1 viruses.

    Science.gov (United States)

    Hu, Hongxing; Voss, Jarrod; Zhang, Guoliang; Buchy, Philippi; Zuo, Teng; Wang, Lulan; Wang, Feng; Zhou, Fan; Wang, Guiqing; Tsai, Cheguo; Calder, Lesley; Gamblin, Steve J; Zhang, Linqi; Deubel, Vincent; Zhou, Boping; Skehel, John J; Zhou, Paul

    2012-03-01

    Influenza A virus infection is a persistent threat to public health worldwide due to its ability to evade immune surveillance through rapid genetic drift and shift. Current vaccines against influenza A virus provide immunity to viral isolates that are similar to vaccine strains. High-affinity neutralizing antibodies against conserved epitopes could provide immunity to diverse influenza virus strains and protection against future pandemic viruses. In this study, by using a highly sensitive H5N1 pseudotype-based neutralization assay to screen human monoclonal antibodies produced by memory B cells from an H5N1-infected individual and molecular cloning techniques, we developed three fully human monoclonal antibodies. Among them, antibody 65C6 exhibited potent neutralization activity against all H5 clades and subclades except for subclade 7.2 and prophylactic and therapeutic efficacy against highly pathogenic avian influenza H5N1 viruses in mice. Studies on hemagglutinin (HA)-antibody complexes by electron microscopy and epitope mapping indicate that antibody 65C6 binds to a conformational epitope comprising amino acid residues at positions 118, 121, 161, 164, and 167 (according to mature H5 numbering) on the tip of the membrane-distal globular domain of HA. Thus, we conclude that antibody 65C6 recognizes a neutralization epitope in the globular head of HA that is conserved among almost all divergent H5N1 influenza stains. PMID:22238297

  16. 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.

  17. Movements of wild ruddy shelducks in the Central Asian Flyway and their spatial relationship to outbreaks of highly pathogenic avian influenza H5N1

    Science.gov (United States)

    Takekawa, John Y.; Prosser, Diann J.; Collins, Bridget M.; Douglas, David C.; Perry, William M.; Baoping, Yan; Luo, Ze; Hou, Yuansheng; Lei, Fumin; Li, Tianxian; Li, Yongdong; Newman, Scott H.

    2013-01-01

    Highly pathogenic avian influenza H5N1 remains a serious concern for both poultry and human health. Wild waterfowl are considered to be the reservoir for low pathogenic avian influenza viruses; however, relatively little is known about their movement ecology in regions where HPAI H5N1 outbreaks regularly occur. We studied movements of the ruddy shelduck (Tadorna ferruginea), a wild migratory waterfowl species that was infected in the 2005 Qinghai Lake outbreak. We defined their migration with Brownian Bridge utilization distribution models and their breeding and wintering grounds with fixed kernel home ranges. We correlated their movements with HPAI H5N1 outbreaks, poultry density, land cover, and latitude in the Central Asian Flyway. Our Akaike Information Criterion analysis indicated that outbreaks were correlated with land cover, latitude, and poultry density. Although shelduck movements were included in the top two models, they were not a top parameter selected in AICc stepwise regression results. However, timing of outbreaks suggested that outbreaks in the flyway began during the winter in poultry with spillover to wild birds during the spring migration. Thus, studies of the movement ecology of wild birds in areas with persistent HPAI H5N1 outbreaks may contribute to understanding their role in transmission of this disease.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2013-04-22

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

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

    International Nuclear Information System (INIS)

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

  20. First detection of highly pathogenic avian influenza virus H5N1 in common kestrel falcon (Falco tinnunculus) in Egypt

    OpenAIRE

    ElBakrey, Reham M.; Mansour, Shimaa M. G.; Ali, Haytham; Knudsen, David E. B.; Eid, Amal A. M.

    2016-01-01

    Highly pathogenic avian influenza virus (HPAIV) poses threats to animal and human health worldwide. A common kestrel (Falco tinnunculus) was submitted to Avian and Rabbit Medicine Department, Zagazig University, Egypt. It exhibited torticollis, incoordination, and inability to stand. Conjunctivitis and crust formation were seen. Postmortem findings revealed congestion in internal organs and greenish content in gizzard. No avian pox virus was detected in cutaneous lesions neither in histopatho...

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

    International Nuclear Information System (INIS)

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

  2. Recombinant trimeric HA protein immunogenicity of H5N1 avian influenza viruses and their combined use with inactivated or adenovirus vaccines.

    Directory of Open Access Journals (Sweden)

    Shih-Chang Lin

    Full Text Available BACKGROUND: The highly pathogenic avian influenza (HPAI H5N1 virus continues to cause disease in poultry and humans. The hemagglutinin (HA envelope protein is the primary target for subunit vaccine development. METHODOLOGY/PRINCIPAL FINDINGS: We used baculovirus-insect cell expression to obtain trimeric recombinant HA (rHA proteins from two HPAI H5N1 viruses. We investigated trimeric rHA protein immunogenicity in mice via immunizations, and found that the highest levels of neutralizing antibodies resulted from coupling with a PELC/CpG adjuvant. We also found that the combined use of trimeric rHA proteins with (a an inactivated H5N1 vaccine virus, or (b a recombinant adenovirus encoding full-length HA sequences for prime-boost immunization, further improved antibody responses against homologous and heterologous H5N1 virus strains. Data from cross-clade prime-boost immunization regimens indicate that sequential immunization with different clade HA antigens increased antibody responses in terms of total IgG level and neutralizing antibody titers. CONCLUSION/SIGNIFICANCE: Our findings suggest that the use of trimeric rHA in prime-boost vaccine regimens represents an alternative strategy for recombinant H5N1 vaccine development.

  3. Experimental infection of a North American raptor, American Kestrel (Falco sparverius, with highly pathogenic avian influenza virus (H5N1.

    Directory of Open Access Journals (Sweden)

    Jeffrey S Hall

    Full Text Available Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV subtype H5N1. Should HPAIV (H5N1 reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1 infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1. All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1 is introduced into North America.

  4. Experimental infection of a North American raptor, American kestrel (Falco sparverius), with highly pathogenic avian influenza virus (H5N1)

    Science.gov (United States)

    Hall, J.S.; Ip, H.S.; Franson, J.C.; Meteyer, C.; Nashold, S.; Teslaa, J.L.; French, J.; Redig, P.; Brand, C.

    2009-01-01

    Several species of wild raptors have been found in Eurasia infected with highly pathogenic avian influenza virus (HPAIV) subtype H5N1. Should HPAIV (H5N1) reach North America in migratory birds, species of raptors are at risk not only from environmental exposure, but also from consuming infected birds and carcasses. In this study we used American kestrels as a representative species of a North American raptor to examine the effects of HPAIV (H5N1) infection in terms of dose response, viral shedding, pathology, and survival. Our data showed that kestrels are highly susceptible to HPAIV (H5N1). All birds typically died or were euthanized due to severe neurologic disease within 4-5 days of inoculation and shed significant amounts of virus both orally and cloacally, regardless of dose administered. The most consistent microscopic lesions were necrosis in the brain and pancreas. This is the first experimental study of HPAIV infection in a North American raptor and highlights the potential risks to birds of prey if HPAIV (H5N1) is introduced into North America.

  5. The Use of Spatial and Spatiotemporal Modeling for Surveillance of H5N1 Highly Pathogenic Avian Influenza in Poultry in the Middle East.

    Science.gov (United States)

    Alkhamis, Mohammad; Hijmans, Robert J; Al-Enezi, Abdullah; Martínez-López, Beatriz; Perea, Andres M

    2016-05-01

    Since 2005, H5N1 highly pathogenic avian influenza virus (HPAIV) has severely impacted the economy and public health in the Middle East (ME) with Egypt as the most affected country. Understanding the high-risk areas and spatiotemporal distribution of the H5N1 HPAIV in poultry is prerequisite for establishing risk-based surveillance activities at a regional level in the ME. Here, we aimed to predict the geographic range of H5N1 HPAIV outbreaks in poultry in the ME using a set of environmental variables and to investigate the spatiotemporal clustering of outbreaks in the region. Data from the ME for the period 2005-14 were analyzed using maximum entropy ecological niche modeling and the permutation model of the scan statistics. The predicted range of high-risk areas (P > 0.60) for H5N1 HPAIV in poultry included parts of the ME northeastern countries, whereas the Egyptian Nile delta and valley were estimated to be the most suitable locations for occurrence of H5N1 HPAIV outbreaks. The most important environmental predictor that contributed to risk for H5N1 HPAIV was the precipitation of the warmest quarter (47.2%), followed by the type of global livestock production system (18.1%). Most significant spatiotemporal clusters (P Egypt, Turkey, Kuwait, Saudi Arabia, and Sudan. Results suggest that more information related to poultry holding demographics is needed to further improve prediction of risk for H5N1 HPAIV in the ME, whereas the methodology presented here may be useful in guiding the design of surveillance programs and in identifying areas in which underreporting may have occurred. PMID:27309050

  6. 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.

  7. The Use of Spatial and Spatiotemporal Modeling for Surveillance of H5N1 Highly Pathogenic Avian Influenza in Poultry in the Middle East.

    Science.gov (United States)

    Alkhamis, Mohammad; Hijmans, Robert J; Al-Enezi, Abdullah; Martínez-López, Beatriz; Perea, Andres M

    2016-05-01

    Since 2005, H5N1 highly pathogenic avian influenza virus (HPAIV) has severely impacted the economy and public health in the Middle East (ME) with Egypt as the most affected country. Understanding the high-risk areas and spatiotemporal distribution of the H5N1 HPAIV in poultry is prerequisite for establishing risk-based surveillance activities at a regional level in the ME. Here, we aimed to predict the geographic range of H5N1 HPAIV outbreaks in poultry in the ME using a set of environmental variables and to investigate the spatiotemporal clustering of outbreaks in the region. Data from the ME for the period 2005-14 were analyzed using maximum entropy ecological niche modeling and the permutation model of the scan statistics. The predicted range of high-risk areas (P > 0.60) for H5N1 HPAIV in poultry included parts of the ME northeastern countries, whereas the Egyptian Nile delta and valley were estimated to be the most suitable locations for occurrence of H5N1 HPAIV outbreaks. The most important environmental predictor that contributed to risk for H5N1 HPAIV was the precipitation of the warmest quarter (47.2%), followed by the type of global livestock production system (18.1%). Most significant spatiotemporal clusters (P < 0.001) were detected in Egypt, Turkey, Kuwait, Saudi Arabia, and Sudan. Results suggest that more information related to poultry holding demographics is needed to further improve prediction of risk for H5N1 HPAIV in the ME, whereas the methodology presented here may be useful in guiding the design of surveillance programs and in identifying areas in which underreporting may have occurred.

  8. An impedance immunosensor based on low-cost microelectrodes and specific monoclonal antibodies for rapid detection of avian influenza virus H5N1 in chicken swabs.

    Science.gov (United States)

    Lin, Jianhan; Wang, Ronghui; Jiao, Peirong; Li, Yuntao; Li, Yanbin; Liao, Min; Yu, Yude; Wang, Maohua

    2015-05-15

    Early screening of suspected cases is the key to control the spread of avian influenza (AI) H5N1. In our previous studies, an impedance biosensor with an interdigitated array microelectrode based biochip was developed and validated with pure AI H5 virus, but had limitations in cost and reliability of the biochip, specificity of the antibody against Asian in-field H5N1 virus and detection of H5N1 virus in real samples. The purpose of this study is to develop a low-cost impedance immunosensor for rapid detection of Asian in-field AI H5N1 virus in chicken swabs within 1h and validate it with the H5N1 virus. Specific monoclonal antibodies against AI H5N1 virus were developed by fusion of mouse myeloma cells with spleen cells isolated from an H5N1-virus-immunized mouse. Dot-ELISA analysis demonstrated that the developed antibodies had good affinity and specificity with the H5N1 virus. The microelectrodes were redesigned with compact size, fabricated using an improved wet-etching micro-fabrication process with a higher qualified production rate of 70-80%, and modified with the antibodies by the Protein A method. Equivalent circuit analysis indicated that electron transfer resistor was effective with the increase in impedance after capturing of the H5N1 viruses. Linear relationship between impedance change and logarithmic value of H5N1 virus at the concentrations from 2(-1) to 2(4) HAU/50 μl was found and the lower limit of detection was 2(-1) HAU/50 μl. No obvious interferences from non-target viruses such as H6N2, H9N2, Newcastle disease virus, and infectious bronchitis virus were found. Chicken swab tests showed that the impedance immunosensor had a comparable accuracy with real-time RT-PCR compared to viral isolation. PMID:25263315

  9. Modified H5 real-time reverse transcriptase-PCR oligonucleotides for detection of divergent avian influenza H5N1 viruses in Egypt.

    Science.gov (United States)

    Abdelwhab, E M; Abdelwhab, El-Sayed M; Arafa, Abdel-Satar; Erfan, Ahmed M; Aly, Mona M; Hafez, Hafez M

    2010-12-01

    The efforts exerted to prevent circulation of highly pathogenic avian influenza (HPAI) H5N1 virus in birds are the best way to prevent the emergence of a new virus subtype with pandemic potential. Despite the blanket vaccination strategy against HPAI H5N1 in Egypt, continuous circulation of the virus in poultry has increased since late 2007 as a result of the presence of genetic and antigenic distinct variant strains that have escaped during the immune response of vaccinated birds. Although the suspected poultry flocks have had signs and lesions commonly seen in HPAI H5N1-infected birds, escape of variant strains from detection by real-time reverse transcriptase-PCR (RRT-PCR) was observed. Sequence analysis of these variants revealed multiple single nucleotide substitutions in the primers and probe target sequences of the H5 gene by real-time RT-PCR. This study describes the results of RRT-PCR, modified from an existing protocol with regard to the detection of the partial H5 gene segment of the Egyptian H5N1 divergent viruses and applied to nationwide surveillance. The modified RRT-PCR assay was more sensitive than the original one in the detection of Egyptian isolates, with 104% amplification efficiency. Sixty-one field samples were found to be positive in our assay, but only 51 samples tested positive by the original protocol and were more sensitive than matrix gene RRT-PCR detection assay. A detection limit of 10 mean embryo infective dose (EID50) with the updated oligonucleotides primers and probe set was found. For the foreseeable future, mutation of H5N1 viruses and the endemic situation in developing countries require continuous improvement of current diagnostics to aid in the containment of the H5N1 virus in poultry sectors and to lower the threat of influenza virus spread. PMID:21313854

  10. Highly pathogenic avian influenza virus subtype H5N1 in Africa: a comprehensive phylogenetic analysis and molecular characterization of isolates.

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    Giovanni Cattoli

    Full Text Available Highly pathogenic avian influenza virus A/H5N1 was first officially reported in Africa in early 2006. Since the first outbreak in Nigeria, this virus spread rapidly to other African countries. From its emergence to early 2008, 11 African countries experienced A/H5N1 outbreaks in poultry and human cases were also reported in three of these countries. At present, little is known of the epidemiology and molecular evolution of A/H5N1 viruses in Africa. We have generated 494 full gene sequences from 67 African isolates and applied molecular analysis tools to a total of 1,152 A/H5N1 sequences obtained from viruses isolated in Africa, Europe and the Middle East between 2006 and early 2008. Detailed phylogenetic analyses of the 8 gene viral segments confirmed that 3 distinct sublineages were introduced, which have persisted and spread across the continent over this 2-year period. Additionally, our molecular epidemiological studies highlighted the association between genetic clustering and area of origin in a majority of cases. Molecular signatures unique to strains isolated in selected areas also gave us a clearer picture of the spread of A/H5N1 viruses across the continent. Mutations described as typical of human influenza viruses in the genes coding for internal proteins or associated with host adaptation and increased resistance to antiviral drugs have also been detected in the genes coding for transmembrane proteins. These findings raise concern for the possible human health risk presented by viruses with these genetic properties and highlight the need for increased efforts to monitor the evolution of A/H5N1 viruses across the African continent. They further stress how imperative it is to implement sustainable control strategies to improve animal and public health at a global level.

  11. 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.

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

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    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

  13. Histopathologic study of avian influenza H5N1 infection in humans%人感染高致病性禽流感病毒H5N1的病理学观察

    Institute of Scientific and Technical Information of China (English)

    陆敏; 谢志刚; 高占成; 王辰; 李宁; 李敏; 邵宏权; 王玉萍; 高子芬

    2008-01-01

    目的 观察人感染高致病性禽流感病毒H5N1后各主要脏器的病理改变.方法 按传染病尸体解剖要求对2例死亡病例系统解剖,并获得心、肝、脾、肺和肾等主要脏器,对1例重症患者行肺大泡切除术,组织常规HE和免疫组织化学染色,光学显微镜下观察.结果 2例肺组织主要呈弥漫性肺泡损伤改变.早期呈渗出性改变,肺泡上皮坏死脱落,肺泡腔内见大量均匀粉染渗出液伴广泛透明膜形成.中晚期主要呈增生性和纤维化性改变,肺泡上皮和支气管上皮增生,肺泡腔内渗出物和肺间质纤维化.1例在慢性支气管扩张症基础上伴弥漫性肺泡损伤和肺间质纤维化.免疫器官改变:全身淋巴组织萎缩伴活跃的噬血现象.其他脏器病变:1例心脏有间质性心肌炎;1例肾脏有急性肾小管坏死;1例有脑水肿伴脑实质内神经细胞嗜酸性变,轴突肿胀,粗细不均.脑室旁见灶状坏死.1例孕妇胎盘内多灶状滋养叶细胞坏死伴营养不良性钙化,有急性坏死性蜕膜炎.胚胎肺脏有肺水肿和肺炎改变.结论 人感染高致病性禽流感病毒H5N1后首先出现呼吸系统症状,广泛弥漫性肺泡损伤致低氧血症是病理学基础,患者最终因多器官功能衰竭致呼吸、循环衰竭死亡.%Objective To identify histopathologic changes of major organs and to correlate clinical symptoms in patients infected by avian influenza H5N1.Methods Autopsy study was performed in two patients died of avian influenza H5N1 infection,following conventional protocols and strict safety procedures.Tissue samples from all major organs of two cases and lung samples of one case were collected and fixed in 4% formaldehyde.Histopathologic changes were evaluated by light microscope.Results Diffuse alveolar damage (DAD) of the lung was seen in both cases.Lesions at various stages of development were seen involving different areas of the lung.At the early stages,the lungs exhibited

  14. Satellite tracking on the flyways of brown-headed gulls and their potential role in the spread of highly pathogenic avian influenza H5N1 virus.

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    Parntep Ratanakorn

    Full Text Available Brown-headed gulls (Larus brunnicephalus, winter visitors of Thailand, were tracked by satellite telemetry during 2008-2011 for investigating their roles in the highly pathogenic avian influenza (HPAI H5N1 virus spread. Eight gulls negative for influenza virus infection were marked with solar-powered satellite platform transmitters at Bang Poo study site in Samut Prakarn province, Thailand; their movements were monitored by the Argos satellite tracking system, and locations were mapped. Five gulls completed their migratory cycles, which spanned 7 countries (China, Bangladesh, India, Myanmar, Thailand, Cambodia, and Vietnam affected by the HPAI H5N1 virus. Gulls migrated from their breeding grounds in China to stay overwinter in Thailand and Cambodia; while Bangladesh, India, Myanmar, and Vietnam were the places of stopovers during migration. Gulls traveled an average distance of about 2400 km between Thailand and China and spent 1-2 weeks on migration. Although AI surveillance among gulls was conducted at the study site, no AI virus was isolated and no H5N1 viral genome or specific antibody was detected in the 75 gulls tested, but 6.6% of blood samples were positive for pan-influenza A antibody. No AI outbreaks were reported in areas along flyways of gulls in Thailand during the study period. Distance and duration of migration, tolerability of the captive gulls to survive the HPAI H5N1 virus challenge and days at viral shedding after the virus challenging suggested that the Brown-headed gull could be a potential species for AI spread, especially among Southeast Asian countries, the epicenter of H5N1 AI outbreak.

  15. Eco-virological approach for assessing the role of wild birds in the spread of avian influenza H5N1 along the Central Asian Flyway.

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    Scott H Newman

    Full Text Available A unique pattern of highly pathogenic avian influenza (HPAI H5N1 outbreaks has emerged along the Central Asia Flyway, where infection of wild birds has been reported with steady frequency since 2005. We assessed the potential for two hosts of HPAI H5N1, the bar-headed goose (Anser indicus and ruddy shelduck (Tadorna tadorna, to act as agents for virus dispersal along this 'thoroughfare'. We used an eco-virological approach to compare the migration of 141 birds marked with GPS satellite transmitters during 2005-2010 with: 1 the spatio-temporal patterns of poultry and wild bird outbreaks of HPAI H5N1, and 2 the trajectory of the virus in the outbreak region based on phylogeographic mapping. We found that biweekly utilization distributions (UDs for 19.2% of bar-headed geese and 46.2% of ruddy shelduck were significantly associated with outbreaks. Ruddy shelduck showed highest correlation with poultry outbreaks owing to their wintering distribution in South Asia, where there is considerable opportunity for HPAI H5N1 spillover from poultry. Both species showed correlation with wild bird outbreaks during the spring migration, suggesting they may be involved in the northward movement of the virus. However, phylogeographic mapping of HPAI H5N1 clades 2.2 and 2.3 did not support dissemination of the virus in a northern direction along the migration corridor. In particular, two subclades (2.2.1 and 2.3.2 moved in a strictly southern direction in contrast to our spatio-temporal analysis of bird migration. Our attempt to reconcile the disciplines of wild bird ecology and HPAI H5N1 virology highlights prospects offered by both approaches as well as their limitations.

  16. Eco-virological approach for assessing the role of wild birds in the spread of avian influenza H5N1 along the central Asian flyway

    Science.gov (United States)

    Newman, Scott H.; Hill, Nichola J.; Spragens, Kyle A.; Janies, Daniel; Voronkin, Igor O.; Prosser, Diann J.; Yan, Baoping; Lei, Fumin; Batbayar, Nyambayar; Natsagdorj, Tseveenmyadag; Bishop, Charles M.; Butler, Patrick J.; Wikelski, Martin; Balachandran, Sivananinthaperumal; Mundkur, Taej; Douglas, David C.; Takekawa, John Y.

    2012-01-01

    A unique pattern of highly pathogenic avian influenza (HPAI) H5N1 outbreaks has emerged along the Central Asia Flyway, where infection of wild birds has been reported with steady frequency since 2005. We assessed the potential for two hosts of HPAI H5N1, the bar-headed goose (Anser indicus) and ruddy shelduck (Tadorna tadorna), to act as agents for virus dispersal along this ‘thoroughfare’. We used an eco-virological approach to compare the migration of 141 birds marked with GPS satellite transmitters during 2005–2010 with: 1) the spatio-temporal patterns of poultry and wild bird outbreaks of HPAI H5N1, and 2) the trajectory of the virus in the outbreak region based on phylogeographic mapping. We found that biweekly utilization distributions (UDs) for 19.2% of bar-headed geese and 46.2% of ruddy shelduck were significantly associated with outbreaks. Ruddy shelduck showed highest correlation with poultry outbreaks owing to their wintering distribution in South Asia, where there is considerable opportunity for HPAI H5N1 spillover from poultry. Both species showed correlation with wild bird outbreaks during the spring migration, suggesting they may be involved in the northward movement of the virus. However, phylogeographic mapping of HPAI H5N1 clades 2.2 and 2.3 did not support dissemination of the virus in a northern direction along the migration corridor. In particular, two subclades (2.2.1 and 2.3.2) moved in a strictly southern direction in contrast to our spatio-temporal analysis of bird migration. Our attempt to reconcile the disciplines of wild bird ecology and HPAI H5N1 virology highlights prospects offered by both approaches as well as their limitations.

  17. Quantified degree of poultry exposure differs for human cases of avian influenza H5N1 and H7N9.

    Science.gov (United States)

    Bethmont, A; Bui, C M; Gardner, L; Sarkar, S; Chughtai, A A; Macintyre, C R

    2016-09-01

    Preliminary evidence suggests that direct poultry contact may play a lesser role in transmission of avian influenza A(H7N9) than A(H5N1) to humans. To better understand differences in risk factors, we quantified the degree of poultry contact reported by H5N1 and H7N9 World Health Organization-confirmed cases. We used publicly available data to classify cases by their degree of poultry contact, including direct and indirect. To account for potential data limitations, we used two methods: (1) case population method in which all cases were classified using a range of sources; and (2) case subset method in which only cases with detailed contact information from published research literature were classified. In the case population, detailed exposure information was unavailable for a large proportion of cases (H5N1, 54%; H7N9, 86%). In the case subset, direct contact proportions were higher in H5N1 cases (70·3%) than H7N9 cases (40·0%) (χ 2 = 18·5, P < 0·001), and indirect contact proportions were higher in H7N9 cases (44·6%) than H5N1 cases (19·4%) (χ 2 = 15·5, P < 0·001). Together with emerging evidence, our descriptive analysis suggests direct poultry contact is a clearer risk factor for H5N1 than for H7N9, and that other risk factors should also be considered for H7N9. PMID:27267621

  18. NS1 gene truncations partially attenuate H5N1 highly pathogenic avian influenza viruses in chickens

    Science.gov (United States)

    The polybasic amino acid sequence in the hemagglutinin (HA) protein of H5 and H7 avian influenza (AI) viruses determines the high pathogenicity (HP) phenotype in chickens. The NS1 protein plays an important role in blocking the induction of antiviral defenses and other regulatory functions and thus...

  19. 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....

  20. 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.

  1. Reintroduction of H5N1 highly pathogenic avian influenza virus by migratory water birds, causing poultry outbreaks in the 2010-2011 winter season in Japan.

    Science.gov (United States)

    Sakoda, Yoshihiro; Ito, Hiroshi; Uchida, Yuko; Okamatsu, Masatoshi; Yamamoto, Naoki; Soda, Kosuke; Nomura, Naoki; Kuribayashi, Saya; Shichinohe, Shintaro; Sunden, Yuji; Umemura, Takashi; Usui, Tatsufumi; Ozaki, Hiroichi; Yamaguchi, Tsuyoshi; Murase, Toshiyuki; Ito, Toshihiro; Saito, Takehiko; Takada, Ayato; Kida, Hiroshi

    2012-03-01

    H5N1 highly pathogenic avian influenza virus (HPAIV) was reintroduced and caused outbreaks in chickens in the 2010-2011 winter season in Japan, which had been free from highly pathogenic avian influenza (HPAI) since 2007 when HPAI outbreaks occurred and were controlled. On 14 October 2010 at Lake Ohnuma, Wakkanai, the northernmost part of Hokkaido, Japan, H5N1 HPAIVs were isolated from faecal samples of ducks flying from their nesting lakes in Siberia. Since then, in Japan, H5N1 HPAIVs have been isolated from 63 wild birds in 17 prefectures and caused HPAI outbreaks in 24 chicken farms in nine prefectures by the end of March in 2011. Each of these isolates was genetically closely related to the HPAIV isolates at Lake Ohnuma, and those in China, Mongolia, Russia and Korea, belonging to genetic clade 2.3.2.1. In addition, these isolates were genetically classified into three groups, suggesting that the viruses were transmitted by migratory water birds through at least three different routes from their northern territory to Japan. These isolates were antigenic variants, which is consistent with selection in poultry under the immunological pressure induced by vaccination. To prevent the perpetuation of viruses in the lakes where water birds nest in summer in Siberia, prompt eradication of HPAIVs in poultry is urgently needed in Asian countries where HPAI has not been controlled.

  2. VARIATION OF NON-CODING REGION AND CODING REGION OF 5’-TERMINAL CRNA OF POLYMERASE BASIC 1 OF AVIAN INFLUENZA VIRUS SUBTYPE H5N1

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    Gusti Ayu Yuniati Kencana

    2009-03-01

    Full Text Available The sequence of the Non-Coding Region (NCR and Coding Region (CR of 5’-terminal cRNA of thepolymerase basic 1 (PB1 gene as a major factor for the species adaptation of avian influenza virussubtype H5N1 (AIV H5N1 has been analysed. The information could be a virological signal for theemergence of a new strain with pandemic potential. Total RNA from twenty six (26 avian influenzasubtype H5N1 isolates were amplified using reverse-transcriptase-polymerase chain reaction (RT-PCRwith a universal forward primer for influenza virus and specifically designed backward primers. Fifteen(15 PB1 gene fragments could be amplified. RT-PCR products were sequenced and analyzed using Mega4software. The length of NCR of PB1 gene was found to be 24 bases and mostly shows conserved sequence,with an exception of Dk/Badung/2006 isolate which has C-7T substitution. A/T composition of PB1 NCRwas 54,2%, while the Dk/Badung/2006 isolate was 58,3%. Species and geographical specificity could not befound in the genetic distance, the amino acid polymorphism, as well as the phylogenetic analysis of t

  3. First reported incursion of highly pathogenic notifiable avian influenza A H5N1 viruses from clade 2.3.2 into European poultry.

    Science.gov (United States)

    Reid, S M; Shell, W M; Barboi, G; Onita, I; Turcitu, M; Cioranu, R; Marinova-Petkova, A; Goujgoulova, G; Webby, R J; Webster, R G; Russell, C; Slomka, M J; Hanna, A; Banks, J; Alton, B; Barrass, L; Irvine, R M; Brown, I H

    2011-02-01

    This study reports the first incursion into European poultry of H5N1 highly pathogenic notifiable avian influenza A (HPNAI) viruses from clade 2.3.2 that affected domestic poultry and wild birds in Romania and Bulgaria, respectively. Previous occurrences in Europe of HPNAI H5N1 in these avian populations have involved exclusively viruses from clade 2.2. This represents the most westerly spread of clade 2.3.2 viruses, which have shown an apparently expanding range of geographical dispersal since mid-2009 following confirmation of infections in wild waterfowl species in Mongolia and Eastern Russia. During March 2010, AI infection was suspected at post-mortem examination of two hens from two backyard flocks in Tulcea Country, Romania. HPNAI of H5N1 subtype was confirmed by reverse transcription polymerase chain reaction (RT-PCR). A second outbreak was confirmed 2 weeks later by RT-PCR, affecting all hens from another flock located 55 km east of the first cluster. On the same day, an H5N1 HPNAI virus was detected from a pooled tissue sample collected from a dead Common Buzzard found on the Black Sea coast in Bulgaria. Detailed genetic characterization of the haemagglutinin gene revealed the cleavage site of the isolates to be consistent with viruses of high pathogenicity belonging to clade 2.3.2 of the contemporary Eurasian H5N1 lineage. Viruses from a clade other than 2.2 have apparently spread to wild birds, with potential maintenance and spread through such populations. Whilst the scale of threat posed by the apparent westward spread of the clade 2.3.2 viruses remains uncertain, ongoing vigilance for clinical signs of disease as part of existing passive surveillance frameworks for AI, and the prompt reporting of suspect cases in poultry is advised.

  4. Evaluating the Impact of Environmental Temperature on Global Highly Pathogenic Avian Influenza (HPAI H5N1 Outbreaks in Domestic Poultry

    Directory of Open Access Journals (Sweden)

    Zhijie Zhang

    2014-06-01

    Full Text Available The emergence and spread of highly pathogenic avian influenza (HPAI A virus subtype H5N1 in Asia, Europe and Africa has had an enormously socioeconomic impact and presents an important threat to human health because of its efficient animal-to-human transmission. Many factors contribute to the occurrence and transmission of HPAI H5N1 virus, but the role of environmental temperature remains poorly understood. Based on an approach of integrating a Bayesian Cox proportional hazards model and a Besag-York-Mollié (BYM model, we examined the specific impact of environmental temperature on HPAI H5N1 outbreaks in domestic poultry around the globe during the period from 1 December 2003 to 31 December 2009. The results showed that higher environmental temperature was a significant risk factor for earlier occurrence of HPAI H5N1 outbreaks in domestic poultry, especially for a temperature of 25 °C. Its impact varied with epidemic waves (EWs, and the magnitude of the impact tended to increase over EWs.

  5. Global epidemiology of avian influenza A H5N1 virus infection in humans, 1997-2015: a systematic review of individual case data.

    Science.gov (United States)

    Lai, Shengjie; Qin, Ying; Cowling, Benjamin J; Ren, Xiang; Wardrop, Nicola A; Gilbert, Marius; Tsang, Tim K; Wu, Peng; Feng, Luzhao; Jiang, Hui; Peng, Zhibin; Zheng, Jiandong; Liao, Qiaohong; Li, Sa; Horby, Peter W; Farrar, Jeremy J; Gao, George F; Tatem, Andrew J; Yu, Hongjie

    2016-07-01

    Avian influenza A H5N1 viruses have caused many, typically severe, human infections since the first human case was reported in 1997. However, no comprehensive epidemiological analysis of global human cases of H5N1 from 1997 to 2015 exists. Moreover, few studies have examined in detail the changing epidemiology of human H5N1 cases in Egypt, especially given the outbreaks since November, 2014, which have the highest number of cases ever reported worldwide in a similar period. Data on individual patients were collated from different sources using a systematic approach to describe the global epidemiology of 907 human H5N1 cases between May, 1997, and April, 2015. The number of affected countries rose between 2003 and 2008, with expansion from east and southeast Asia, then to west Asia and Africa. Most cases (67·2%) occurred from December to March, and the overall case-fatality risk was 483 (53·5%) of 903 cases which varied across geographical regions. Although the incidence in Egypt has increased dramatically since November, 2014, compared with the cases beforehand, there were no significant differences in the fatality risk, history of exposure to poultry, history of patient contact, and time from onset to hospital admission in the recent cases. PMID:27211899

  6. H5N1亚型禽流感病毒NS1蛋白研究进展%The research progress of H5N1 subtype avian influenza virus NS1 protein

    Institute of Scientific and Technical Information of China (English)

    李观强; 李国明; 张志珍

    2011-01-01

    @@ 禽流感(avian influenza ,AI) 为A型流感病毒(avian influenza virus ,AIV)引起的禽类流行性感冒.根据是否引起流感及症状的不同,通常将禽流感分为高致病性(highly pathogenic avian influenza,HPAI)、低致病性(low pathogenic avian influenza,LPAI) 和非致病性禽流感(no pathogenic avian influenza,NPAI).

  7. Evidence for differing evolutionary dynamics of A/H5N1 viruses among countries applying or not applying avian influenza vaccination in poultry.

    Science.gov (United States)

    Cattoli, Giovanni; Fusaro, Alice; Monne, Isabella; Coven, Fethiye; Joannis, Tony; El-Hamid, Hatem S Abd; Hussein, Aly Ahmed; Cornelius, Claire; Amarin, Nadim Mukhles; Mancin, Marzia; Holmes, Edward C; Capua, Ilaria

    2011-11-21

    Highly pathogenic avian influenza (HPAI) H5N1 (clade 2.2) was introduced into Egypt in early 2006. Despite the control measures taken, including mass vaccination of poultry, the virus rapidly spread among commercial and backyard flocks. Since the initial outbreaks, the virus in Egypt has evolved into a third order clade (clade 2.2.1) and diverged into antigenically and genetically distinct subclades. To better understand the dynamics of HPAI H5N1 evolution in countries that differ in vaccination policy, we undertook an in-depth analysis of those virus strains circulating in Egypt between 2006 and 2010, and compared countries where vaccination was adopted (Egypt and Indonesia) to those where it was not (Nigeria, Turkey and Thailand). This study incorporated 751 sequences (Egypt n=309, Indonesia n=149, Nigeria n=106, Turkey n=87, Thailand n=100) of the complete haemagglutinin (HA) open reading frame, the major antigenic determinant of influenza A virus. Our analysis revealed that two main Egyptian subclades (termed A and B) have co-circulated in domestic poultry since late 2007 and exhibit different profiles of positively selected codons and rates of nucleotide substitution. The mean evolutionary rate of subclade A H5N1 viruses was 4.07×10(-3) nucleotide substitutions per site, per year (HPD 95%, 3.23-4.91), whereas subclade B possessed a markedly higher substitution rate (8.87×10(-3); 95% HPD 7.0-10.72×10(-3)) and a stronger signature of positive selection. Although the direct association between H5N1 vaccination and virus evolution is difficult to establish, we found evidence for a difference in the evolutionary dynamics of H5N1 viruses among countries where vaccination was or was not adopted. In particular, both evolutionary rates and the number of positively selected sites were higher in virus populations circulating in countries applying avian influenza vaccination for H5N1, compared to viruses circulating in countries which had never used vaccination. We

  8. 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

  9. Duration of immunity following the administration of oil-based avian influenza H5N1 vaccine in layers

    OpenAIRE

    NISAR, Maryam; Rashid, Asif; Iqbal, Muhammad

    2011-01-01

    Avian influenza (AI) occurs worldwide and causes tremendous economic losses. The disease is characterised by respiratory signs, depression, and reduced food and water intake. In the present study, an oil-based vaccine created by using Montanide ISA 70 MVG, was prepared and the duration of immunity checked at different time intervals. For this purpose, the cumulative mean titre (CMT) was calculated after employing haemagglutination inhibition test in 50 pullets at day zero before vaccination a...

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

    Directory of Open Access Journals (Sweden)

    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

  11. Spatial modeling of wild bird risk factors to investigate highly pathogenic A(H5N1) avian influenza virus transmission

    Science.gov (United States)

    Prosser, Diann J.; Hungerford, Laura L.; Erwin, R. Michael; Ottinger, Mary Ann; Takekawa, John Y.; Newman, Scott H.; Xiao, Xianming; Ellis, Erie C.

    2016-01-01

    One of the longest-persisting avian influenza viruses in history, highly pathogenic avian influenza virus (HPAIV) A(H5N1), continues to evolve after 18 years, advancing the threat of a global pandemic. Wild waterfowl (family Anatidae), are reported as secondary transmitters of HPAIV, and primary reservoirs for low-pathogenic avian influenza viruses, yet spatial inputs for disease risk modeling for this group have been lacking. Using GIS and Monte Carlo simulations, we developed geospatial indices of waterfowl abundance at 1 and 30 km resolutions and for the breeding and wintering seasons for China, the epicenter of H5N1. Two spatial layers were developed: cumulative waterfowl abundance (WAB), a measure of predicted abundance across species, and cumulative abundance weighted by H5N1 prevalence (WPR), whereby abundance for each species was adjusted based on prevalence values then totaled across species. Spatial patterns of the model output differed between seasons, with higher WAB and WPR in the northern and western regions of China for the breeding season and in the southeast for the wintering season. Uncertainty measures indicated highest error in southeastern China for both WAB and WPR. We also explored the effect of resampling waterfowl layers from 1 km to 30 km resolution for multi-scale risk modeling. Results indicated low average difference (less than 0.16 and 0.01 standard deviations for WAB and WPR, respectively), with greatest differences in the north for the breeding season and southeast for the wintering season. This work provides the first geospatial models of waterfowl abundance available for China. The indices provide important inputs for modeling disease transmission risk at the interface of poultry and wild birds. These models are easily adaptable, have broad utility to both disease and conservation needs, and will be available to the scientific community for advanced modeling applications.

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

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    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.

  13. Host Cytokine Responses of Pigeons Infected with Highly Pathogenic Thai Avian Influenza Viruses of Subtype H5N1 Isolated from Wild Birds

    OpenAIRE

    Tsuyoshi Hayashi; Yasuaki Hiromoto; Kridsada Chaichoune; Tuangthong Patchimasiri; Warunya Chakritbudsabong; Natanan Prayoonwong; Natnapat Chaisilp; Witthawat Wiriyarat; Sujira Parchariyanon; Parntep Ratanakorn; Yuko Uchida; Takehiko Saito

    2011-01-01

    Highly pathogenic avian influenza virus (HPAIV) of the H5N1 subtype has been reported to infect pigeons asymptomatically or induce mild symptoms. However, host immune responses of pigeons inoculated with HPAIVs have not been well documented. To assess host responses of pigeons against HPAIV infection, we compared lethality, viral distribution and mRNA expression of immune related genes of pigeons infected with two HPAIVs (A/Pigeon/Thailand/VSMU-7-NPT/2004; Pigeon04 and A/Tree sparrow/Ratchabu...

  14. Study on Efficacy of Gamma Radiation on the Inactivation of Highly Pathogenic Avian Influenza Virus H5N1 (Thai isolate) in Chicken Meat and Chicken Feces

    International Nuclear Information System (INIS)

    A study on the efficacy of gamma radiation on the inactivation of a highly pathogenic avian influenza virus H5N1 subtype, Thai isolate was carried out. The virus was in the form frozen infected allantoic fluid frozen chicken meat and frozen chicken feces. The result indicated that 9 kilo grey of gamma radiation could completely inactivated 106.0 EID50/ml of AIV infected allantoic fluid and 22 kiel grey and 15 kilo grey of gamma radiation completely inactivate 106.0 EID50/10/ grams of chicken meat and 106.0 EID50/5 grams of chicken feces respectively.

  15. A one-parameter model for the spread of Avian Influenza A/H5N1

    International Nuclear Information System (INIS)

    Using a Lindblad dissipation dynamics [Lindblad G. On the generators of quantum dynamical semigroups. Commun Math Phys 1976;48:119-130 and see also Gorini V, Frigerio A, Verri M, Kossakowski A, Sudarshan ECG. Properties of quantum Markovian master equations. Rep Math Phys 1978;13:149-173; Alicki R, Messer J. Nonlinear quantum dynamical semigroups for many-body open systems. J Stat Phys 1983;32:299-312.] for biological rate equations we derive a one-component discrete dynamics for the spread of Avian Influenza. Numerical solutions of the difference equations are calculated and compared with measurement data.

  16. Pathogenicity of an H5N1 avian influenza virus isolated in Vietnam in 2012 and reliability of conjunctival samples for diagnosis of infection.

    Science.gov (United States)

    Bui, Vuong N; Dao, Tung D; Nguyen, Tham T H; Nguyen, Lien T; Bui, Anh N; Trinh, Dai Q; Pham, Nga T; Inui, Kenjiro; Runstadler, Jonathan; Ogawa, Haruko; Nguyen, Khong V; Imai, Kunitoshi

    2014-01-22

    The continued spread of highly pathogenic avian influenza virus (HPAIV) subtype H5N1 among poultry in Vietnam poses a potential threat to animals and public health. To evaluate the pathogenicity of a 2012 H5N1 HPAIV isolate and to assess the utility of conjunctival swabs for viral detection and isolation in surveillance, an experimental infection with HPAIV subtype H5N1 was carried out in domestic ducks. Ducks were infected with 10(7.2) TCID50 of A/duck/Vietnam/QB1207/2012 (H5N1), which was isolated from a moribund domestic duck. In the infected ducks, clinical signs of disease, including neurological disorder, were observed. Ducks started to die at 3 days-post-infection (dpi), and the study mortality reached 67%. Viruses were recovered from oropharyngeal and conjunctival swabs until 7 dpi and from cloacal swabs until 4 dpi. In the ducks that died or were sacrificed on 3, 5, or 6 dpi, viruses were recovered from lung, brain, heart, pancreas and intestine, among which the highest virus titers were in the lung, brain or heart. Results of virus titration were confirmed by real-time RT-PCR. Genetic and phylogenetic analysis of the HA gene revealed that the isolate belongs to clade 2.3.2.1 similarly to the H5N1 viruses isolated in Vietnam in 2012. The present study demonstrated that this recent HPAI H5N1 virus of clade 2.3.2.1 could replicate efficiently in the systemic organs, including the brain, and cause severe disease with neurological symptoms in domestic ducks. Therefore, this HPAI H5N1 virus seems to retain the neurotrophic feature and has further developed properties of shedding virus from the oropharynx and conjunctiva in addition to the cloaca, potentially posing a higher risk of virus spread through cross-contact and/or environmental transmission. Continued surveillance and diagnostic programs using conjunctival swabs in the field would further verify the apparent reliability of conjunctival samples for the detection of AIV.

  17. Pathogenicity of an H5N1 avian influenza virus isolated in Vietnam in 2012 and reliability of conjunctival samples for diagnosis of infection.

    Science.gov (United States)

    Bui, Vuong N; Dao, Tung D; Nguyen, Tham T H; Nguyen, Lien T; Bui, Anh N; Trinh, Dai Q; Pham, Nga T; Inui, Kenjiro; Runstadler, Jonathan; Ogawa, Haruko; Nguyen, Khong V; Imai, Kunitoshi

    2014-01-22

    The continued spread of highly pathogenic avian influenza virus (HPAIV) subtype H5N1 among poultry in Vietnam poses a potential threat to animals and public health. To evaluate the pathogenicity of a 2012 H5N1 HPAIV isolate and to assess the utility of conjunctival swabs for viral detection and isolation in surveillance, an experimental infection with HPAIV subtype H5N1 was carried out in domestic ducks. Ducks were infected with 10(7.2) TCID50 of A/duck/Vietnam/QB1207/2012 (H5N1), which was isolated from a moribund domestic duck. In the infected ducks, clinical signs of disease, including neurological disorder, were observed. Ducks started to die at 3 days-post-infection (dpi), and the study mortality reached 67%. Viruses were recovered from oropharyngeal and conjunctival swabs until 7 dpi and from cloacal swabs until 4 dpi. In the ducks that died or were sacrificed on 3, 5, or 6 dpi, viruses were recovered from lung, brain, heart, pancreas and intestine, among which the highest virus titers were in the lung, brain or heart. Results of virus titration were confirmed by real-time RT-PCR. Genetic and phylogenetic analysis of the HA gene revealed that the isolate belongs to clade 2.3.2.1 similarly to the H5N1 viruses isolated in Vietnam in 2012. The present study demonstrated that this recent HPAI H5N1 virus of clade 2.3.2.1 could replicate efficiently in the systemic organs, including the brain, and cause severe disease with neurological symptoms in domestic ducks. Therefore, this HPAI H5N1 virus seems to retain the neurotrophic feature and has further developed properties of shedding virus from the oropharynx and conjunctiva in addition to the cloaca, potentially posing a higher risk of virus spread through cross-contact and/or environmental transmission. Continued surveillance and diagnostic programs using conjunctival swabs in the field would further verify the apparent reliability of conjunctival samples for the detection of AIV. PMID:24211664

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

    Directory of Open Access Journals (Sweden)

    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.

  19. RNA interference of avian influenza virus H5N1 by directly inhibiting mRNA with siRNA expression plasmids

    International Nuclear Information System (INIS)

    Full text: Avian influenza virus H5N1 causes widespread infection in the birds and human respiratory tract, but existing vaccines and drug therapy are of limited value. Here we show that small interfering RNA (siRNA) specific for conserved regions of the viral genome can potently inhibit influenza virus production in cell lines, embryonated chicken eggs and BALB/c mice. SiRNA expression plasmid pBabe-Super was chosen in the study, which directed the synthesis of small interfering RNA in cells. The inhibition depended on the presence of a functional antisense strand in the small interfering RNA duplex, suggesting that viral mRNA is the target of RNA interference. Among three small interfering RNA expression plasmids we designed, we found that small interfering RNA for nucleocapsid protein (NP) had a specific effect in inhibiting the accumulation of RNA in infected cells because of a critical requirement for newly synthesized nucleocapsid proteins in avian influenza viral RNA transcription and replication. The findings reveal that newly synthesized nucleocapsid, polymerase A (PA) and polymerase B1 (PB1) proteins are required for avian influenza virus transcription and replication and provide a basis for the development of small interfering RNA as prophylaxis and therapy for avian influenza infection in birds and humans. (author)

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

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    Kateri Bertran

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

  1. Construction of recombinant baculoviruses expressing hemagglutinin of H5N1 avian influenza and research on the immunogenicity

    Science.gov (United States)

    Ge, Jingping; An, Qi; Gao, Dongni; Liu, Ying; Ping, Wenxiang

    2016-01-01

    Recombinant baculoviruses with different promoter and regulatory elements were constructed to enhance the expression of target protein and boost the efficacies of avian influenza vaccine. Hemagglutinin gene was cloned into the baculovirus transfer vectors driven by cytomegaloviru (CMV) and White spot syndrome virus immediate-early promoter one (WSSV ie1) promoter respectively, with different regulatory elements. The recombinant baculoviruses were directly used as vaccines to immunize specific pathogen-free chickens. The protein expression levels of recombinant baculoviruses BV-S-HA and BV-S-ITRs-HA were respectively 2.43 and 2.67 times than that of BV-S-con-HA, while the protein expression levels of BV-A-HA and BV-A-ITRs-HA were respectively 2.44 and 2.69 times than that of BV-S-con-HA. Immunoglobulin G (IgG) antibody levels induced by BV-A and BV-S series recombinant baculovirus were significantly higher than the commercialized vaccine group (P < 0.05). Among the groups with same promoter, the IgG antibody levels induced by the baculovirus containing regulatory elements were significantly higher than control group. Additionally, the immune effects induced by BV-A series recombinant baculoviruses with WSSV ie1 promoter were significantly stronger than the BV-S series recombinant baculoviruses with CMV promoter. The avian influenza vaccine prepared based on baculovirus vector can simultaneously stimulate the humoral and cellular immune responses. PMID:27063566

  2. Potential spread of highly pathogenic avian influenza H5N1 by wildfowl: dispersal ranges and rates determined from large-scale satellite telemetry

    Science.gov (United States)

    Gaidet, Nicolas; Cappelle, Julien; Takekawa, John Y.; Prosser, Diann J.; Iverson, Samuel A.; Douglas, David C.; Perry, William M.; Mundkur, Taej; Newman, Scott H.

    2010-01-01

    1. Migratory birds are major candidates for long-distance dispersal of zoonotic pathogens. In recent years, wildfowl have been suspected of contributing to the rapid geographic spread of the highly pathogenic avian influenza (HPAI) H5N1 virus. Experimental infection studies reveal that some wild ducks, geese and swans shed this virus asymptomatically and hence have the potential to spread it as they move. 2. We evaluate the dispersive potential of HPAI H5N1 viruses by wildfowl through an analysis of the movement range and movement rate of birds monitored by satellite telemetry in relation to the apparent asymptomatic infection duration (AID) measured in experimental studies. We analysed the first large-scale data set of wildfowl movements, including 228 birds from 19 species monitored by satellite telemetry in 2006–2009, over HPAI H5N1 affected regions of Asia, Europe and Africa. 3. Our results indicate that individual migratory wildfowl have the potential to disperse HPAI H5N1 over extensive distances, being able to perform movements of up to 2900 km within timeframes compatible with the duration of asymptomatic infection. 4. However, the likelihood of such virus dispersal over long distances by individual wildfowl is low: we estimate that for an individual migratory bird there are, on average, only 5–15 days per year when infection could result in the dispersal of HPAI H5N1 virus over 500 km. 5. Staging at stopover sites during migration is typically longer than the period of infection and viral shedding, preventing birds from dispersing a virus over several consecutive but interrupted long-distance movements. Intercontinental virus dispersion would therefore probably require relay transmission between a series of successively infected migratory birds. 6. Synthesis and applications. Our results provide a detailed quantitative assessment of the dispersive potential of HPAI H5N1 virus by selected migratory birds. Such dispersive potential rests on the

  3. 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.

  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

    Science.gov (United States)

    Beginning with Hong Kong in 2002, vaccines have been used as part of an integrated control strategy in 14 countries/regions to protect poultry against H5N1 high pathogenicity avian influenza (HPAI). H5N1 HPAI was first reported in Indonesia in 2003 and vaccination was initiated the following year. ...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    Abdullahi, Auwalu Yusuf; Kallon, Sanpha; Yu, Xingang; Zhang, Yongliang; Li, Guoqing

    2016-01-01

    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. PMID:27597953

  7. Susceptibility to and transmission of H5N1 and H7N1 highly pathogenic avian influenza viruses in bank voles (Myodes glareolus).

    Science.gov (United States)

    Romero Tejeda, Aurora; Aiello, Roberta; Salomoni, Angela; Berton, Valeria; Vascellari, Marta; Cattoli, Giovanni

    2015-01-01

    The study of influenza type A (IA) infections in wild mammals populations is a critical gap in our knowledge of how IA viruses evolve in novel hosts that could be in close contact with avian reservoir species and other wild animals. The aim of this study was to evaluate the susceptibility to infection, the nasal shedding and the transmissibility of the H7N1 and H5N1 highly pathogenic avian influenza (HPAI) viruses in the bank vole (Myodes glareolus), a wild rodent common throughout Europe and Asia. Two out of 24 H5N1-infected voles displayed evident respiratory distress, while H7N1-infected voles remained asymptomatic. Viable virus was isolated from nasal washes collected from animals infected with both HPAI viruses, and extra-pulmonary infection was confirmed in both experimental groups. Histopathological lesions were evident in the respiratory tract of infected animals, although immunohistochemistry positivity was only detected in lungs and trachea of two H7N1-infected voles. Both HPAI viruses were transmitted by direct contact, and seroconversion was confirmed in 50% and 12.5% of the asymptomatic sentinels in the H7N1 and H5N1 groups, respectively. Interestingly, viable virus was isolated from lungs and nasal washes collected from contact sentinels of both groups. The present study demonstrated that two non-rodent adapted HPAI viruses caused asymptomatic infection in bank voles, which shed high amounts of the viruses and were able to infect contact voles. Further investigations are needed to determine whether bank voles could be involved as silent hosts in the transmission of HPAI viruses to other mammals and domestic poultry. PMID:25963535

  8. Electrochemical detection of avian influenza virus H5N1 gene sequence using a DNA aptamer immobilized onto a hybrid nanomaterial-modified electrode

    International Nuclear Information System (INIS)

    Highlights: → A sensitive electrochemical biosensor for the detection of gene sequence was developed. → The biosensor was assembled by MWNT, polypyrrole nanowires and gold nanoparticles. → The hybrid nanomaterials could provide a porous structure with good properties. → The biosensor has highly selectivity and sensitivity. → The design strategy is expected to have extensive applications in other biosensors - Abstract: A sensitive electrochemical method for the detection of avian influenza virus (AIV) H5N1 gene sequence using a DNA aptamer immobilized onto a hybrid nanomaterial-modified electrode was developed. To enhance the selectivity and sensitivity, the modified electrode was assembled with multi-wall carbon nanotubes (MWNT), polypyrrole nanowires (PPNWs) and gold nanoparticles (GNPs). This electrode offered a porous structure with a large effective surface area, highly electrocatalytic activities and electronic conductivity. Therefore, the amount of DNA aptamer immobilized onto the electrode was increased while the accessibility of the detection target was maintained. The biosensor is based on the hybridization and preferred orientation of a DNA aptamer immobilized onto a modified electrode surface with its target (H5N1 specific sequence) present in solution. It is selective for the H5N1 specific sequence, and the signal of the indicator was approximately linear to log(concentration) of the H5N1 specific sequence from 5.0 x 10-12 to 1.0 x 10-9 M (R = 0.9863) with a detection limit of 4.3 x 10-13 M. These studies showed that the new hybrid nanomaterial (MWNT/PPNWs/GNPs) and the DNA aptamer could be used to fabricate an electrochemical biosensor for gene sequence detection. Furthermore, this design strategy is expected to have extensive applications in other biosensors.

  9. Electrochemical detection of avian influenza virus H5N1 gene sequence using a DNA aptamer immobilized onto a hybrid nanomaterial-modified electrode

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xianggang [College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong (China); Cheng Ziqiang, E-mail: czqsd@126.com [College of Animal Science and Technology, Shandong Agricultural University, Taian 271018, Shandong (China); Fan Hai [College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong (China); Ai Shiyun, E-mail: ashy@sdau.edu.cn [College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong (China); Han Ruixia [College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, Shandong (China)

    2011-07-15

    Highlights: > A sensitive electrochemical biosensor for the detection of gene sequence was developed. > The biosensor was assembled by MWNT, polypyrrole nanowires and gold nanoparticles. > The hybrid nanomaterials could provide a porous structure with good properties. > The biosensor has highly selectivity and sensitivity. > The design strategy is expected to have extensive applications in other biosensors - Abstract: A sensitive electrochemical method for the detection of avian influenza virus (AIV) H5N1 gene sequence using a DNA aptamer immobilized onto a hybrid nanomaterial-modified electrode was developed. To enhance the selectivity and sensitivity, the modified electrode was assembled with multi-wall carbon nanotubes (MWNT), polypyrrole nanowires (PPNWs) and gold nanoparticles (GNPs). This electrode offered a porous structure with a large effective surface area, highly electrocatalytic activities and electronic conductivity. Therefore, the amount of DNA aptamer immobilized onto the electrode was increased while the accessibility of the detection target was maintained. The biosensor is based on the hybridization and preferred orientation of a DNA aptamer immobilized onto a modified electrode surface with its target (H5N1 specific sequence) present in solution. It is selective for the H5N1 specific sequence, and the signal of the indicator was approximately linear to log(concentration) of the H5N1 specific sequence from 5.0 x 10{sup -12} to 1.0 x 10{sup -9} M (R = 0.9863) with a detection limit of 4.3 x 10{sup -13} M. These studies showed that the new hybrid nanomaterial (MWNT/PPNWs/GNPs) and the DNA aptamer could be used to fabricate an electrochemical biosensor for gene sequence detection. Furthermore, this design strategy is expected to have extensive applications in other biosensors.

  10. A molecular and antigenic survey of H5N1 highly pathogenic avian influenza virus isolates from smallholder duck farms in Central Java, Indonesia during 2007-2008

    Directory of Open Access Journals (Sweden)

    Junaidi Akhmad

    2011-09-01

    Full Text Available Abstract Background Indonesia is one of the countries most severely affected by H5N1 highly pathogenic avian influenza (HPAI virus in terms of poultry and human health. However, there is little information on the diversity of H5N1 viruses circulating in backyard farms, where chickens and ducks often intermingle. In this study, H5N1 virus infection occurring in 96 smallholder duck farms in central Java, Indonesia from 2007-2008 was investigated and the molecular and antigenic characteristics of H5N1 viruses isolated from these farms were analysed. Results All 84 characterised viruses belonged to H5N1 clade 2.1 with three virus sublineages being identified: clade 2.1.1 (1, clade 2.1.3 (80, and IDN/6/05-like viruses (3 that did not belong to any of the present clades. All three clades were found in ducks, while only clade 2.1.3 was isolated from chickens. There were no significant amino acid mutations of the hemagglutinin (HA and neuraminidase (NA sites of the viruses, including the receptor binding, glycosylation, antigenic and catalytic sites and NA inhibitor targets. All the viruses had polybasic amino acids at the HA cleavage site. No evidence of major antigenic variants was detected. Based on the HA gene, identical virus variants could be found on different farms across the study sites and multiple genetic variants could be isolated from HPAI outbreaks simultaneously or at different time points from single farms. HPAI virus was isolated from both ducks and chickens; however, the proportion of surviving duck cases was considerably higher than in chickens. Conclusions The 2.1.3 clade was the most common lineage found in this study. All the viruses had sequence characteristic of HPAI, but negligible variations in other recognized amino acids at the HA and NA proteins which determine virus phenotypes. Multiple genetic variants appeared to be circulating simultaneously within poultry communities. The high proportion of live duck cases compared to

  11. Post-exposure treatment with whole inactivated H5N1 avian influenza virus protects against lethal homologous virus infection in mice.

    Science.gov (United States)

    Hagan, Mable; Ranadheera, Charlene; Audet, Jonathan; Morin, Jocelyn; Leung, Anders; Kobasa, Darwyn

    2016-01-01

    Concerns with H5N1 influenza viruses include their prevalence in wild and domestic poultry, high mortality rate (~60%) in humans with some strains, lack of pre-existing immunity in humans, and the possibility that these viruses acquire mutations that enable efficient transmission between humans. H5 subtype viruses of Eurasian origin have recently appeared in wild and domestic bird populations in North America, and have led to the generation of new virus strains that are highly pathogenic in poultry. These new H5 HA containing viruses with their ability to evolve rapidly represent an unknown threat to humans in contact with infected poultry, and vaccination with an off-the-shelf vaccine may be impractical to provide protection to at-risk individuals. Instead, we have evaluated the efficacy of a formalin-inactivated vaccine, which could be derived directly from a circulating virus, to provide post-exposure protection. This strategy was evaluated using a prototypic highly pathogenic avian H5N1 strain, A/Vietnam/1203/2004, and demonstrated rapid induction of adaptive immune responses providing protection in a mammalian model of lethal infection. Additionally, this post-exposure vaccine was highly efficacious when administered 24 hours after exposure. This study offers a platform for developing effective post-exposure vaccines for treatment of highly virulent influenza infections. PMID:27405487

  12. Post-exposure treatment with whole inactivated H5N1 avian influenza virus protects against lethal homologous virus infection in mice

    Science.gov (United States)

    Hagan, Mable; Ranadheera, Charlene; Audet, Jonathan; Morin, Jocelyn; Leung, Anders; Kobasa, Darwyn

    2016-01-01

    Concerns with H5N1 influenza viruses include their prevalence in wild and domestic poultry, high mortality rate (~60%) in humans with some strains, lack of pre-existing immunity in humans, and the possibility that these viruses acquire mutations that enable efficient transmission between humans. H5 subtype viruses of Eurasian origin have recently appeared in wild and domestic bird populations in North America, and have led to the generation of new virus strains that are highly pathogenic in poultry. These new H5 HA containing viruses with their ability to evolve rapidly represent an unknown threat to humans in contact with infected poultry, and vaccination with an off-the-shelf vaccine may be impractical to provide protection to at-risk individuals. Instead, we have evaluated the efficacy of a formalin-inactivated vaccine, which could be derived directly from a circulating virus, to provide post-exposure protection. This strategy was evaluated using a prototypic highly pathogenic avian H5N1 strain, A/Vietnam/1203/2004, and demonstrated rapid induction of adaptive immune responses providing protection in a mammalian model of lethal infection. Additionally, this post-exposure vaccine was highly efficacious when administered 24 hours after exposure. This study offers a platform for developing effective post-exposure vaccines for treatment of highly virulent influenza infections. PMID:27405487

  13. Expression of Two N1 Clones with Single Amino Acid Dissimilarity of Avian Influenza H5N1 Virus

    Directory of Open Access Journals (Sweden)

    RISZA HARTAWAN

    2012-12-01

    Full Text Available Two clones of N1 gene derived from isolate A/Dk/Tangerang/Bbalitvet-ACIAR-TE11/2007 (H5N1 exhibit single mismatch of amino acid sequence at position 242 that is threonine and methionine for the clone #3 and #5, respectively. In order to evaluate the effect of the amino acid substitution, these clones were inserted into two different expression vectors that are pEGFP-C1 and pcDNA-3.3 TOPO® TA cloning. Subsequently, the respective recombinant clones were transfected into eukaryotic cells, including CEF, RK13 and VERO using Lipofectamine ‘plus’ reagent. As a result, the clone #3 retaining atypical sequence showed lower expression level rather than the clone #15 in both vectors and all type of cells. The 3D conformational modelling revealed that the mutation occurs in the inner part of glycoprotein embedded within envelope or matrix. Therefore, the missense mutation seems has no effect on the antigenic properties of neuraminidase but this substitution by any means causes lethal mutagenesis in the individual gene expression by reducing level of protein transcript.

  14. Risk factors for the occurrence and spread of Highly Pathogenic Avian Influenza H5N1 in commercial poultry farms in Kano, Nigeria

    Directory of Open Access Journals (Sweden)

    AM Wakawa,

    2012-12-01

    Full Text Available Outbreaks of Highly Pathogenic Avian Influenza (HPAI subtype H5N1 occurred previously for three consecutive years, 2006, 2007 and 2008 in Kano State, Nigeria, causing heavy economic losses to farmers and the government. It was against this background that risk factors for the occurrence and spread of HPAI H5N1 among commercial poultry farms in the State were evaluated. A total of 64 farms comprising 32 affected (AF and 32 non-affected (NAF farms were enrolled for this study. Questionnaires were designed and administered to the selected farms through interviews with farm owners or farm managers during on-site visits. Information on flock profile including farm characteristics and environment, husbandry practices, biosecurity practices, farm trade practices and employee activities were obtained and analyzed. Pearson Chi square and Fisher’s exact tests were used to compare categorical variables. Values of p< 0.05 were considered significant. Odds ratios (OR and 95% confidence intervals (CI were calculated to measure the strength and statistical significance of associations between the variables and occurrence and spread of HPAI H5N1 in commercial poultry farms in the State. The most significant risk factors were the presence of untreated surface water on farms (OR 18.6, 95%CI 2.24 – 154.34, p = 0.001, exchange of egg crates between traders and farmers (OR 12.1, 95%CI 1.43 – 102.61, p = 0.006, allowing egg crates of traders into poultry pens (OR 11.67, 95%CI 2.37 – 57.86, p = 0.001 and allowing rodents/wild birds access to poultry feed (OR 3.65, 95%CI 0.23 – 1.87, p = 0.024. It was recommended that veterinary inspection to enforce and encourage best biosecurity practices for the poultry farms should be introduced and sustained.

  15. 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.

  16. PDlim2 selectively interacts with the PDZ binding motif of highly pathogenic avian H5N1 influenza A virus NS1.

    Directory of Open Access Journals (Sweden)

    Jia Yu

    Full Text Available The multi-functional NS1 protein of influenza A virus is a viral virulence determining factor. The last four residues at the C-terminus of NS1 constitute a type I PDZ domain binding motif (PBM. Avian influenza viruses currently in circulation carry an NS1 PBM with consensus sequence ESEV, whereas human influenza viruses bear an NS1 PBM with consensus sequence RSKV or RSEV. The PBM sequence of the influenza A virus NS1 is reported to contribute to high viral pathogenicity in animal studies. Here, we report the identification of PDlim2 as a novel binding target of the highly pathogenic avian influenza virus H5N1 strain with an NS1 PBM of ESEV (A/Chicken/Henan/12/2004/H5N1, HN12-NS1 by yeast two-hybrid screening. The interaction was confirmed by in vitro GST pull-down assays, as well as by in vivo mammalian two-hybrid assays and bimolecular fluorescence complementation assays. The binding was also confirmed to be mediated by the interaction of the PDlim2 PDZ domain with the NS1 PBM motif. Interestingly, our assays showed that PDlim2 bound specifically with HN12-NS1, but exhibited no binding to NS1 from a human influenza H1N1 virus bearing an RSEV PBM (A/Puerto Rico/8/34/H1N1, PR8-NS1. A crystal structure of the PDlim2 PDZ domain fused with the C-terminal hexapeptide from HN12-NS1, together with GST pull-down assays on PDlim2 mutants, reveals that residues Arg16 and Lys31 of PDlim2 are critical for the binding between PDlim2 and HN12-NS1. The identification of a selective binding target of HN12-NS1 (ESEV, but not PR8-NS1 (RSEV, enables us to propose a structural mechanism for the interaction between NS1 PBM and PDlim2 or other PDZ-containing proteins.

  17. Highly pathogenic avian influenza virus H5N1 infection in a long-distance migrant shorebird under migratory and non-migratory states.

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    Leslie A Reperant

    Full Text Available Corticosterone regulates physiological changes preparing wild birds for migration. It also modulates the immune system and may lead to increased susceptibility to infection, with implications for the spread of pathogens, including highly pathogenic avian influenza virus (HPAIV H5N1. The red knot (Calidris canutus islandica displays migratory changes in captivity and was used as a model to assess the effect of high plasma concentration of corticosterone on HPAIV H5N1 infection. We inoculated knots during pre-migration (N = 6, fueling (N = 5, migration (N = 9 and post-migration periods (N = 6. Knots from all groups shed similar viral titers for up to 5 days post-inoculation (dpi, peaking at 1 to 3 dpi. Lesions of acute encephalitis, associated with virus replication in neurons, were seen in 1 to 2 knots per group, leading to neurological disease and death at 5 to 11 dpi. Therefore, the risk of HPAIV H5N1 infection in wild birds and of potential transmission between wild birds and poultry may be similar at different times of the year, irrespective of wild birds' migratory status. However, in knots inoculated during the migration period, viral shedding levels positively correlated with pre-inoculation plasma concentration of corticosterone. Of these, knots that did not become productively infected had lower plasma concentration of corticosterone. Conversely, elevated plasma concentration of corticosterone did not result in an increased probability to develop clinical disease. These results suggest that birds with elevated plasma concentration of corticosterone at the time of migration (ready to migrate may be more susceptible to acquisition of infection and shed higher viral titers--before the onset of clinical disease--than birds with low concentration of corticosterone (not ready for take-off. Yet, they may not be more prone to the development of clinical disease. Therefore, assuming no effect of sub-clinical infection on the

  18. 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.

  19. Domestic Ducks and H5N1 Influenza Epidemic, Thailand

    OpenAIRE

    Songserm, Thaweesak; Jam-on, Rungroj; Sae-Heng, Numdee; Meemak, Noppadol; Hulse-Post, Diane J.; Sturm-Ramirez, Katharine M.; Webster, Robert G.

    2006-01-01

    In addition to causing 12 human deaths and 17 cases of human infection, the 2004 outbreak of H5N1 influenza virus in Thailand resulted in the death or slaughter of 60 million domestic fowl and the disruption of poultry production and trade. After domestic ducks were recognized as silent carriers of H5N1 influenza virus, government teams went into every village to cull flocks in which virus was detected; these team efforts markedly reduced H5N1 infection. Here we examine the pathobiology and e...

  20. Prime-Boost Immunization Using a DNA Vaccine Delivered by Attenuated Salmonella enterica Serovar Typhimurium and a Killed Vaccine Completely Protects Chickens from H5N1 Highly Pathogenic Avian Influenza Virus▿

    OpenAIRE

    Pan, Zhiming; Zhang, Xiaoming; Geng, Shizhong; Fang, Qiang; You, Meng; Zhang, Lei; Jiao, Xinan; Liu, Xiufan

    2010-01-01

    H5N1 highly pathogenic avian influenza virus (HPAIV) has posed a great threat not only for the poultry industry but also for human health. However, an effective vaccine to provide a full spectrum of protection is lacking in the poultry field. In the current study, a novel prime-boost vaccination strategy against H5N1 HPAIV was developed: chickens were first orally immunized with a hemagglutinin (HA) DNA vaccine delivered by attenuated Salmonella enterica serovar Typhimurium, and boosting with...

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

    International Nuclear Information System (INIS)

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

  2. The East Jakarta Project: surveillance for highly pathogenic avian influenza A(H5N1) and seasonal influenza viruses in patients seeking care for respiratory disease, Jakarta, Indonesia, October 2011-September 2012.

    Science.gov (United States)

    Storms, A D; Kusriastuti, R; Misriyah, S; Praptiningsih, C Y; Amalya, M; Lafond, K E; Samaan, G; Triada, R; Iuliano, A D; Ester, M; Sidjabat, R; Chittenden, K; Vogel, R; Widdowson, M A; Mahoney, F; Uyeki, T M

    2015-12-01

    Indonesia has reported the most human infections with highly pathogenic avian influenza (HPAI) A(H5N1) virus worldwide. We implemented enhanced surveillance in four outpatient clinics and six hospitals for HPAI H5N1 and seasonal influenza viruses in East Jakarta district to assess the public health impact of influenza in Indonesia. Epidemiological and clinical data were collected from outpatients with influenza-like illness (ILI) and hospitalized patients with severe acute respiratory infection (SARI); respiratory specimens were obtained for influenza testing by real-time reverse transcription-polymerase chain reaction. During October 2011-September 2012, 1131/3278 specimens from ILI cases (34·5%) and 276/1787 specimens from SARI cases (15·4%) tested positive for seasonal influenza viruses. The prevalence of influenza virus infections was highest during December-May and the proportion testing positive was 76% for ILI and 36% for SARI during their respective weeks of peak activity. No HPAI H5N1 virus infections were identified, including hundreds of ILI and SARI patients with recent poultry exposures, whereas seasonal influenza was an important contributor to acute respiratory disease in East Jakarta. Overall, 668 (47%) of influenza viruses were influenza B, 384 (27%) were A(H1N1)pdm09, and 359 (25%) were H3. While additional data over multiple years are needed, our findings suggest that seasonal influenza prevention efforts, including influenza vaccination, should target the months preceding the rainy season.

  3. Expression of H5 hemagglutinin vaccine antigen in common duckweed (Lemna minor) protects against H5N1 high pathogenicity avian influenza virus challenge in immunized chickens.

    Science.gov (United States)

    Bertran, Kateri; Thomas, Colleen; Guo, Xuan; Bublot, Michel; Pritchard, Nikki; Regan, Jeffrey T; Cox, Kevin M; Gasdaska, John R; Dickey, Lynn F; Kapczynski, Darrell R; Swayne, David E

    2015-07-01

    A synthetic hemagglutinin (HA) gene from the highly pathogenic avian influenza (HPAI) virus A/chicken/Indonesia/7/2003 (H5N1) (Indo/03) was expressed in aquatic plant Lemna minor (rLemna-HA). In Experiment 1, efficacy of rLemna-HA was tested on birds immunized with 0.2μg or 2.3 μg HA and challenged with 10(6) mean chicken embryo infectious doses (EID50) of homologous virus strain. Both dosages of rLemna-HA conferred clinical protection and dramatically reduced viral shedding. Almost all the birds immunized with either dosage of rLemna-HA elicited HA antibody titers against Indo/03 antigen, suggesting an association between levels of anti-Indo/03 antibodies and protection. In Experiment 2, efficacy of rLemna-HA was tested on birds immunized with 0.9 μg or 2.2 μg HA and challenged with 10(6) EID50 of heterologous H5N1 virus strains A/chicken/Vietnam/NCVD-421/2010 (VN/10) or A/chicken/West Java/PWT-WIJ/2006 (PWT/06). Birds challenged with VN/10 exhibited 100% survival regardless of immunization dosage, while birds challenged with PWT/06 had 50% and 30% mortality at 0.9 μg HA and 2.2 μg HA, respectively. For each challenge virus, viral shedding titers from 2.2 μg HA vaccinated birds were significantly lower than those from 0.9μg HA vaccinated birds, and titers from both immunized groups were in turn significantly lower than those from sham vaccinated birds. Even if immunized birds elicited HA titers against the vaccine antigen Indo/03, only the groups challenged with VN/10 developed humoral immunity against the challenge antigen. None (rLemna-HA 0.9 μg HA) and 40% (rLemna-HA 2.2 μg HA) of the immunized birds challenged with PWT/06 elicited pre-challenge antibody titers, respectively. In conclusion, Lemna-expressed HA demonstrated complete protective immunity against homologous challenge and suboptimal protection against heterologous challenge, the latter being similar to results from inactivated whole virus vaccines. Transgenic duckweed-derived HA could be a

  4. 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...

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

    Directory of Open Access Journals (Sweden)

    Wang Wei

    2011-03-01

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

  6. Additional Evidence That the Polymerase Subunits Contribute to the Viral Replication and the Virulence of H5N1 Avian Influenza Virus Isolates in Mice.

    Directory of Open Access Journals (Sweden)

    Xiao Qu

    Full Text Available Genetically similar H5N1 viruses circulating in the avian reservoir exhibit different levels of pathogenicity in mice. In this study, we characterized two highly pathogenic H5N1 avian isolates--A/Hunan/316/2005 (HN05, which is highly pathogenic in mice, and A/Hubei/489/2004 (HB04, which is nonpathogenic. In mammalian cells, HN05 replicates more efficiently than HB04, although both viruses have similar growth kinetics in avian cells. We used reverse genetics to generate recombinant H5N1 strains containing genes from HN05 and HB04 and examined their virulence. HN05 genes encoding the polymerase complex determine pathogenicity and viral replication ability both in vitro and in vivo. The PB2 subunit plays an important role in enhancing viral replication, and the PB1 and PA subunits contribute mainly to pathogenicity in mice. These results can be used to elucidate host-range expansion and the molecular basis of the high virulence of H5N1 viruses in mammalian species.

  7. Kepekaan Telur Spesific Pathogen Free dan Clean Egg Terhadap Virus Flu Burung (SENSITIVITY OF SPESIFIC PATHOGEN FREE EGGS AND CLEAN EGG TO THE AVIAN INFLUENZA VIRUSES SUBTYPE H5N1

    Directory of Open Access Journals (Sweden)

    Gusti Ayu Yuniati Kencana

    2014-05-01

    Full Text Available Avian Influenza which is  in Indonesia  known as Flu Burung  is caused by the avian influenza virussubtype H5N1 (AIV-H5N1. Vaccination is one of the major strategies for preventing and eradicatingAIV-H5N1 in Indonesia. Several factors can affect the potential vaccine such as viral content and mediaused for the propagation of the virus. One of the media commonly used to propagate  the virus is pathogenspecific free (SPF embryonated chicken eggs. However, as the SPF eggs production is limited and expensive,the use of clean embryonated chicken eggs as an alternative need to examined. This study aimed todetermine the sensitivity of SPF and clean embryonated chicken eggs to the AIV-H5N1. The virus usedwas seed avian influenza virus (A/ Chicken/West Java (Subang/29/2007  which haa previously werepropagated  in SPF eggs and the Clean Eggs. The virus titer was determined as Embryo infective Dose 50%(EID50 using Reed and Muench method. Sensitivity of SPF eggs and Clean Egg to the VAI-H5N1 wascompared using  Chi-square statistical analysis. The titers of Avian Influenza Virus subtype H5N1 were106.83EID50/0.1ml in SPF eggs and 106.17EID50/0.1 ml in the Clean Eggs. Statistical analysis showed that,the sensitivity of SPF Eggs and Egg Clean  for the propagation of the VAI-H5N1 was not significantlydifferent.

  8. DNA probe modified with 3-iron bis(dicarbollide) for electrochemical determination of DNA sequence of Avian Influenza Virus H5N1.

    Science.gov (United States)

    Grabowska, Iwona; Stachyra, Anna; Góra-Sochacka, Anna; Sirko, Agnieszka; Olejniczak, Agnieszka B; Leśnikowski, Zbigniew J; Radecki, Jerzy; Radecka, Hanna

    2014-01-15

    In this work, we report on oligonucleotide probes bearing metallacarborane [3-iron bis(dicarbollide)] redox label, deposited on gold electrode for electrochemical determination of DNA sequence derived from Avian Influenza Virus (AIV), type H5N1. The oligonucleotide probes containing 5'-terminal NH2 group were covalently attached to the electrode, via NHS/EDC coupling to 3-mercaptopropionic acid SAM, previously deposited on the surface of gold. The changes in redox activity of Fe(III) centre of the metallacarborane complex before and after hybridization process was used as analytical signal. The signals generated upon hybridization with targets such as complementary or non-complementary 20-mer ssDNA or various PCR products consisting of 180-190 bp (dsDNA) were recorded by Osteryoung square-wave voltammetry (OSWV). The developed system was very sensitive towards targets containing sequence complementary to the probe with the detection limit estimated as 0.03 fM (S/N=3.0) and 0.08 fM (S/N=3.0) for 20-mer ssDNA and for dsDNA (PCR product), respectively. The non-complementary targets generated very weak responses. Furthermore, the proposed genosensor was suitable for discrimination of PCR products with different location of the complementarity region. PMID:23958581

  9. Genetic and biological characterization of avian influenza H5N1 viruses isolated from wild birds and poultry in Western Siberia.

    Science.gov (United States)

    Sharshov, Kirill; Romanovskaya, Alesia; Uzhachenko, Roman; Durymanov, Alexander; Zaykovskaya, Anna; Kurskaya, Olga; Ilinykh, Philipp; Silko, Nikita; Kulak, Mikhail; Alekseev, Alexander; Zolotykh, Sergei; Shestopalov, Alexander; Drozdov, Iliya

    2010-07-01

    Three viruses included in the study were isolated from dead birds (A/duck/Omsk/1822/2006, A/chicken/Reshoty/02/2006, and A/duck/Tuva/01/2006), whereas the virus A/common gull/Chany/P/2006 was isolated from an apparently healthy gull during outbreaks of highly pathogenic avian influenza in Russia in 2006. The intravenous pathogenicity index (IVPI) of viruses A/duck/Omsk/1822/2006, A/chicken/Reshoty/02/2006, and A/duck/Tuva/01/2006 ranged from 2.7 to 3.0, while the virus A/common gull/Chany/P/2006 had a markedly lower IVPI of 1.7. The virus A/common gull/Chany/P/2006 had a unique pattern of six amino acid substitutions in the regions of viral proteins crucial for virulence of H5N1 viruses. We hypothesize that these substitutions may affect the pathogenicity of A/common gull/Chany/P/2006.

  10. Pathogenicity of Genetically Similar, H5N1 Highly Pathogenic Avian Influenza Virus Strains in Chicken and the Differences in Sensitivity among Different Chicken Breeds.

    Science.gov (United States)

    Matsuu, Aya; Kobayashi, Tomoko; Patchimasiri, Tuangthong; Shiina, Takashi; Suzuki, Shingo; Chaichoune, Kridsada; Ratanakorn, Parntep; Hiromoto, Yasuaki; Abe, Haruka; Parchariyanon, Sujira; Saito, Takehiko

    2016-01-01

    Differences in the pathogenicity of genetically closely related H5N1 highly pathogenic avian influenza viruses (HPAIVs) were evaluated in White Leghorn chickens. These viruses varied in the clinical symptoms they induced, including lethality, virus shedding, and replication in host tissues. A comparison of the host responses in the lung, brain, and spleen suggested that the differences in viral replication efficiency were related to the host cytokine response at the early phase of infection, especially variations in the proinflammatory cytokine IL-6. Based on these findings, we inoculated the virus that showed the mildest pathogenicity among the five tested, A/pigeon/Thailand/VSMU-7-NPT/2004, into four breeds of Thai indigenous chicken, Phadu-Hung-Dang (PHD), Chee, Dang, and Luang-Hung-Khao (LHK), to explore effects of genetic background on host response. Among these breeds, Chee, Dang, and LHK showed significantly longer survival times than White Leghorns. Virus shedding from dead Thai indigenous chickens was significantly lower than that from White Leghorns. Although polymorphisms were observed in the Mx and MHC class I genes, there was no significant association between the polymorphisms in these loci and resistance to HPAIV.

  11. Pathogenicity of Genetically Similar, H5N1 Highly Pathogenic Avian Influenza Virus Strains in Chicken and the Differences in Sensitivity among Different Chicken Breeds

    Science.gov (United States)

    Matsuu, Aya; Kobayashi, Tomoko; Patchimasiri, Tuangthong; Shiina, Takashi; Suzuki, Shingo; Chaichoune, Kridsada; Ratanakorn, Parntep; Hiromoto, Yasuaki; Abe, Haruka; Parchariyanon, Sujira; Saito, Takehiko

    2016-01-01

    Differences in the pathogenicity of genetically closely related H5N1 highly pathogenic avian influenza viruses (HPAIVs) were evaluated in White Leghorn chickens. These viruses varied in the clinical symptoms they induced, including lethality, virus shedding, and replication in host tissues. A comparison of the host responses in the lung, brain, and spleen suggested that the differences in viral replication efficiency were related to the host cytokine response at the early phase of infection, especially variations in the proinflammatory cytokine IL-6. Based on these findings, we inoculated the virus that showed the mildest pathogenicity among the five tested, A/pigeon/Thailand/VSMU-7-NPT/2004, into four breeds of Thai indigenous chicken, Phadu-Hung-Dang (PHD), Chee, Dang, and Luang-Hung-Khao (LHK), to explore effects of genetic background on host response. Among these breeds, Chee, Dang, and LHK showed significantly longer survival times than White Leghorns. Virus shedding from dead Thai indigenous chickens was significantly lower than that from White Leghorns. Although polymorphisms were observed in the Mx and MHC class I genes, there was no significant association between the polymorphisms in these loci and resistance to HPAIV. PMID:27078641

  12. Phylodynamics of H5N1 Highly Pathogenic Avian Influenza in Europe, 2005–2010: Potential for Molecular Surveillance of New Outbreaks

    Directory of Open Access Journals (Sweden)

    Mohammad A. Alkhamis

    2015-06-01

    Full Text Available Previous Bayesian phylogeographic studies of H5N1 highly pathogenic avian influenza viruses (HPAIVs explored the origin and spread of the epidemic from China into Russia, indicating that HPAIV circulated in Russia prior to its detection there in 2005. In this study, we extend this research to explore the evolution and spread of HPAIV within Europe during the 2005–2010 epidemic, using all available sequences of the hemagglutinin (HA and neuraminidase (NA gene regions that were collected in Europe and Russia during the outbreak. We use discrete-trait phylodynamic models within a Bayesian statistical framework to explore the evolution of HPAIV. Our results indicate that the genetic diversity and effective population size of HPAIV peaked between mid-2005 and early 2006, followed by drastic decline in 2007, which coincides with the end of the epidemic in Europe. Our results also suggest that domestic birds were the most likely source of the spread of the virus from Russia into Europe. Additionally, estimates of viral dispersal routes indicate that Russia, Romania, and Germany were key epicenters of these outbreaks. Our study quantifies the dynamics of a major European HPAIV pandemic and substantiates the ability of phylodynamic models to improve molecular surveillance of novel AIVs.

  13. Investigating a crow die-off in January-February 2011 during the introduction of a new clade of highly pathogenic avian influenza virus H5N1 into Bangladesh.

    Science.gov (United States)

    Khan, Salah Uddin; Berman, Lashondra; Haider, Najmul; Gerloff, Nancy; Rahman, Md Z; Shu, Bo; Rahman, Mustafizur; Dey, Tapan Kumar; Davis, Todd C; Das, Bidhan Chandra; Balish, Amanda; Islam, Ausraful; Teifke, Jens P; Zeidner, Nord; Lindstrom, Steven; Klimov, Alexander; Donis, Ruben O; Luby, Stephen P; Shivaprasad, H L; Mikolon, Andrea B

    2014-03-01

    We investigated unusual crow mortality in Bangladesh during January-February 2011 at two sites. Crows of two species, Corvus splendens and C. macrorhynchos, were found sick and dead during the outbreaks. In selected crow roosts, morbidity was ~1 % and mortality was ~4 % during the investigation. Highly pathogenic avian influenza virus H5N1 clade 2.3.2.1 was isolated from dead crows. All isolates were closely related to A/duck/India/02CA10/2011 (H5N1) with 99.8 % and A/crow/Bangladesh/11rs1984-15/2011 (H5N1) virus with 99 % nucleotide sequence identity in their HA genes. The phylogenetic cluster of Bangladesh viruses suggested a common ancestor with viruses found in poultry from India, Myanmar and Nepal. Histopathological changes and immunohistochemistry staining in brain, pancreas, liver, heart, kidney, bursa of Fabricius, rectum, and cloaca were consistent with influenza virus infection. Through our limited investigation in domesticated birds near the crow roosts, we did not identify any samples that tested positive for influenza virus A/H5N1. However, environmental samples collected from live-bird markets near an outbreak site during the month of the outbreaks tested very weakly positive for influenza virus A/H5N1 in clade 2.3.2.1-specific rRT-PCR. Continuation of surveillance in wild and domestic birds may identify evolution of new avian influenza virus and associated public-health risks.

  14. 2株H5N1亚型禽流感病毒人工感染鸭的11项血液生化指标测定%Eleven Blood Biochemical Indexes Assay of Ducks Experimentally Infected with Two Avian Influenza Viruses(H5N1)

    Institute of Scientific and Technical Information of China (English)

    叶远兰; 周泉鹤; 李玉谷

    2011-01-01

    鸭肌肉接种禽流感病毒A/duck/Guangdong/185/2004(H5N1)和A/duck/Guangdong/221/2004(H5N1)后,血清中的丙氨酸氨基转移酶、天门冬氨酸氨基转移酶、碱性磷酸酶、总蛋白、肌酐、总胆固醇、钙和磷明显升高;葡萄糖和甘油三酯明显降低;白蛋白表现为先下降后升高的变化趋势.作者认为,检测这些血液生化指标对于诊断禽流感具有一定的参考价值.%Ducks intramuscularly inoculated with avian influenza virus strains, A/duck/Guangdong/185/2004 (H5N1) and A/duck/Guangdong/221/2004(H5N1), showed that the serum alanine aminotransferase(glutamic-pyruvic transminase), aspartate aminotransferase(glutamic-oxaloacetic transminase), alkaline phosphatase, total protein, creatinine, cholesterol, calcium and phosphorus were significantly increased; while glucose and triglycerides were obviously decreased; albumin was decreased at first and increased later. We considered that assaying these blood biochemical indexes were useful for diagnosing avian influenza.

  15. Progress in the Research of NS1 Protein from Avian Influenza Virus H5N1 Subtype%禽流感病毒H5N1亚型NS1蛋白的研究进展

    Institute of Scientific and Technical Information of China (English)

    刘宏生; 赵丹; 段艳婷

    2013-01-01

    NS1蛋白(non-structural protein 1)是A型流感病毒重要的非结构蛋白,作为流感病毒的致病因子,NS1通过多种方式增强病毒的致病性和毒力.就H5N1禽流感病毒NS1蛋白的结构与功能进行了综述.

  16. Pathological Change for ICR Mice Infected with Avian Influenza H5N1 Viruses%禽流感H5N1病毒感染ICR小鼠的病理变化

    Institute of Scientific and Technical Information of China (English)

    刘忠华; 李志东; 谭文雅; 黄韧

    2008-01-01

    [目的]通过鼻腔将H5N1禽流感病毒接种ICR小鼠,观察其主要器官组织的病理变化.[方法]麻醉ICR小鼠后将100 μL H5N1禽流感病毒原液用移液枪滴入接毒组小鼠鼻腔,接毒后14 d内每隔24 h取材一次,采用福尔马林固定,石蜡包埋、切片,HE染色.[结果]禽流感H5N1病毒感染ICR小鼠后表现出明显的病理改变.ICR小鼠的肺部病变最严重,表现为间质性肺炎,肺间质充血、水肿和淋巴细胞浸润,血管周围淋巴细胞浸润,毛细血管扩张,上皮细胞变性、坏死、脱落,并有充血和单核细胞浸润,肺泡壁明显增宽,血管充血.有的肺泡溶合,呈气肿状.肝、肾、脑等其它脏器也出现病变.[结论]禽流感ICR小鼠模型能复制出人类禽流感疾病的许多病理特征,禽流感H5N1病毒感染ICR小鼠的肺病理类似于人禽流感严重病例的肺病理.

  17. H5N1禽流感病毒感染雏鸭的病理学观察%Pathological observation of ducklings infected with H5N1 avian influenza virus

    Institute of Scientific and Technical Information of China (English)

    田伟; 吕晓萍; 马宏伟; 郑世民; 刘明

    2009-01-01

    通过眼观病变观察和组织病理学检查方法对H5N1禽流感病毒感染雏鸭的各器官组织病理变化进行了系统的研究,为H5N1禽流感病毒致病机制的研究及禽流感的-临床诊断提供理论依据.结果显示,雏鸭感染H5N1禽流感病毒后,除机体出现临床症状外,主要呈现明显的神经症状;病理剖检发现胰腺、肝、脾肿大,并见大小不一、数量不等的坏死灶;组织病理学检查发现全身各器官组织呈现出血、坏死和淋巴细胞浸润.经分析,多器官发生明显的细胞变性、坏死很可能是H5NI亚型禽流感病毒致病性的重要表现形式之一.

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

    Science.gov (United States)

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

  19. On Diagnose of Avian Influenza H5N1 and Its Study of Clinical Pathology%H5N1亚型禽流感的诊断及临床病理学研究

    Institute of Scientific and Technical Information of China (English)

    马国文; 李桂枝; 刘锴; 杨明霞

    2003-01-01

    对一起鸡传染病进行了病原鉴定并对其自然死亡的46例蛋鸡进行了临床病理学研究,结果表明,本起鸡病为A型禽流感,H5N1亚型,属高致死性(HPAI);急性热性出血性败血症;急性坏死性胰腺炎;非化脓性脑炎;卡他性上呼吸道炎;卡他性、间质性肺炎.

  20. 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.

  1. 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.

  2. 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.

  3. H5N1禽流感病毒羊驼重链单域抗体的制备和功能鉴定%Preparation and characterization of recombinant VHH antibody against H5N1 hemagglutinin from avian influenza virus

    Institute of Scientific and Technical Information of China (English)

    夏立亮; 吴标; 程亚庭; 包文静; 赵国屏; 王颖

    2012-01-01

    目的:获得具有中和活性、高特异性和稳定性的抗H5N1禽流感病毒血凝素蛋白(HA)的羊驼重链单域(VHH)抗体.方法:利用pET-22b表达载体诱导表达抗H5N1禽流感病毒HA VHH抗体蛋白,以包涵体形式表达的VHH抗体蛋白采用最优复性方法进行复性后,获得高纯度的VHH抗体,分别采用ELISA法鉴定VHH抗体的亲和力和热稳定性,采用血凝抑制实验鉴定抗体的特异性和体外中和活性.结果:经复性的抗H5N1禽流感HA VHH抗体对H5N1禽流感病毒HA具有良好的特异性.通过对三种不同复性方法比较,利用柱上复性的VHH23抗体具有较好的热稳定性,亲和力为9.1×10-7 mol/L,同时对H5N1禽流感病毒HA具有良好的体外中和活性.结论:实验结果表明通过原核表达获得具有较好中和活性、特异性及稳定性的抗H5N1禽流感病毒VHH抗体,为进一步开展抗体的体内病毒中和试验奠定良好基础.%Objective; To prepare and characterize camelid VHH antibody against hemagglutinin from H5N1 avian influenza virus. Methods: Recombinant expression vector pET-22b-VHH23 was constructed and VHH antibody against hemagglutinin from H5N1 a-vian influenza virus was expressed in E. Coli BL2l( DE3 ) strain by IPTG induction. As VHH antibody protein was expressed in inclusion body,there different refolding methods were compared for the refolding of VHH antibody in which the optimal methods were adopted for preparation of VHH antibody. The activity and thermal stability of VHH antibodies were tested by ELISA while hemagglutination-inhibition assay was perfomed to determine the specificity and neutralizing activity. Results; By using on-column refolding procedure, VHH antibody has been obtained with highest yield and good quality. This antibody specifically recognized hemagglutinin derived from H5N1 avian influenza virus as well as in vitro inhibition against hemagglutinin-mediated red blood cell agglutination. The affinity constant of VHH

  4. 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

    Avian influenza is a highly contagious disease of birds caused by A influenza viruses. The circulation in humans by the highly pathogenic H5N1 avian flu in the past few years have caused most pandemics and have heightened fear that the next influenza pandemic is due. Antibodies could be used as an efficient anti-virus agent in clinical therapy. The full-length HA of the A/Jiangsu/1/2007(H5N 1) about 1.7 kb was amplified, subcloned to the pFastBac vector and recombinant bacmid DNA was selected. The recombinant HA was expressed and purified HA about 70 ku was used as the antigen to immunize Balb/c mice. The whole H5N1 virus was used to select 5 mono-antibodies (mAbs), and all of them were tested using microneutralization assays. 8G10D7, one of the antibodies, had broad neutralizing effect against clade 2 and clade 9 H5N1 avian influenza A viruses, and the IC50 was from 1 : 256 to I ' 64. When detected with 8G10D7, all 4 viruses showed 70 ku and 43 ku protein band,which confirms that the binding site of the scFv antibodies were located at the HA1 domain. The nucleuses of MDCK cells infected by 4 viruses were colored purple, and red around the nucleus. 8Gl 0D7 showed HI activity to the 4 viruses, the HI has a positive correlation with neutralization concentration IC50, which also further confirms that the binding site of the scFv antibodies were located at the HA1 domain. When the mAb 8Gl 0D7 was used for the study of prophylaxis and therapeutic effect on influenza A viruses infection in an embryonated chicken eggs model. It had a complete 100% protection effect on the H5N1 viruses in avian host in the prophylactic and therapeutic groups. The 100% preventive protection effect could be reached when challenged with H5N1 avian influenza A viruse in human host in the prophylactic groups, and there is also a 87.5% protection effect with H5N1 viruses in human host in the therapeutic groups. Thereby, the study suggests that the mAb 8G10D7 could be used in therapies to

  5. Investigation on the source of the first human of avian influenza A (H5N1) case in Beijing%北京市首例人禽流感H5N1病例的感染来源调查

    Institute of Scientific and Technical Information of China (English)

    杨鹏; 梁慧洁; 黎新宇; 窦相峰; 王小莉; 张奕; 庞星火; 贺雄; 王全意; 师鉴; 马建新; 刘秀军; 齐顺祥; 黄芳; 石伟先; 彭晓晻; 吕燕宁

    2009-01-01

    Objective To investigate the source of the first human case of avian influenza A (H5N1) infection in Beijing. Methods Interviewing the relatives of the case and other key persons, collecting and detecting samples of related biological, epidemiological and environmental data of the case were conducted. Later, the infection source was thoroughly investigated. Results The case ever contacted a slaughtered duck 5 days prior to the onset of illness, and the duck was bought from a stall of a wet market in Yanjiao area of Hebei province. Ten environmental samples were collected in this stall and the neighboring stall of the market. Another 6 samples were tested positive for H5N1 virus by PCR method, with 5 virus strains isolated. The whole-genome sequencing indicated that the amino acid homology between the H5N1 virus strains from the environment and the virus isolated from the case reached 99.8%-100%. Conclusion From both epidemiological and virological evidence, it was proved that the first human case of avian influenza A (H5N1) infection in Beijing was infected by a duck that carrying H5N1 virus the case contacted 5 days proceeding the onset of illness.%目的 调查北京市首例人禽流感(H5N1)病例的感染来源.方法 通过对患者家属和其他关键人物访谈,检测患者标本以及流行病学关联的环境标本,对患者可能的感染来源进行追踪调查.结果 该患者在其发病前5天曾经接触过宰杀的鸭子(购自河北省燕郊某市场活禽摊位),采集该摊位及邻近活禽摊位的环境标本10份,经PCR方法检测有6份标本为H5N1亚型病毒核酸阳性,并通过鸡胚分离出5株H5N1亚型病毒.将从环境标本中分离的H5N1亚型病毒与患者体内分离的H5N1亚型病毒(禽源、属于Clade 2.3.4)进行全基因组序列比对,氨基酸同源性高达99.8%~100%.结论 流行病学和病原学双重证据表明,北京市首例人禽流感H5N1病例的感染来源为接触携带H5N1亚型禽流感病毒的鸭子.

  6. Evaluation of the antigenic relatedness and cross-protective immunity of the neuraminidase between human influenza A (H1N1) virus and highly pathogenic avian influenza A (H5N1) virus.

    Science.gov (United States)

    Lu, Xiuhua; Liu, Feng; Zeng, Hui; Sheu, Tiffany; Achenbach, Jenna E; Veguilla, Vic; Gubareva, Larisa V; Garten, Rebecca; Smith, Catherine; Yang, Hua; Stevens, James; Xu, Xiyan; Katz, Jacqueline M; Tumpey, Terrence M

    2014-04-01

    To determine the genetic and antigenic relatedness as well as the cross-protective immunity of human H1N1 and avian H5N1 influenza virus neuraminidase (NA), we immunized rabbits with either a baculovirus-expressed recombinant NA from A/Beijing/262/95 (BJ/262) H1N1 or A/Hong Kong/483/97 (HK/483) H5N1 virus. Cross-reactive antibody responses were evaluated by multiple serological assays and cross-protection against H5N1 virus challenge was evaluated in mice. In a neuraminidase inhibition (NI) test, the antisera exhibited substantial inhibition of NA activity of the homologous virus, but failed to inhibit the NA activity of heterologous virus. However, these antisera exhibited low levels of cross-reactivity measured by plaque size reduction, replication inhibition, single radial hemolysis, and ELISA assays. Passive immunization with HK/483 NA-specific antisera significantly reduced virus replication and disease, and afforded almost complete protection against lethal homologous virus challenge in mice. However, passive immunization with BJ/262 (H1N1) NA-specific antisera was ineffective at providing cross-protection against lethal H5N1 virus challenge and only slightly reduced weight loss. Substantial amino acid variation among the NA antigenic sites was observed between BJ/262 and HK/483 virus, which was consistent with the lack of cross-reactive NI activity by the antibody and limited cross-protective immunity in mice. These results show a strong correlation between the lack of cross-protective immunity and low structural similarities of NA from a human seasonal H1N1 virus and an avian H5N1 influenza virus.

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

    Directory of Open Access Journals (Sweden)

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

    Directory of Open Access Journals (Sweden)

    Nader Pourmand

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

  9. Progress on H5N1 Avian Influenza Virus and New Antiviral Drugs%H5Nl禽流感病毒及抗病毒新药的研究进展

    Institute of Scientific and Technical Information of China (English)

    边玲; 陈执中

    2008-01-01

    禽流感病毒(avian influenza virus,AIV)是引起鸟禽类烈性传染病的病毒.1997年发现AIV跨越物种障碍使人感染.H5N1是有强致病力的禽流感病毒,感染H5N1的患者死亡率高.本文综述了禽流感病毒致病机制研究以及抗H5N1禽流感病毒新药的进展,包括:神经氨酸苷酶新抑制剂及核酸基的抗禽流感病毒新药--免疫调节双链核糖核酸聚ICLC脂质体和反义寡核苷酸.

  10. 人高致病性H5N1亚型禽流感病毒NS1蛋白多克隆抗体的制备及鉴定%Preparation and characterization the polyclonal antibody of the nonstructural protein of human highly pathogenic H5N1 avian influenza viruses

    Institute of Scientific and Technical Information of China (English)

    蒋培余; 黄惠莲; 周洪昌; 徐伯赢; 顾福萍; 闵丽姗; 钟婧; 戴利成

    2013-01-01

    目的 制备高灵敏度和高特异性的人高致病性H5N1亚型禽流感病毒NS1蛋白抗体并对其效价进行初步评估.方法 构建含有H5N1亚型禽流感病毒NS1序列的pET-28a(+)重组载体的大肠埃希菌BL21(DE3),诱导表达NS1蛋白,并经Ni-NTA色谱柱亲和层析纯化获得NS1重组蛋白,并进行SDS-PAGE和Western Blot鉴定.以纯化的蛋白为抗原免疫新西兰大白兔,获得兔抗NS1血清,亲和纯化获得多克隆抗体.应用ELISA和Western Blot检测纯化抗体的效价和特异性.结果 NS1融合蛋白得到高表达,且纯度>90%,用该融合蛋白免疫新西兰大白兔后得到的抗NS1多克隆抗体,效价达1∶80 000,并特异性识别H5N1亚型禽流感病毒NS1蛋白.结论 获得了NS1多克隆抗体,具有较好的效价和特异性.%Objective Of this study was to prepare high sensitivity and high specificity of highly pathogenic H5N1 subtype avian influenza virus NS1 protein antibody and a preliminary assessment of its potency.Methods Construct pET-28a (+) recombinant vector containing the H5N1 subtype of avian influenza virus NS1 sequences of E.coli BL21 (DE3),induced expression of NS1 protein,NS1 recombinant protein was obtained by Ni-NTA column purified by affinity chromatography,and SDS-PAGE and Western Blot analysis.Purified protein antigen to immunize New Zealand white rabbits,obtained rabbit anti-NS1 serum,affinity-purified polyclonal antibodies.Using ELISA and Western Blot analysis of purified antibody titer and specificity.Results NS1 fusion protein was highly expressed in a purity of greater than 90%,with the fusion protein was used to immunize New Zealand white rabbits anti-NS1 polyclonal antibody titer of 1:80000,and specific recognition of the H5N1 subtype of avian influenza virus NS1 protein.Conclusions NS1 polyclonal antibodies to NS1 recombinant protein purified antigen,with better potency and specificity,and to prepare the conditions for the development of the H5N1 subtype of avian

  11. Progress in treatment of infection with highly pathogenic H5N1 avian influenza virus since 2005%关于WHO 2005年以来高致病性H5N1禽流感病毒的临床和治疗进展

    Institute of Scientific and Technical Information of China (English)

    杨子峰; 王丹芬; 钟南山; 陈敬贤

    2009-01-01

    自1997年中国香港特别行政区报道首例人感染H5N1禽流感病毒以来,截至2008年9月10日,这场在禽类中史无前例地持续流行、造成了人类感染并具有高病死率的疫情已经波及到15个国家和地区,总发病387例,死亡245例,其中我国疫情30例,病死率超过60%,防控形势十分严峻.本文旨在整理分析2005年以来世界卫生组织和全球对禽流感病毒临床防治研究成果及人感染H5N1禽流感病例报道的最新信息,力求提供一个防治人禽流感方面的较为全面而清晰的介绍.%Highly pathogenic H5N1 avian influenza virus(AIV) has spread unprecedentedly across the world since the first outbreak of human cases was reported in 1997 in Hong Kong, China. Until June 19th,2008,H5N1 virus resulted in sporadic but severe even fatal human cases in 15 countries,243 died in 385 reported human H5N1 infections,including 20 in China,and the overall mortality was more than 60%. These new appeared viruses and their capacity of transmission from birds to humans have raised a great deal of concern for a potential pandemic,and world health organization has promulgated a few recommendations or guidelines. This review provides an up-to-date information of research in H5N1 virus infection since 2005, and summarizes the epidemiology, clinical features, pathology, diagnosis, current therapeutic options and prevention strategies of H5N1 infection in humans.

  12. 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

    Directory of Open Access Journals (Sweden)

    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.

  13. Outbreaks of highly pathogenic avian influenza H5N1 clade 2.3.2.1c in hunting falcons and kept wild birds in Dubai implicate intercontinental virus spread.

    Science.gov (United States)

    Naguib, Mahmoud M; Kinne, Jörg; Chen, Honglin; Chan, Kwok-Hung; Joseph, Sunitha; Wong, Po-Chun; Woo, Patrick C Y; Wernery, Renate; Beer, Martin; Wernery, Ulrich; Harder, Timm C

    2015-11-01

    Highly pathogenic avian influenza viruses (HPAIVs) of subtype H5N1 have continued to perpetuate with divergent genetic variants in poultry within Asia since 2003. Further dissemination of Asian-derived H5 HPAIVs to Europe, Africa and, most recently, to the North American continent has occurred. We report an outbreak of HPAIV H5N1 among falcons kept for hunting and other wild bird species bred as falcon prey in Dubai, United Arab Emirates, during the autumn of 2014. The causative agent was identified as avian influenza virus subtype H5N1, clade 2.3.2.1c, by genetic and phylogenetic analyses. High mortality in infected birds was in accordance with systemic pathomorphological and histological alterations in affected falcons. Genetic analysis showed the HPAIV H5N1 of clade 2.3.2.1c is a reassortant in which the PB2 segment was derived from an Asian-origin H9N2 virus lineage. The Dubai H5N1 viruses were closely related to contemporary H5N1 HPAIVs from Nigeria, Burkina-Faso, Romania and Bulgaria. Median-joining network analysis of 2.3.2.1c viruses revealed that the Dubai outbreak was an episode of a westward spread of these viruses on a larger scale from unidentified Asian sources. The incursion into Dubai, possibly via infected captive hunting falcons returning from hunting trips to central Asian countries, preceded outbreaks in Nigeria and other West African countries. The alarmingly enhanced geographical mobility of clade 2.3.2.1.c and clade 2.3.4.4 viruses may represent another wave of transcontinental dissemination of Asian-origin HPAIV H5 viruses, such as the outbreak at Qinghai Lake caused by clade 2.2 (‘Qinghai’ lineage) in 2005.

  14. Intense circulation of A/H5N1 and other avian influenza viruses in Cambodian live-bird markets with serological evidence of sub-clinical human infections.

    Science.gov (United States)

    Horm, Srey Viseth; Tarantola, Arnaud; Rith, Sareth; Ly, Sowath; Gambaretti, Juliette; Duong, Veasna; Y, Phalla; Sorn, San; Holl, Davun; Allal, Lotfi; Kalpravidh, Wantanee; Dussart, Philippe; Horwood, Paul F; Buchy, Philippe

    2016-01-01

    Surveillance for avian influenza viruses (AIVs) in poultry and environmental samples was conducted in four live-bird markets in Cambodia from January through November 2013. Through real-time RT-PCR testing, AIVs were detected in 45% of 1048 samples collected throughout the year. Detection rates ranged from 32% and 18% in duck and chicken swabs, respectively, to 75% in carcass wash water samples. Influenza A/H5N1 virus was detected in 79% of samples positive for influenza A virus and 35% of all samples collected. Sequence analysis of full-length haemagglutinin (HA) and neuraminidase (NA) genes from A/H5N1 viruses, and full-genome analysis of six representative isolates, revealed that the clade 1.1.2 reassortant virus associated with Cambodian human cases during 2013 was the only A/H5N1 virus detected during the year. However, multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of HA and NA genes revealed co-circulation of at least nine low pathogenic AIVs from HA1, HA2, HA3, HA4, HA6, HA7, HA9, HA10 and HA11 subtypes. Four repeated serological surveys were conducted throughout the year in a cohort of 125 poultry workers. Serological testing found an overall prevalence of 4.5% and 1.8% for antibodies to A/H5N1 and A/H9N2, respectively. Seroconversion rates of 3.7 and 0.9 cases per 1000 person-months participation were detected for A/H5N1 and A/H9N2, respectively. Peak AIV circulation was associated with the Lunar New Year festival. Knowledge of periods of increased circulation of avian influenza in markets should inform intervention measures such as market cleaning and closures to reduce risk of human infections and emergence of novel AIVs. PMID:27436362

  15. 2株H5N1亚型禽流感病毒人工感染鸭的组织病理学观察%Histopathology of Ducks Experimentally Infected with Two Avian Influenza Viruses(H5N1)

    Institute of Scientific and Technical Information of China (English)

    叶远兰; 周泉鹤; 李玉谷

    2011-01-01

    鸭经肌肉接种禽流感病毒A/duck/Guangdong/185/2004(H5N1)和A/duck/Guangdong/221/2004(H5N1)后,2周内未见死亡,但具有一些显微和超微病理学变化,主要表现为呼吸道、消化道黏膜受损,心脏、肝脏、肺脏、肾脏、脑等器官一定程度的充血、淤血、出血、水肿及实质细胞变性、坏死和炎症等.%Ducks intramuscularly inoculated with two avian influenza virus isolates, A/duck/Guangdong/221/2004(HSN1)and A/duck/Guangdong/185/2004(H5N1), had micropathological and ultrapathological lessions in some degree in multiple organs, such as the damages of mucous membrane of respiratory and alimentary tract, and hyperemia, congestion, hemorrhage,edema, and cell degeneration, necrosis, inflammation or a combination of these features in the heart, liver, lung, kidney, andencephalon etc, but did not died in two weeks.

  16. Efficacy of single dose of a bivalent vaccine containing inactivated Newcastle disease virus and reassortant highly pathogenic avian influenza H5N1 virus against lethal HPAI and NDV infection in chickens.

    Directory of Open Access Journals (Sweden)

    Dong-Hun Lee

    Full Text Available Highly pathogenic avian influenza (HPAI and Newcastle disease (ND are 2 devastating diseases of poultry, which cause great economic losses to the poultry industry. In the present study, we developed a bivalent vaccine containing antigens of inactivated ND and reassortant HPAI H5N1 viruses as a candidate poultry vaccine, and we evaluated its immunogenicity and protective efficacy in specific pathogen-free chickens. The 6:2 reassortant H5N1 vaccine strain containing the surface genes of the A/Chicken/Korea/ES/2003(H5N1 virus was successfully generated by reverse genetics. A polybasic cleavage site of the hemagglutinin segment was replaced by a monobasic cleavage site. We characterized the reverse genetics-derived reassortant HPAI H5N1 clade 2.5 vaccine strain by evaluating its growth kinetics in eggs, minimum effective dose in chickens, and cross-clade immunogenicity against HPAI clade 1 and 2. The bivalent vaccine was prepared by emulsifying inactivated ND (La Sota strain and reassortant HPAI viruses with Montanide ISA 70 adjuvant. A single immunization with this vaccine induced high levels of hemagglutination-inhibiting antibody titers and protected chickens against a lethal challenge with the wild-type HPAI and ND viruses. Our results demonstrate that the bivalent, inactivated vaccine developed in this study is a promising approach for the control of both HPAI H5N1 and ND viral infections.

  17. Spatio-Temporal Occurrence Modeling of Highly Pathogenic Avian Influenza Subtype H5N1: A Case Study in the Red River Delta, Vietnam

    Directory of Open Access Journals (Sweden)

    Chinh C. Tran

    2013-11-01

    Full Text Available Highly Pathogenic Avian Influenza (HPAI subtype H5N1 poses severe threats to both animals and humans. Investigating where, when and why the disease occurs is important to help animal health authorities develop effective control policies. This study takes into account spatial and temporal occurrence of HPAI H5N1 in the Red River Delta of Vietnam. A two-stage procedure was used: (1 logistic regression modeling to identify and quantify factors influencing the occurrence of HPAI H5N1; and (2 a geostatistical approach to develop monthly predictive maps. The results demonstrated that higher average monthly temperatures and poultry density in combination with lower average monthly precipitation, humidity in low elevation areas, roughly from November to January and April to June, contribute to the higher occurrence of HPAI H5N1. Provinces near the Gulf of Tonkin, including Hai Phong, Hai Duong, Thai Binh, Nam Dinh and Ninh Binh are areas with higher probability of occurrence of HPAI H5N1.

  18. 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

    Directory of Open Access Journals (Sweden)

    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.

  19. Evaluation of antibody response in mice against avian influenza A (H5N1) strain neuraminidase expressed in yeast Pichia pastoris

    Indian Academy of Sciences (India)

    Murugan Subathra; Ponsekaran Santhakumar; Mangamoori Lakshmi Narasu; Syed Sultan Beevi; Sunil K Lal

    2014-06-01

    Avian influenza has raised many apprehension in the recent years because of its potential transmitability to humans. With the increasing emergence of drug-resistant avian influenza strains, development of potential vaccines are imperative to manage this disease. Two structural antigens, haemagglutinin and neuraminidase, have been the target candidates for the development of subunit vaccine against influenza. In an effort to develop a faster and economically beneficial vaccine, the neuraminidase gene of a highly pathogenic avian influenza isolate was cloned and expressed in the methylotrophic yeast Pichia pastoris. The recombinant neuraminidase (rNA) antigen was purified, and its bioactivity was analysed. The rNA was found to be functional, as determined by the neuraminidase assay. Four groups of mice were immunized with different concentrations of purified rNA antigen, which were adjuvanted with aluminium hydroxide. The immune response against rNA was analysed by enzyme-linked immunosorbent assay (ELISA) and neuraminidase inhibition assay. The mice groups immunized with 25 g and 10 g of antigen had a significant immune response against rNA. This method can be utilized for faster and cost-effective development of vaccines for a circulating and newer strain of avian influenza, and would aid in combating the disease in a pandemic situation, in which production time matters greatly.

  20. Virtual screening of Indonesian flavonoid as neuraminidase inhibitor of influenza a subtype H5N1

    Science.gov (United States)

    Parikesit, A. A.; Ardiansah, B.; Handayani, D. M.; Tambunan, U. S. F.; Kerami, D.

    2016-02-01

    Highly Pathogenic Avian Influenza (HPAI) H5N1 poses a significant threat to animal and human health worldwide. The number of H5N1 infection in Indonesia is the highest during 2005-2013, with a mortality rate up to 83%. A mutation that occurred in H5N1 strain made it resistant to commercial antiviral agents such as oseltamivir and zanamivir, so the more potent antiviral agent is needed. In this study, virtual screening of Indonesian flavonoid as neuraminidase inhibitor of H5N1 was conducted. Total 491 flavonoid compound obtained from HerbalDB were screened. Molecular docking was performed using MOE 2008.10. This research resulted in Guajavin B as the best ligand.

  1. Multiple introductions of a reassortant H5N1 avian influenza virus of clade 2.3.2.1c with PB2 gene of H9N2 subtype into Indian poultry.

    Science.gov (United States)

    Tosh, Chakradhar; Nagarajan, Shanmugasundaram; Kumar, Manoj; Murugkar, Harshad V; Venkatesh, Govindarajulu; Shukla, Shweta; Mishra, Amit; Mishra, Pranav; Agarwal, Sonam; Singh, Bharati; Dubey, Prashant; Tripathi, Sushil; Kulkarni, Diwakar D

    2016-09-01

    Highly pathogenic avian influenza (HPAI) H5N1 viruses are a threat to poultry in Asia, Europe, Africa and North America. Here, we report isolation and characterization of H5N1 viruses isolated from ducks and turkeys in Kerala, Chandigarh and Uttar Pradesh, India between November 2014 and March 2015. Genetic and phylogenetic analyses of haemagglutinin gene identified that the virus belonged to a new clade 2.3.2.1c which has not been detected earlier in Indian poultry. The virus possessed molecular signature for high pathogenicity to chickens, which was corroborated by intravenous pathogenicity index of 2.96. The virus was a reassortant which derives its PB2 gene from H9N2 virus isolated in China during 2007-2013. However, the neuraminidase and internal genes are of H5N1 subtype. Phylogenetic and network analysis revealed that after detection in China in 2013/2014, the virus moved to Europe, West Africa and other Asian countries including India. The analyses further indicated multiple introductions of H5N1 virus in Indian poultry and internal spread in Kerala. One of the outbreaks in ducks in Kerala is linked to the H5N1 virus isolated from wild birds in Dubai suggesting movement of virus probably through migration of wild birds. However, the outbreaks in ducks in Chandigarh and Uttar Pradesh were from an unknown source in Asia which also contributed gene pools to the outbreaks in Europe and West Africa. The widespread incidence of the novel H5N1 HPAI is similar to the spread of clade 2.2 ("Qinghai-like") virus in 2005, and should be monitored to avoid threat to animal and public health. PMID:27174088

  2. Avian influenza A(H7N9) and (H5N1) infections among poultry and swine workers and the general population in Beijing, China, 2013–2015

    Science.gov (United States)

    Yang, Peng; Ma, Chunna; Cui, Shujuan; Zhang, Daitao; Shi, Weixian; Pan, Yang; Sun, Ying; Lu, Guilan; Peng, Xiaomin; Zhao, Jiachen; Liu, Yimeng; Wang, Quanyi

    2016-01-01

    Although several studies have reported seroprevalences of antibody against avian influenza A(H7N9) virus among poultry workers in southern China, results have varied and data in northern China are scarce. To understand risks of H7N9 and H5N1 virus infections in northern China, a serological cohort study was conducted. Poultry workers, swine workers and the general population in Beijing, China, were evaluated through three surveys in November 2013, April 2014 and April 2015. The highest seroprevalence to H7N9 virus among poultry workers was recorded in the April 2014 and April 2015 surveys (0.4%), while that to H5N1 clade 2.3.4 or clade 2.3.2.1 virus was noted in the April 2014 survey (1.6% and 0.2%, respectively). The incidence of H7N9 virus infections among poultry workers (1.6/1000 person-months) was significantly lower than that of H5N1 clade 2.3.4 infections (3.8/1000 person-months) but higher than that of H5N1 clade 2.3.2.1 infections (0.3/1000 person-months). Compared with the general population, poultry workers were at higher risk of contracting H7N9 virus (IRR: 34.90; p poultry workers. PMID:27670286

  3. Highly pathogenic avian influenza virus H5N1 controls type I IFN induction in chicken macrophage HD-11 cells: a polygenic trait that involves NS1 and the polymerase complex

    Directory of Open Access Journals (Sweden)

    Liniger Matthias

    2012-01-01

    Full Text Available Abstract Background Influenza A viruses are well characterized to antagonize type I IFN induction in infected mammalian cells. However, limited information is available for avian cells. It was hypothesised that avian influenza viruses (AIV with distinct virulence may interact differently with the avian innate immune system. Therefore, the type I IFN responses induced by highly virulent and low virulent H5N1 AIV and reassortants thereof were analysed in chicken cells. Results The highly pathogenic (HP AIV A/chicken/Yamaguchi/7/04 (H5N1 (Yama did not induce type I IFN in infected chicken HD-11 macrophage-like cells. This contrasted with an NS1 mutant Yama virus (Yama-NS1A144V and with the attenuated H5N1 AIV A/duck/Hokkaido/Vac-1/04 (Vac carrying the haemagglutinin (HA of the Yama virus (Vac-Yama/HA, that both induced type I IFN in these cells. The substitution of the NS segment from Yama with that from Vac in the Yama backbone resulted in induction of type I IFN secretion in HD-11 cells. However, vice versa, the Yama NS segment did not prevent type I IFN induction by the Vac-Yama/HA virus. This was different with the PB1/PB2/PA segment reassortant Yama and Vac-Yama/HA viruses. Whereas the Yama virus with the Vac PB1/PB2/PA segments induced type I IFN in HD-11 cells, the Vac-Yama/HA virus with the Yama PB1/PB2/PA segments did not. As reported for mammalian cells, the expression of H5N1 PB2 inhibited the activation of the IFN-β promoter in chicken DF-1 fibroblast cells. Importantly, the Yama PB2 was more potent at inhibiting the IFN-β promoter than the Vac PB2. Conclusions The present study demonstrates that the NS1 protein and the polymerase complex of the HPAIV Yama act in concert to antagonize chicken type I IFN secretion in HD-11 cells. PB2 alone can also exert a partial inhibitory effect on type I IFN induction. In conclusion, the control of type I IFN induction by H5N1 HPAIV represents a complex phenotype that involves a particular viral

  4. H5N1亚型禽流感病毒低剂量感染小鼠发病模型的建立%Pathogenicity of a low-dosage inoculation of H5N1 avian influenza virus in mice

    Institute of Scientific and Technical Information of China (English)

    李旭勇; 郭晶; 施建忠; 李雁冰; 陈化兰

    2011-01-01

    为模拟哺乳动物感染H5亚型高致病性禽流感病毒(HPAIV)的发病进程,本研究采用对哺乳动物高度致病的H5N1亚型HPAIV株A/bar-headed goose/Qinghai/3/05 (BHG/3/05),以低剂量鼻腔接种小鼠,观察发病、存活、病毒复制及组织病理损伤情况.结果显示,100.4 EID50即能够100%感染小鼠,但发病表现缓慢,死亡延迟至8d以后,存活达60%;体内病毒复制可持续10 d以上,感染后前3d病毒的增殖限于呼吸道,随后扩散至脑、脾、肾等其他器官;组织病理学观察肺脏早期表现出渗出性炎症,第10d发展为典型的间质性肺炎.本研究结果为探讨人禽流感的病理发生机制提供了具有价值的模型.%To imitate the natural infection of H5N1 subtype avian influenza virus (AIV) in animals, BALB/c mice were inoculated with a low-dosage (100.4 EID50) of H5N1 AIV A/bar-headed goose/3/05 (BHG/3/05) strain and were observed for weight gain and mortality. Different organs of the mice were also collected at different time points after infection for virus titration and pathologic examination. The results indicated that all of the inoculated mice were successfully infected by the virus, and 60% of mice survived during the 2 weeks observation period. Virus could be detected from organs of mice at 3, 5, 7, and 10 days, but not at 14 days post infection (p.I.). The virus was only detected in the lung of mice on day 3 p.I., then gradually spread to spleen, kidney and brain. Histopathologic examination revealed the pneumonia with significant infiltration of inflammatory cells in the lung section at day 3 p.I., and interstitial pneumonia at day 10 p.I.. These results are useful for a better understanding of the pathogenesis of H5N1 influenza virus infection in nature.

  5. Susceptibility of Muscovy (Cairina Moschata) and mallard ducks (Anas Platyrhynchos) to experimental infections by different genotypes of H5N1 avian influenza viruses

    DEFF Research Database (Denmark)

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

    2011-01-01

    exposed to infection with H5N1. To do this, an experimental study on infections with different genotypes of H5N1 in mallards and Muscovy ducks have been conducted, where it was found that the mortality of the inoculated Muscovy ducks was at least 80%, regardless of the virus strain employed. In contrast......, the mortality of the mallards ranged from nil to 100%, which suggests that Muscovy ducks are more susceptible to HPAIV H5N1 infection in terms of disease development and mortality. It was also found that higher virus titers developed in vital organs of Muscovy ducks compared to mallards, particularly...... in the brain. Due to their high susceptibility, it is unlikely that Muscovy ducks act as a silent reservoir. The virus strains used in this study, to a certain degree, differed in their virulence properties to the bird species in question....

  6. 禽流感病毒H5N1亚型NS1蛋白的真核表达及其在细胞中的分布%Eukaryotic expression and localization of NS1 protein of H5N1 avian influenza virus in infected cells

    Institute of Scientific and Technical Information of China (English)

    卞倩; 张文帅; 迟莹; 李燕; 焦永军

    2011-01-01

    To localized the nonstructure proteinl (NS1) of human H5N1 serotype avian influenza virus (AFV) in infected cells, the NS1 gene was amplified by RT-PCR and cloned into eukaryotic expression plasmid of pXJ40-HA, the resultant recombinant plasmid was transfected into 293T cells, and the expressed NS1 was identified by western blot assay. The localization of NS1 protein in H1299 cells was detected by immunofluorescence assay (IFA), and the results indicated that NS1 protein mainly localized in cell nucleus. This result would be benefited for further study of the function of NS1 protein and the mechanism of diseases induced by AIV serotype H5N1.%为构建禽流感病毒(AIV) H5N1亚型非结构蛋白NS1的真核表达载体,并鉴定其在哺乳动物细胞中的表达与分布,本研究采用RT-PCR技术,从甲型流感病毒的总RNA中扩增NS1全长基因,并将其克隆于pXJ40中,构建真核表达载体pXJ40-HA-NSl.将该重组质粒转染293T细胞,通过western blot方法鉴定表达的NS1蛋白;并以免疫荧光技术观察NS1在H1299细胞中的分布与定位.Western blot结果显示NS1基因编码蛋白获得表达,免疫荧光检测显示NS1蛋白主要存在于细胞核中.本研究为NS1蛋白功能和H5N1亚型AIV致病机制的研究奠定了基础.

  7. Preparation and characterization of recombinant Llama VHH-human IgGFc chimeric antibody against H5N1 hemagglutinin from avian influenza virus%羊驼抗H5N1血凝素重链可变区-人IgGFc段嵌合抗体的制备和鉴定

    Institute of Scientific and Technical Information of China (English)

    夏立亮; 吴标; 程亚庭; 蔡家麟; 王颖; 赵国屏

    2012-01-01

    To prepare and characterize llama variable domain of heavy chain of heavy-chain antibody-human IgGlFc (VHH-hFc) chimeric antibody against hemagglutinin from H5N1 avian influenza virus, recombinant expression vector pET-22b-VHH23-hFc was constructed and VHH23-hFc chimeric antibody was expressed in E. coli BL2KDE3) strain by IPTG induction. As VHH23-hFc antibody was accumulated in inclusion bodies, two different refolding methods, dialysis and on-column refolding, were compared for the refolding efficacy and the optimal method was adopted for preparation of VHH23-hFc chimeric antibody. The activity and thermal stability of VHH antibodies were tested by ELISA. By using dialysis refolding procedure, VHH23-hFc chimeric antibody has been obtained with higher yield and good quality. The affinity constant of VHH23-hFc chimeric antibody was 2. 24 × 106 mol/L as determined by ELISA. VHH23-hFc chimeric antibody also displayed good thermal stability. The half-life span of VHH23-hFc chimeric antibody in mice was up to 35 hrs, which is comparable to conventional chimeric antibodies. Taken together, our results indicated that VHH23-hFc chimeric antibody against hemagglutinin derived from H5N1 avian influenza virus has been obtained with high activity, good thermal stability as well as longer half-life span, which provides basis for future functional study both in vitro and in vivo.%本研究旨在制备羊驼抗H5N1禽流感病毒的重链抗体可变区-人Fc段嵌合体抗体制备,对所得嵌合抗体进行制备和功能鉴定,为临床应用奠定基础.用pET-22b表达载体构建抗H5N1禽流感病毒羊驼重链可变区(VHH)-人IgG1Fc嵌合基因,以包涵体形式表达VHH23-hFc嵌合抗体蛋白,采用优化的方法复性后,获得高纯度VHH23-hFc嵌合抗体,用ELISA法鉴定嵌合抗体亲和力、热稳定性和小鼠体内的半衰期.结果显示,透析复性后原核表达的抗H5N1禽流感病毒VHH23-hFc嵌合抗体亲和力为2.24×106 mol/L,具有较好

  8. Husbandry Practices and Outbreak Features of Natural Highly Pathogenic Avian Influenza H5N1 in Turkey Flocks in Nigeria 2006-2008

    OpenAIRE

    Olatunde Babatunde Akanbi; Victor Olusegun Taiwo

    2015-01-01

    The Highly Pathogenic Avian Influenza (HPAI) outbreaks in Nigeria that occurred during 2006-2008, affected 80 farms that kept subsistence indigenous chicken, duck, turkey, guinea fowl and geese in 15 states of the country including the capital, Abuja resulting in a total loss of more than 14,000 birds in backyard, semi-intensive or free-ranged flocks. The rearing of rural poultry in free-range, multispecies, multiage holdings that have low biosecurity levels have shown to expose them to many ...

  9. Hemagglutinin protein of avian influenza virus H5N1 in immune injury of peripheral immune organs and its possible mechanism%H5N1病毒HA蛋白对小鼠外周免疫器官的损伤及其机制

    Institute of Scientific and Technical Information of China (English)

    葛南海; 胥韦; 陈敏惠; 徐军

    2012-01-01

    This study aims to investigate the role of recombinant hemagglutinin protein (HA) of avian influenza virus (AVI) H5N1 in immune injury of peripheral immune organ spleen and the related cytokines secretion in mice. By using insect-baculovirus expression system and nickel affinity magnet beads, HA protein of AVI H5N1 was recombined and was used in mice. Seventy-two hours after HA protein instillation, the lungs and spleens were isolated form the mice. Pathological examination revealed spleen swelling, destruction of local structure of germinal center, vacuolar changes and a decrease in lymphocyte, while lung pathological examination showed diffuse alveolar damage, inflammatory cell infiltration in mice challenged by HA. The injury index of spleen cells after LPS stimulation in HA pretreatment was higher than that in those of PBS pretreatment. And under basal condition, the levels of IP-10, MCP-la and Rantes released from the spleen cells of mice in HA pretreatment were significantly higher than those from the mice of PBS pretreatment group (P< 0.05). Twenty-four hours after LPS stimulation, the levels of IFN-γ, IP-10, MCP-la, and Rantes released from the spleen cells of HA pre-treated mice was significantly higher than those from PBS pretreated mice (P< 0.05). In conclusion, the H5N1 virus HA membrane protein by intratracheal instillation elicits a strong pathological immune response in the host, resulting in immune injury of peripheral lymphoid organs and immune cells and acute lung injury.%目的 研究H5N1病毒HA蛋白作用于小鼠后对其外周免疫器官脾脏的损伤其相关细胞因子的分泌.方法 通过昆虫-杆状病毒表达系统表达H5N1病毒HA蛋白,并经镍亲和磁珠纯化,将重组的HA蛋白作用于小鼠,72 h后,取其脾脏,观察其镜下形态学变化;分离脾细胞并培养,检测其细胞因子的分泌.结果 脾组织病理表现为局部性弥漫性肺泡损伤,单核细胞侵润,脾脏肿胀,毛细血管充血,生发

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

    International Nuclear Information System (INIS)

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

  11. 人感染高致病性禽流感A/H5N1研究现状%Current opinions in highly pathogenic avian influenza A/HSN1 infection in human being

    Institute of Scientific and Technical Information of China (English)

    李佳; 高占成

    2009-01-01

    The avian influenza virus A/HSN1, known to infect only birds previously, broke the species-interface to infect human beings in Hong Kong in 1997. In the 21st century,highly pathogenic avian influenza viruse A/H5N1 is unprecedently spreading to the continents of Asia, Middle East and Africa, involving 15 countries. The mortality is over 60% and this incidence raises universally,concerning about the possibility that such an influenza virus might become the next influenza pandemic strain. This review summarizes the current opinions of avian influenza A/H5N1 with emphasis on virology, epidemiology, pathology and pathogenesis.%1997年,在香港发生禽流感病毒A/HSNl首次突破种间屏障感染人类的病例.21世纪以来,A/HSN1亚型高致病性禽流感疫情的传播范围、规模以及蔓延速度达到了前所未有的程度.世界上许多国家受到冲击,世界范围内病死率超过60%.鉴于目前全球可能出现新一次流感大流行的严峻形势,加强人禽流感的研究迫在眉睫.本文就人禽流感的病毒研究、流行病学特征、病理改变、发病机制等方面进展进行简要综述.

  12. 禽流感病毒H5N1血凝素蛋白的细胞膜上提纯和结晶%Purification and crystallization of hemagglutinin expressed on the cellular membrane originated from avian influenza virus H5N1

    Institute of Scientific and Technical Information of China (English)

    谌资; 郑煜煌; Yipu Lin; David J Stevens; Steve A Wharton; Patrick J Collins; Junfeng Liu; Alan J Hay

    2009-01-01

    目的 从细胞膜上提纯禽流感病毒H5N1的血凝素蛋白H5 I151F和H5 I151F+A134V+E186D,并使蛋白结晶.方法 细胞内大量增殖重组牛痘病毒,去垢剂提取细胞膜中的HA蛋白,连续蔗糖密度梯度超速离心,Western印迹检测,菠萝蛋白酶等裂解HA,离子交换层析,SDS-PAGE电泳并染色检测蛋白纯度,坐滴气象扩散法结晶.结果 从细胞膜中提取了高纯度的血凝素蛋白H5 I151F和H5 I151F+A134V+E186D,并得到了H5 I151F蛋白晶体.结论 首次获得了禽流感病毒H5N1的H5 I151F蛋白晶体,为进一步研究禽流感病毒人传人的可能性打下基础.%Objective To purify and crystallize two kinds of H5N1 vires hemagglutinin proteins, H5 I151F and H5 I151F + A134V + E186D, from the cellular membrane. Methods Recombinant vaccinia viruses were massive propagated, hemagglutinin (HA) proteins were extracted from cellular membrane with detergent. HA proteins were concentrated with continuous sucrose gradient ultracentrifugation and detected by Western Blotting. HA proteins were cleavaged with Bromelain, and purified with Ion-exchange chromatography. The protein puri-ty was detected by SDS-PAGE electrophoresis and staining. HA proteins were crystallized by sitting-drop vapour diffusion. Results Hemag-glutinin proteins, H5 I151F and H5 I151F + A134V + E186D, were extensively purified. And the crystal of H5 I151F was obtained. Con-clusion For the first time, the highly purified H5 I151F membrane protein crystal was obtained, which provided the basis for further stud-ying the mechanisms of human to human transmission caused by avian influenza viruses.

  13. 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.

  14. 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

    目的 设计并获得一种安全、高效,并能对以H5N1亚型为主的多种禽流感病毒亚型产生保护的复合基因工程疫苗.方法 利用分子生物学和分子免疫学方法对国内以及周边国家流行的禽流感毒株进行全面分析,利用生物信息学技术合理设计亚单位加表位的全新复合结构疫苗的氨基酸序列;利用大肠杆菌密码子优化技术根据疫苗氨基酸序列获得基因序列;通过全基因合成的方法获得该疫苗的基因,并通过大肠杆菌表达系统对该疫苗进行表达;目的蛋白经过包涵体洗涤和色谱纯化后复性;通过ELISA评价其抗原特异性,并乳化制备成禽流感蛋白疫苗,通过小鼠体内免疫试验检测其免疫效力.结果 设计了包含通用性的辅助性T细胞表位、B细胞表位以及CTL表位的串接疫苗结构;全基因合成获得了该复合疫苗的基因序列;该基因在大肠杆菌表达系统中得到了高效表达,目的蛋白表达量约占菌体总蛋白30%;经过粗纯和精纯后的目的蛋白纯度达到95.5%,复性后获得可溶性蛋白溶液,浓度可达2.4 mg/mL.结论 通过小鼠实验,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.小鼠免疫试验证明,该疫苗可以在小鼠体内有效诱发免疫应答.%Objective To design and prepare a genetic engineering vaccine against avian influenza virus H5N1. Methods The composite amino acid sequences plus epitope subunit of vaccine were designed based on the analysis of prevalent avian influenza H5N1 strains and bioinformatics. The amino acid sequence was obtained with E. Coli codon optimization technique; the vaccine gene was synthesized with the whole gene synthesis method and expressed with E. Coli expression system. Theprotein inclusion bodies were purified by renaturation chromatography after washing; the antigen specificity was

  15. Screening of Proteins Interacting with Nonstructural 1 Protein of H5N1 Avian Influenza Virus from T7-phage Display Library

    Institute of Scientific and Technical Information of China (English)

    ZHU Chun-yu; WU Jian-guo; LIU Hong-sheng; SUN Ting-ting; ZHAO Jian; WANG Ning; ZHENG Fang-liang; AI Hai-xin; ZHU Jun-feng; WANG Xiao-ying; ZHU Ying

    2012-01-01

    Avian influenza virus(AIV) nonstructural 1(NS1) gene was amplified by real-time polymerse chain reaction(RT-PCR) and inserted into pET28a,then transformed into E.coli BL21(DE3) competent cell.With the induction of isopropyl-β-D-thiogalactoside(IPTG) and the purification of Ni-NTA column,we finally obtained purified NS1 protein.T7-phage display system was used to screen the proteins that interacted with NS1 from lung cell cDNA library.The selected positive clones were identified by DNA sequencing and analyzed by BLAST program in GeneBank.Two proteins were obtained as NS 1 binding proteins,Homo sapiens nucleolar and coiled-body phosphoprotein 1(NOLC1) and Homo sapiens similar to colon cancer-associated antigen.By co-immunoprecipitation and other methods,Homo sapiens NOLC1 was found to interact with the NS1 protein,the results would provide the basis for further studying biological function of NS1 protein.

  16. The significance of naturally occurring neuraminidase quasispecies of H5N1 avian influenza virus on resistance to oseltamivir: a point of concern.

    Science.gov (United States)

    Schaduangrat, Nalini; Phanich, Jiraphorn; Rungrotmongkol, Thanyada; Lerdsamran, Hatairat; Puthavathana, Pilaipan; Ubol, Sukathida

    2016-06-01

    Viral adaptability and survival arise due to the presence of quasispecies populations that are able to escape the immune response or produce drug-resistant variants. However, the presence of H5N1 virus with natural mutations acquired without any drug selection pressure poses a great threat. Cloacal samples collected from the 2004-2005 epidemics in Thailand from Asian open-billed storks revealed one major and several minor quasispecies populations with mutations on the oseltamivir (OTV)-binding site of the neuraminidase gene (NA) without prior exposure to a drug. Therefore, this study investigated the binding between the NA-containing novel mutations and OTV drug using molecular dynamic simulations and plaque inhibition assay. The results revealed that the mutant populations, S236F mutant, S236F/C278Y mutant, A250V/V266A/P271H/G285S mutant and C278Y mutant, had a lower binding affinity with OTV as compared with the WT virus due to rearrangement of amino acid residues and increased flexibility in the 150-loop. This result was further emphasized through the IC50 values obtained for the major population and WT virus, 104.74 nM and 18.30 nM, respectively. Taken together, these data suggest that H5N1 viruses isolated from wild birds have already acquired OTV-resistant point mutations without any exposure to a drug. PMID:26935590

  17. Reverse genetics based rgH5N2 vaccine provides protection against high dose challenge of H5N1 avian influenza virus in chicken.

    Science.gov (United States)

    Bhatia, S; Khandia, R; Sood, R; Bhat, S; Siddiqui, A; Jahagirdhar, G; Mishra, S; Mishra, A; Pateriya, A K; Kulkarni, D D

    2016-08-01

    An inactivated vaccine was developed using the rgH5N2 virus (6 + 2 reassortant) generated by plasmid based reverse genetics system (RGS) with WSN/33/H1N1 as backbone virus. Following mutation of the basic amino acid cleavage site RRRKKR*GLF to IETR*GLF, the H5-HA (haemagglutinin) gene of the selected donor H5N1 virus (A/chicken/West Bengal/80995/2008) of antigenic clade 2.2 was used along with the N2-NA gene from H9N2 field isolate (A/chicken/Uttar Pradesh/2543/2004) for generation of the rgH5N2 virus. A single dose (0.5 ml/bird) of the inactivated rgH5N2 vaccine protected 100% of the vaccinated chickens (n = 10) on 28(th) dpv (early challenge) and 90% of the vaccinated chickens (n = 10) on 200(th) dpv (late challenge) against high dose challenge with HPAI virus (10(9) EID50/bird). Challenge virus shedding via oropharynx and cloaca of the vaccinated chickens was detectable by realtime RT-PCR during 1-5 dpc and 1-9 days dpc in the early and the late challenge, respectively. The protective level of antibodies (mean HI titre > 128) was maintained without booster vaccination for 200 days. The present study provides the experimental evidence about the extent of protection provided by a reverse genetics based vaccine for clade 2.2 H5N1 viruses against challenge with high dose of field virus at two different time points (28 dpv and 200 dpv). The challenge study is uniquely different from the previous similar experiments on account of 1000 times higher dose of challenge and protection at 200 dpv. The protection and virus shedding data of the study may be useful for countries planning to use H5 vaccine in poultry especially against the clade 2.2 H5N1 viruses. PMID:27296706

  18. Husbandry Practices and Outbreak Features of Natural Highly Pathogenic Avian Influenza H5N1 in Turkey Flocks in Nigeria 2006-2008

    Directory of Open Access Journals (Sweden)

    Olatunde Babatunde Akanbi

    2015-12-01

    Full Text Available The Highly Pathogenic Avian Influenza (HPAI outbreaks in Nigeria that occurred during 2006-2008, affected 80 farms that kept subsistence indigenous chicken, duck, turkey, guinea fowl and geese in 15 states of the country including the capital, Abuja resulting in a total loss of more than 14,000 birds in backyard, semi-intensive or free-ranged flocks. The rearing of rural poultry in free-range, multispecies, multiage holdings that have low biosecurity levels have shown to expose them to many contact risks. In order to sustain turkey production in the country in view of the ongoing resurgent HPAI outbreaks, it is necessary to assess the impact of HPAI on this species and to evaluate the husbandry and outbreak features of affected flocks. Spatial data confirmed the presence of HPAI virus in both domestic and commercial poultry farms from 25 States and the Federal Capital Territory (FCT in Nigeria were added to a Geographical Information System (GIS using ESRI ArcGIS 10.3 (ESRI®, USA and QGIS 2.8.2 Desktop (OSGeo and visualized using QGIS. Post mortem examinations of submitted carcasses were carried out and swabs and tissues were analyzed by virus isolation (VI and reverse transcriptase polymerase chain reaction (RT-PCR. HPAI in turkey flocks were mostly in northern part of the country where most poultry mainly subsistence are domiciled and are more in the densely cities of the north. The poultry management systems employed by the subsistence turkey farmers were mainly semi-intensive backyard and free-ranged system of poultry. HPAI introduction sources vary from the introduction of new poultry species (geese and turkey from LBM, to the death of neighborhood poultry and extension to turkey flocks and/or contact with free-ranging local chickens. It is obvious that the husbandry and the management system had influenced on the introduction of the virus and the course of the disease.

  19. PA-X-associated early alleviation of the acute lung injury contributes to the attenuation of a highly pathogenic H5N1 avian influenza virus in mice.

    Science.gov (United States)

    Hu, Jiao; Mo, Yiqun; Gao, Zhao; Wang, Xiaoquan; Gu, Min; Liang, Yanyan; Cheng, Xin; Hu, Shunlin; Liu, Wenbo; Liu, Huimou; Chen, Sujuan; Liu, Xiaowen; Peng, Daxing; Liu, Xiufan

    2016-08-01

    PA-X is a novel discovered accessory protein encoded by the PA mRNA. Our previous study demonstrated that PA-X decreases the virulence of a highly pathogenic H5N1 strain A/Chicken/Jiangsu/k0402/2010 in mice. However, the underlying mechanism of virulence attenuation associated with PA-X is still unknown. In this study, we compared two PA-X-deficient mutant viruses and the parental virus in terms of induction of pathology and manipulation of host response in the mouse lung, stimulation of cell death and PA nuclear accumulation. We first found that down-regulated PA-X expression markedly aggravated the acute lung injury of the infected mice early on day 1 post-infection (p.i.). We then determined that loss of PA-X expression induced higher levels of cytokines, chemokines and complement-derived peptides (C3a and C5a) in the lung, especially at early time point's p.i. In addition, in vitro assays showed that the PA-X-deficient viruses enhanced cell death and increased expression of reactive oxygen species (ROS) in mammalian cells. Moreover, we also found that PA nuclear accumulation of the PA-X-null viruses accelerated in MDCK cells. These results demonstrate that PA-X decreases the level of complement components, ROS, cell death and inflammatory response, which may together contribute to the alleviated lung injury and the attenuation of the virulence of H5N1 virus in mice.

  20. PA-X-associated early alleviation of the acute lung injury contributes to the attenuation of a highly pathogenic H5N1 avian influenza virus in mice.

    Science.gov (United States)

    Hu, Jiao; Mo, Yiqun; Gao, Zhao; Wang, Xiaoquan; Gu, Min; Liang, Yanyan; Cheng, Xin; Hu, Shunlin; Liu, Wenbo; Liu, Huimou; Chen, Sujuan; Liu, Xiaowen; Peng, Daxing; Liu, Xiufan

    2016-08-01

    PA-X is a novel discovered accessory protein encoded by the PA mRNA. Our previous study demonstrated that PA-X decreases the virulence of a highly pathogenic H5N1 strain A/Chicken/Jiangsu/k0402/2010 in mice. However, the underlying mechanism of virulence attenuation associated with PA-X is still unknown. In this study, we compared two PA-X-deficient mutant viruses and the parental virus in terms of induction of pathology and manipulation of host response in the mouse lung, stimulation of cell death and PA nuclear accumulation. We first found that down-regulated PA-X expression markedly aggravated the acute lung injury of the infected mice early on day 1 post-infection (p.i.). We then determined that loss of PA-X expression induced higher levels of cytokines, chemokines and complement-derived peptides (C3a and C5a) in the lung, especially at early time point's p.i. In addition, in vitro assays showed that the PA-X-deficient viruses enhanced cell death and increased expression of reactive oxygen species (ROS) in mammalian cells. Moreover, we also found that PA nuclear accumulation of the PA-X-null viruses accelerated in MDCK cells. These results demonstrate that PA-X decreases the level of complement components, ROS, cell death and inflammatory response, which may together contribute to the alleviated lung injury and the attenuation of the virulence of H5N1 virus in mice. PMID:27289459

  1. Pathology of Chicken Experimentally Infected with a Avian Influenza Virus,A/goose/Guangdong/2/1996 (H5N1)%一株鹅源H5N1亚型禽流感病毒人工感染鸡的理学研究

    Institute of Scientific and Technical Information of China (English)

    叶远兰; 刘启宏; 李玉谷

    2012-01-01

    鸡肌肉接种鹅源禽流感病毒A/goose/Guangdong/2/1996 (H5N1)后,引起约70%发病率和60%死亡率,并表现出一些显微和超微病理学变化,主要为全身性充血、淤血、出血和血栓形成,多种器官的细胞变性、坏死、炎症,以及胰腺、肾脏、肝脏、心脏、肺脏、脑、肠、胸腺、脾脏、法氏囊等的细胞凋亡.%Chickens intramuscularly inoculated with a avian influenza virus, A/goose/Guangdong/2/1996(H5Nl) .produced approximately 70% of morbidity and 60% of mortality, and had micropathological and ultrapathological lessions in some degree in multiple organs,such as, systemic hyperemia, congestion, haemorrhage, thrombosis, and cell degeneration,necrosis,and inflammation etc. As well as apoptosis was detected in pancreas, kidney, liver, heart, lung, cerebrum, intestines, thymus, spleen and bursa of fabricius etc.

  2. Knowledge, attitudes and practices towards avian influenza A (H5N1) among Cambodian women:A cross-sectional study

    Institute of Scientific and Technical Information of China (English)

    Mav Khun; Chantha Heng; Md Harun-Or-Rashid; Hideki Kasuya; Junichi Sakamoto

    2012-01-01

    Objective:To measure highly pathogenic avian influenza(HPAI)-related knowledge, attitudes, and practices(KAPs) amongCambodian women.Methods:This cross-sectional study selected 246 married women aged between18-55 years who had backyard poultry and lived at least one year in the areas of the survey through multi-stage cluster sampling.An average score of correct answers was generated to evaluate respondents’ knowledge(Good/Poor), attitudes(Positive/Negative), and practices(Good/Bad).Results:We reported that about half of the respondents had good knowledge and good practices and four-fifth of them had positive attitudes towards HPAI.Odds ratios(ORs) and95% confidence intervals(CIs) were estimated through a logistic regression model to explore contributing factors that raise theirKAP levels.Most ofthe sources were significant in increasing knowledge of the respondent, like television(OR=1.6,95%CI=1.0-2.7), radio(OR=2.5,95%CI=1.3-4.9), leaflets/booklets(OR=2.1,95%CI=1.2-3.9), school students (OR=18.4,95%CI=2.4-142.9), village health volunteers(OR=4.5,95%CI=2.2-10.9)etc.Factors such as television(OR=3.7,95%CI=2.1-6.4), leaflets/booklets(OR=2.6,95%CI=1.4-5.1), and public health staff(OR=2.2,95%CI=1.2-4.1) had similar influence on practices.Although, we found similar effect on raising the attitudes of the responded, it was not significant.Conclusions:We report a satisfactory level of positive attitudes, and moderate level of knowledge and practices related toHPAI amongCambodian women.RaisingKAPs through television, radio and other medias may be more efficient than using usual information, education and communication materials to preventHPAI.

  3. 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...

  4. Characterization of Clade 2.3.2.1 H5N1 Highly Pathogenic Avian Influenza Viruses Isolated from Wild Birds (Mandarin Duck and Eurasian Eagle Owl in 2010 in Korea

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    Youn-Jeong Lee

    2013-04-01

    Full Text Available Starting in late November 2010, the H5N1 highly pathogenic avian influenza (HPAI virus was isolated from many types of wild ducks and raptors and was subsequently isolated from poultry in Korea. We assessed the genetic and pathogenic properties of the HPAI viruses isolated from a fecal sample from a mandarin duck and a dead Eurasian eagle owl, the most affected wild bird species during the 2010/2011 HPAI outbreak in Korea. These viruses have similar genetic backgrounds and exhibited the highest genetic similarity with recent Eurasian clade 2.3.2.1 HPAI viruses. In animal inoculation experiments, regardless of their originating hosts, the two Korean isolates produced highly pathogenic characteristics in chickens, ducks and mice without pre-adaptation. These results raise concerns about veterinary and public health. Surveillance of wild birds could provide a good early warning signal for possible HPAI infection in poultry as well as in humans.

  5. 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.

  6. 温度和时间对血凝试验测定禽流感病毒H5N1亚型Re-6株抗原效价的影响%Effects of Temperature and Time on the Antigen Titer of H5N1 Subtype of Avian Influenza Re-6 Strain by Hemagglutination Test

    Institute of Scientific and Technical Information of China (English)

    赵明娟; 赵俊永

    2014-01-01

    旨在研究不同温度和反应时间对血凝试验测定禽流感病毒H5N1亚型Re-6株抗原效价的影响。试验设定4、25、37℃3个温度,分别读取反应5、10、15、20、25、30、35、40、45、50、55、60 min时的抗原效价。结果表明,随着反应温度的升高,试验结果出现时间缩短。4℃反应25 min结果趋于稳定,反应50 min时开始解凝;25℃反应20 min结果趋于稳定,反应40 min时开始解凝;37℃反应15 min结果趋于稳定,反应30 min时开始解凝。%The research aimed to study the effects of different temperature and reaction time on the antigen titer of H5N1 subtype of avian influenza Re-6 strain determined by hemagglutination test. Three temperatures (4, 25 and 37℃) were set to read the titers after reacting 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 and 60 min respectively. The results showed that the the appearance time of result was shortened with the increase of reaction temperature. The results tended to be stable after reacting at 4℃for 25 min and deflocculation started after reacting 50 min. The results tended to be stable after reacting at 25 ℃ for 20 min and deflocculation started after reacting 40 min. The results tended to be stable after reacting at 37 ℃for 15 min and deflocculation started after reacting 30 min.

  7. 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. PMID:23820377

  8. 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.

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

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    Yuen Kit M

    2009-10-01

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

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

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    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.

  11. 动物园鹦鹉科鸟类H5 N1禽流感疫苗免疫后效果监测%Immune Effect Monitoring of H5N1 Type Avian Influenza for Some Species of Captive Psittacid Birds

    Institute of Scientific and Technical Information of China (English)

    李莹; 吴秀山; 张成林; 张金国

    2012-01-01

    Over the years,captive birds of Beijing Zoo were given the AIV vaccine immunization in strict accordance with government mandate.But the immune effects of different bird species after vaccination have not been studied.The purpose of this study was to explore the immune effects of commercial avian influenza vaccine in birds and the immune response of different species to the vaccines.Species of captive psittacid birds were selected for study.Birds were immunized with avian influenza H5N1 subtype vaccine.We then used the test of hemagglutinin(HA)and hemagglutination inhibition(HI)to monitor antibody levels and to assess immune effects.Birds immunized only one time generally showed low immune response,i.e.the immune effect was not ideal.Based on this result,we chose Budgerigar(Melopsittacus undulatus)for further study in which we adjusted the immunization procedure to gain better immune effects.This provided a scientific basis for developing immunization procedures for other species of wild birds.%多年来动物园虽然严格按照国家强制要求对园内饲养的野生鸟类进行禽流感疫苗的免疫接种工作,但是对于接种后各种鸟类免疫效果的问题仍未有研究。本次研究主要目的为探究圈养鸟类免疫商品化禽流感疫苗后的免疫效果如何,以及各个物种对疫苗的免疫应答水平是否相同。实验中选取动物园几种圈养小型鹦鹉科鸟类为实验对象,对其进行禽流感H5N1亚型疫苗免疫接种后,利用血凝(HA)及血凝抑制(HI)实验监测禽流感抗体水平变化规律,评估免疫效果。从初步的实验结果发现,鹦鹉科鸟类仅接种一次商品化禽流感疫苗,其免疫应答水平普遍偏低,免疫效果不理想。根据实验结果,尝试性地以虎皮鹦鹉为实验对象,尝试调整免疫程序后再次进行禽流感疫苗的免疫接种,通过多次尝试找出较好的免疫程序,使得虎皮鹦鹉的禽流感疫苗免疫效果得到

  12. 人感染高致病性禽流感病毒H5N1的病理学和病原学特点%Histologic and ultrastructural studies of the patient died of highly pathogenic H5N1 avian influenza virus infection in China

    Institute of Scientific and Technical Information of China (English)

    李宁; 祝庆余; 余琦; 王巍; 王一平

    2008-01-01

    Objective To explore histopathologic and ultrastructural characteristics of human avian influenza (AI) infection and related etiological pathogenesis.Methods Postmortem lung and heart samples were collected from the patient who died of avian influenza virus infection on November 29,2003 in China.Light and electron microscopy,immunohistochemistry and histochemistry were used to investigate the pathological changes.Results The main pathological findings included extensive pulmonary consolidation,hemorrhage,pulmonary edema and local hemorrhagic infarct.The lamina of alveoli and bronchioles were abundantly filled with protein-rich fluid,erythrocytes,fibrin and cell debris admixed with many neutrophilis.macrophages,lymphocytes and a few of monokaryon and multinuclear giant cells.Hyaline membranes were formed.Local pulmonary tissues were heavily damaged by hemorrhage and necrosis.Alveolar septum was disintegrated.Mesenchymal edema with a few of macrophages infiltration of heart was found.Electron microscopy showed the avian influenza A virus-like particles (type C and type A) of 80~120 nm diameter and envelopes in the cytoplasm of pneumocytes and endothelial cells.Conclusions Fatal pneumonia associated with highly pathogenic avian influenza A virus (H5N1) infection leads to extensive pulmonary consolidation,edema and marked hemorrhagic necrosis and inflammation.Electron microscopy can identify avian influenza A virus-like particles.The findings may offer an important theoretical basis for clinical diagnosis and treatment.%目的 探讨人感染禽流行性感冒病毒的病理学及病原学特点.方法 应用透射电镜、光镜、组织化学和免疫组织化学方法对发生在2003年11月中国内地人禽流感死亡尸检病例1例进行观察研究.行病原体分离培养鉴定、全基因组序列测定和动物致病性观察以确定病原学特点.结果 肺部病理改变主要表现为广泛性肺实变,肺出血、肺水肿及坏死.肺泡腔内充

  13. Role of position 627 of PB2 and the multibasic cleavage site of the hemagglutinin in the virulence of H5N1 avian influenza virus in chickens and ducks.

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    Karel A Schat

    Full Text Available Highly pathogenic H5N1 avian influenza viruses have caused major disease outbreaks in domestic and free-living birds with transmission to humans resulting in 59% mortality amongst 564 cases. The mutation of the amino acid at position 627 of the viral polymerase basic-2 protein (PB2 from glutamic acid (E in avian isolates to lysine (K in human isolates is frequently found, but it is not known if this change affects the fitness and pathogenicity of the virus in birds. We show here that horizontal transmission of A/Vietnam/1203/2004 H5N1 (VN/1203 virus in chickens and ducks was not affected by the change of K to E at PB2-627. All chickens died between 21 to 48 hours post infection (pi, while 70% of the ducks survived infection. Virus replication was detected in chickens within 12 hours pi and reached peak titers in spleen, lung and brain between 18 to 24 hours for both viruses. Viral antigen in chickens was predominantly in the endothelium, while in ducks it was present in multiple cell types, including neurons, myocardium, skeletal muscle and connective tissues. Virus replicated to a high titer in chicken thrombocytes and caused upregulation of TLR3 and several cell adhesion molecules, which may explain the rapid virus dissemination and location of viral antigen in endothelium. Virus replication in ducks reached peak values between 2 and 4 days pi in spleen, lung and brain tissues and in contrast to infection in chickens, thrombocytes were not involved. In addition, infection of chickens with low pathogenic VN/1203 caused neuropathology, with E at position PB2-627 causing significantly higher infection rates than K, indicating that it enhances virulence in chickens.

  14. 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.

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

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    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

  16. Avian influenza

    Science.gov (United States)

    Bird flu; H5N1; H5N2; H5N8; H7N9; Avian influenza A (HPAI) H5 ... The first avian influenza in humans was reported in Hong Kong in 1997. It was called avian influenza (H5N1). The outbreak was linked ...

  17. 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. PMID:27068161

  18. 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. PMID:26976597

  19. Evolutionary and transmission dynamics of reassortant H5N1 influenza virus in Indonesia.

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    Tommy Tsan-Yuk Lam

    Full Text Available H5N1 highly pathogenic avian influenza (HPAI viruses have seriously affected the Asian poultry industry since their recurrence in 2003. The viruses pose a threat of emergence of a global pandemic influenza through point mutation or reassortment leading to a strain that can effectively transmit among humans. In this study, we present phylogenetic evidences for the interlineage reassortment among H5N1 HPAI viruses isolated from humans, cats, and birds in Indonesia, and identify the potential genetic parents of the reassorted genome segments. Parsimony analyses of viral phylogeography suggest that the reassortant viruses may have originated from greater Jakarta and surroundings, and subsequently spread to other regions in the West Java province. In addition, Bayesian methods were used to elucidate the genetic diversity dynamics of the reassortant strain and one of its genetic parents, which revealed a more rapid initial growth of genetic diversity in the reassortant viruses relative to their genetic parent. These results demonstrate that interlineage exchange of genetic information may play a pivotal role in determining viral genetic diversity in a focal population. Moreover, our study also revealed significantly stronger diversifying selection on the M1 and PB2 genes in the lineages preceding and subsequent to the emergence of the reassortant viruses, respectively. We discuss how the corresponding mutations might drive the adaptation and onward transmission of the newly formed reassortant viruses.

  20. Anti-viral properties and mode of action of standardized Echinacea purpurea extract against highly pathogenic avian Influenza virus (H5N1, H7N7 and swine-origin H1N1 (S-OIV

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    Schoop Roland

    2009-11-01

    Full Text Available Abstract Background Influenza virus (IV infections are a major threat to human welfare and animal health worldwide. Anti-viral therapy includes vaccines and a few anti-viral drugs. However vaccines are not always available in time, as demonstrated by the emergence of the new 2009 H1N1-type pandemic strain of swine origin (S-OIV in April 2009, and the acquisition of resistance to neuraminidase inhibitors such as Tamiflu® (oseltamivir is a potential problem. Therefore the prospects for the control of IV by existing anti-viral drugs are limited. As an alternative approach to the common anti-virals we studied in more detail a commercial standardized extract of the widely used herb Echinacea purpurea (Echinaforce®, EF in order to elucidate the nature of its anti-IV activity. Results Human H1N1-type IV, highly pathogenic avian IV (HPAIV of the H5- and H7-types, as well as swine origin IV (S-OIV, H1N1, were all inactivated in cell culture assays by the EF preparation at concentrations ranging from the recommended dose for oral consumption to several orders of magnitude lower. Detailed studies with the H5N1 HPAIV strain indicated that direct contact between EF and virus was required, prior to infection, in order to obtain maximum inhibition in virus replication. Hemagglutination assays showed that the extract inhibited the receptor binding activity of the virus, suggesting that the extract interferes with the viral entry into cells. In sequential passage studies under treatment in cell culture with the H5N1 virus no EF-resistant variants emerged, in contrast to Tamiflu®, which produced resistant viruses upon passaging. Furthermore, the Tamiflu®-resistant virus was just as susceptible to EF as the wild type virus. Conclusion As a result of these investigations, we believe that this standard Echinacea preparation, used at the recommended dose for oral consumption, could be a useful, readily available and affordable addition to existing control options

  1. 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.

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

    Directory of Open Access Journals (Sweden)

    Yu-Fen Tseng

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

  3. Bayesian Inference Reveals Host-Specific Contributions to the Epidemic Expansion of Influenza A H5N1.

    Science.gov (United States)

    Trovão, Nídia Sequeira; Suchard, Marc A; Baele, Guy; Gilbert, Marius; Lemey, Philippe

    2015-12-01

    Since its first isolation in 1996 in Guangdong, China, the highly pathogenic avian influenza virus (HPAIV) H5N1 has circulated in avian hosts for almost two decades and spread to more than 60 countries worldwide. The role of different avian hosts and the domestic-wild bird interface has been critical in shaping the complex HPAIV H5N1 disease ecology, but remains difficult to ascertain. To shed light on the large-scale H5N1 transmission patterns and disentangle the contributions of different avian hosts on the tempo and mode of HPAIV H5N1 dispersal, we apply Bayesian evolutionary inference techniques to comprehensive sets of hemagglutinin and neuraminidase gene sequences sampled between 1996 and 2011 throughout Asia and Russia. Our analyses demonstrate that the large-scale H5N1 transmission dynamics are structured according to different avian flyways, and that the incursion of the Central Asian flyway specifically was driven by Anatidae hosts coinciding with rapid rate of spread and an epidemic wavefront acceleration. This also resulted in long-distance dispersal that is likely to be explained by wild bird migration. We identify a significant degree of asymmetry in the large-scale transmission dynamics between Anatidae and Phasianidae, with the latter largely representing poultry as an evolutionary sink. A joint analysis of host dynamics and continuous spatial diffusion demonstrates that the rate of viral dispersal and host diffusivity is significantly higher for Anatidae compared with Phasianidae. These findings complement risk modeling studies and satellite tracking of wild birds in demonstrating a continental-scale structuring into areas of H5N1 persistence that are connected through migratory waterfowl.

  4. Mammalian-transmissible H5N1 influenza: facts and perspective.

    Science.gov (United States)

    Osterholm, Michael T; Kelley, Nicholas S

    2012-01-01

    Two recently submitted (but as yet unpublished) studies describe success in creating mutant isolates of H5N1 influenza A virus that can be transmitted via the respiratory route between ferrets; concern has been raised regarding human-to-human transmissibility of these or similar laboratory-generated influenza viruses. Furthermore, the potential release of methods used in these studies has engendered a great deal of controversy around publishing potential dual-use data and also has served as a catalyst for debates around the true case-fatality rate of H5N1 influenza and the capability of influenza vaccines and antivirals to impact any future unintentional or intentional release of H5N1 virus. In this report, we review available seroepidemiology data for H5N1 infection and discuss how case-finding strategies may influence the overall case-fatality rate reported by the WHO. We also provide information supporting the position that if an H5N1 influenza pandemic occurred, available medical countermeasures would have limited impact on the associated morbidity and mortality. PMID:22366820

  5. A Electrochemical Immunosensor Detection of Avian Influenza Virus (H5N1) Based on Nano Materials%基于纳米材料的电化学免疫传感器检测HSN1亚型禽流感病毒的研究

    Institute of Scientific and Technical Information of China (English)

    黄娇玲; 谢芝勋; 罗思思; 谢志勤; 谢丽基; 刘加波; 庞耀珊; 范晴

    2013-01-01

    利用氧化石墨烯(GO)负载H5N1亚型禽流感病毒多克隆抗体(PAb-H5N1)及牛血清白蛋白(BSA)作为信号放大材料,构建一种新型电化学免疫传感器用于检测H5N1亚型禽流感病毒.结果表明:以PAb-H5N1-GOBSA纳米复合物作为信号放大材料构建的电化学免疫传感器的灵敏度比不用此纳米复合物作为信号放大的高256倍.以PAb-H5N1-GO-BSA纳米复合物作为信号放大材料构建的电化学免疫传感器对H5N1亚型禽流感病毒的检测限为2-15HA unit·50μL-1,检测线性范围为2-15~2-8 HA unit·50 μL-1.此传感器特异性好,灵敏度高,在病原微生物快速检测领域具有良好的应用前景.%A novel electrochemical immunosensor for sensitive detection of avian influenza virus (AIV) H5N1 was described.A graphene oxide (GO) carrying H5N1-polychonal antibodies (PAb-H5N1) and Bovine serum albumin (BSA) were used as signal amplification materials.On the basis of the signal amplification strategy of PAb-H5N1-GO-BSA nanocomposite,the developed immunosensor showed a 256-fold increase in detection limit compared to the immunosensor without PAb-H5N1-GO-BSA nanocomposite amplification.The developed method could detect 2-15 HA unit · 50 μL-1 H5N1 with a linear calibration range from 2-15 to 2-8 HA unit · 50 μL-1.This immunosensor has a good specificity and high sensitivity,and it is promising for rapid detection of pathogenic microorganisms.

  6. 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.

  7. 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.

  8. 中国高致病性禽流感A/H5N1病毒感染患者的临床与预后%Relationship between clinical features and prognosis of highly pathogenic avian influenza A/H5N1 infection in humans in mainland China

    Institute of Scientific and Technical Information of China (English)

    李佳; 刘建南; 魏立平; 邱晨; 钟小宁; 黄美杏; 辛建保; 罗如平; 赵明顺; 李再清; 胡成平; 徐钰; 赵伟; 王虹; 张伟; 郭路生; 王秋月; 周龙女; 梁宗安; 马俊清; 刘跃建; 蒋远明; 陈余清; 谢万升; 盛吉芳; 高占成; 葛阳; 章隆辉; 徐晓玲; 吴同生; 陈愉生; 王静

    2009-01-01

    study included 28 human cases with A/H5 N1 infection in mainland China from October 2005 to May 2008.Data were collected and reviewed from hospital medical records and publishied papers.A database was built by EPIDATA 3.02 and statistical analyses were performed with SPSS 13.0.Results The median age of the 28 cases was 29 years (range 6 -62),and 15 were females.Ten patients survived,and 18 died.The typically clinical manifestations of human influenza A/H5N1 infection included fever and lower respiratory infection.The numbers of peripheral white blood cells,lymphocytes and platelets in the survival and non-survival groups were (4.01±1.86) x 109/L vs (5.1 ±2.9) x 109/L,(1.09±0.49) x 109/L vs (0.98 ±0.44) x 109/L,and (116±39) x 109/L vs (101±40) x 109/L,respectively;the differences were not statistically significant between the 2 groups (P > 0.05).There was also no statistically significant difference in the increased serum enzymes,such as aspartate aminotransferase [(173 ±246)U/L vs (272±263)U/L],lactate dehydrogenase [(1016±568) U/L vs (1512±1052) U/L],creatine kinase [(1099±1590) U/L vs (2534±4281) U/L]and MB isoenzyme of creatine kinase [(28±30) U/L us (125±197) U/L](P > 0.05) between the survival and the non-survival groups.However,there was a statistically significant difference in the number of patients with an initial LDH level more than 8 fold of the normal value between the survival and the non-survival groups (none vs 6,P 0.05).Conclusions Initial LDH level reaching more than 8 fold of the normal value suggests a poor prognosis for human H5N1 infection.Patients complicated with either ARDS or acute kidney injury had a higher risk of death.Early administration of effective anfiviral agents might improve the prognosis and decrease case fatality.

  9. Lethal dissemination of H5N1 influenza virus is associated with dysregulation of inflammation and lipoxin signaling in a mouse model of infection

    Science.gov (United States)

    Lessons learned from the Spanish influenza pandemic, the periodic outbreaks of highly pathogenic avian H5N1 influenza viruses, and the current H1N1 ("swine flu") pandemic highlight the need for a more detailed understanding of influenza virus pathogenesis and the host response to infection. To inve...

  10. 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.

  11. HUBUNGAN SIFAT ANTIGENIK VIRUS INFLUENZA A/H5N1 TAHUN 2004-2005

    OpenAIRE

    Djoko Yuwono

    2012-01-01

    Telah dilakukan analisis antigenik secara imunoserologi strain virus influenza A/H5N1 yang berasal dari manusia dan kaitannya dengan strain yang berasal dari hewan. Reaksi terhadap antibodi monoklonal menunjukkan bahwa strain A/H5N1 Indonesia terdahulu: (Indonesia /5/05/Tangerang; Indonesia 341/Jakarta; Indonesia/542/Jawa Barat; Indonesia/554/Jawa Timur; Indonesia 557/Jakarta), mempunyai sifat antigen determinan dominan yang mirip dengan protein CP176/26 dari strain virus CK/PA/1370/83 dan an...

  12. Identification of Chicken Pulmonary miRNAs Targeting PB1, PB1-F2, and N40 Genes of Highly Pathogenic Avian Influenza Virus H5N1 In Silico

    OpenAIRE

    Amod Kumar; Muhasin Asaf V.N.; Ashwin Ashok Raut; Richa Sood; Anamika Mishra

    2014-01-01

    Highly pathogenic Avian influenza (HPAI) is a notifiable viral disease caused by avian influenza type A viruses of the Orthomyxoviridae family. Type A influenza genome consists of eight segments of negative-sense RNA. RNA segment 2 encodes three proteins, PB1, PB1-F2, and N40, which are translated from the same mRNA by ribosomal leaky scanning and reinitiation. Since these proteins are critical for viral replication and pathogenesis, targeting their expression can be one of the approaches to ...

  13. 禽流感病毒H5N1亚型NS1基因在大肠杆菌中的表达%Expression of NS1 Gene of H5N1 Subtype Avian Influenza Virus in E.coli

    Institute of Scientific and Technical Information of China (English)

    孙明; 赵铁柱; 王传彬; 李纯玲; 丁银巧; 王宏伟; 陈西钊; 田克恭

    2004-01-01

    目的表达H5N1亚型禽流感病毒(AIV)NS1蛋白,用于AIV感染与注射灭活疫苗鸡的鉴别诊断和NS1蛋白功能研究.方法采用RT-PCR方法对H5N1亚型AIV NS1基因进行扩增,将PCR产物克隆于pGEM-T-easy载体,将该基因插入pGEX-4T-1中构建NS1基因原核表达载体,转化BL21大肠杆菌后,在IPTG诱导下表达NS1蛋白,Western blot鉴定表达NS1蛋白.结果成功克隆H5N1亚型AIV的NS1基因,其核苷酸序列长度为690 bp,编码230个氨基酸残基.构建NS1基因原核表达载体在大肠杆菌内表达出约51×103的NS1融合蛋白.Western blot鉴定表明:表达NS1蛋白与H7N2 AIV感染鸡血清有反应性.结论在大肠杆菌中成功表达了H5N1亚型AIV NS1基因蛋白,具有与感染H7N2亚型AIV阳性血清反应原性.

  14. H5N1流感病毒不同途径接种BALB/c小鼠临床病理学比较%Comparison of Clinical Signs and Pathologic Changes of Avian Influenza Virus(H5N1) in BALB/c Mice Inoculated by Different Routes

    Institute of Scientific and Technical Information of China (English)

    闵凡贵; 张钰; 赵维波; 王静; 刘香梅; 刘忠华; 谭文雅; 黄韧

    2007-01-01

    目的 比较BALB/c小鼠不同途径接种H5N1流感病毒产生的临床和病理学变化.方法 利用1株鹅源性H5N1流感病毒通过鼻腔、静脉和脑内等方式接种BALB/c小鼠,观察小鼠在接种后7 d内的临床症状和病理变化.结果 接种1 d后,小鼠出现明显的临床症状,接种2 d后开始出现死亡,接种5 d后,临床症状明显恢复.组织病理学检查显示,小鼠不同途径接种H5N1流感病毒后,所产生的主要病变相似,且病毒最先到达的器官损伤相对严重.从病程进展来看,接种后2 d各组织器官的病变最严重,随着时间增长,肺脏和肾脏等器官的病变有不同程度的恢复,心脏和肝脏等器官的病变在感染过程中未见明显恢复.结论 小鼠不同途径接种H5N1流感病毒后引发相似的症状,病毒最先到达的器官损伤相对严重.

  15. Pathologic Changes of Rhesus Macaques Infected with Avian influenza virus (H5N1) in a Short Period and Recovery Period Post-infection%H5N1流感病毒感染恒河猴短期和恢复期病理学观察

    Institute of Scientific and Technical Information of China (English)

    闵凡贵; 张钰; 赵维波; 王静; 刘香梅; 刘忠华; 谭文雅; 黄韧

    2006-01-01

    为观察恒河猴在感染H5N1流感病毒后短期和恢复期的病理学变化,利用1株鹅源H5N1流感病毒环甲膜穿刺接种恒河猴.感染后短期内恒河猴产生了典型的肺炎和肺外器官不同程度的损伤,3个月后,恒河猴从病理上表现恢复.病理检查结果表明,H5N1流感病毒对恒河猴的感染是一种急性的呼吸道综合征,并伴有多器官功能不全的症状,随着感染时间的延长,可通过自身免疫调节恢复正常.

  16. 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.

  17. 山西省职业暴露人群高致病性禽流感(H5N1)血清抗体水平调查%Detection of antibody against high pathogenic avian influenza (H5N1) virus in occupational exposed population in Shanxi

    Institute of Scientific and Technical Information of China (English)

    左素俊; 李国华; 张凡非; 那丹宇; 王乃昌; 高雪芬; 刘玲

    2012-01-01

    Objective To learn the current status of H5N1 infection in the population of occupationally exposed to the virus in Shanxi, and to address the relationship between the occupational exposure and virus infection. Methods A total of 207 workers were investigated. Serum antibody against H5N1 was detected using Single Radial Hemolytic Technique (SRH) method. Results The majority of occupational population exposed to H5N1 virus was young adult. Workers involved in processing (44. 93%) , feeding and cleaning (21. 74%) plus capturing (15. 94%) were more likely to get infected, although 91. 89% participants have indeed taken protective measures after dealing with sick or dead birds. Our study also showed that the overall infection rate in this population was 0. 97%, with no significant difference between the two counties with /without H1N1 epidemic (x2 =0.000, P=0. 995). Conclusions There is a possibility of latent infection among people who occupationally exposed to H5N1 virus. Also this study suggested that, strict surveillance and management are necessary in all the areas regardless their epidemic status.%目的 了解山西省职业暴露人群高致病性禽流感(H5NI)感染现状,探索高危人群的暴露情况与感染途径,为防控工作提供依据.方法 现场问卷调查职业暴露人群,用单放射免疫扩散溶血实验检测高致病性禽流感(H5N1)的血清抗体水平.结果 山西省的职业暴露人群以青壮年为主;主要暴露方式以加工(44.93%)、喂养十清扫禽舍(21.74%)和喂养十清扫禽舍十捕捉(15.94%)为主;接触病死禽时91.89%的人员采取了防护措施;研究显示山西职业暴露人群H5N1病毒的感染率为0.97%,曾经发生过高致病性禽流感疫情的县与未发生过疫情的县感染率差异无统计学意义(x2=0.000,P=0.995).结论 山西省禽类职业暴露人群可能存在H5N1隐性感染,并提示无论是否发生过禽间疫情,均需加强监测与管理.

  18. Construction of phage display VHH antibody library against avian H5N1 virus from alpaca%抗H5N1禽流感病毒VHH抗体库的构建

    Institute of Scientific and Technical Information of China (English)

    严安; 熊慧; 王颖; 孙冰玉; 夏立亮; 吴标; 包文静; 车小燕; 孙志伟; 金维荣; 赵国屏

    2011-01-01

    Objective: To construct phage display variable domain of heavy chain antibody library (VHH antibody library) from alpaca immunized with inactivated H5N1 vaccine for the future screening of VHH antibodies against avian H5N1 influenza virus. Methods: The camelid species (alpaca, Lama pacos ) was selected for immunization with inactivated H5N1 vaccine. Hemagglutinin inhibition (HI) assay of serum from immunized alpaca was performed against H5N1 avian influenza virus one week after the fourth inntmization. Peripheral lymphocytes were isolated for the amplification of VHH fragments by RT-PCR. PCR products were then purified and inserted into phagemid vector pCANTAB5E. The VHH antibody gene library was obtained by electroporating recombinant pCANTAB5E-VHH vectors into E. coli TG1 cells.The library capacity and diversity of VHH antibody gene library was determined by sequencing analysis. The HI assay was performed with the culture supernatant of primary phage display VHH antibody library. Results:After four rounds of immunization with inactivated H5N1 vaccine,HI antibody titer of the alpaca serum reached to 1: 2 560, which was higher than those fiom immunized mice. A first set of antibody gene library totalling 3 × l08 members were created after cloning VHH genes into a phagemid vector pCANTAB5E. The sequence of 14 members of the unselected library indicated that the camelid VHH antibody library we constructed possessed high diversity and good capacity. The supematant from the primary phage display library displayed effieient HI effect against avian H5N1 influenza virus. And the titration of our phage display VHH library reached 2.17 × l011. Conclusion: Taken together, phage display VHH antibody library from immunized alpaca is successfully constructed,which provides a platform for VHH antibody preparation against H5N1 virus. This will give light to future study on treatment and diagnosis of avian H5N1 influenza virus.%目的:构建抗H5N1禽流感病毒的小羊驼免

  19. H5N1亚型禽流感病毒NS1基因在昆虫细胞中的表达%The NS1 Gene of H5N1 Avian Influenza Virus(AIV) Expressed in Insect Cells

    Institute of Scientific and Technical Information of China (English)

    刘春国; 刘明; 张云; 杨涛

    2006-01-01

    H5N1亚型禽流感病毒(AIV)NS1基因插入到杆状病毒转移载体pFastBac1中,获得重组转移载体pFastBac1-NS1.将pFastBac1-NS1转化到DH10Bac感受态细胞中,筛选到重组转座子rBacmid-NS1.在脂质体转染试剂介导下将rBacmid-NS1转染对数生长期的Sf 9昆虫细胞获得重组杆状病毒rBV-NS1.rBV-NS1感染Sf 9细胞后,通过SDS-PAGE、Western blot和ELISA分析表明:获得了分子量为26kDa的特异性NS1蛋白;并且该蛋白可与H5N1 AIV攻毒鸭的血清发生特异性免疫反应,而不能与H5N1AIV灭活疫苗免疫鸭的血清发生反应.试验结果表明:NS1在Sf9昆虫细胞中获得了高效表达,具有与天然蛋白相似的免疫活性,并可以作为区分免疫及自然感染个体的鉴别诊断抗原,为建立禽流感病毒自然感染家禽与禽流感灭活疫苗免疫家禽的鉴别诊断方法奠定了基础.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  2. H5N1亚型禽流感疫苗对供港鸡免疫效果评价%Immunogenicity Evaluation of Inactived H5N1 Subtype Viccine of Avian influenza virus in Chickens Supplied to Hongkong

    Institute of Scientific and Technical Information of China (English)

    秦智锋; 吕建强; 曾少灵; 毕英佐; 田国彬; 钟安清; 林庆燕; 罗焕全; 姚绵鹏; 范万红; 陈书琨; 许保柱; 阮周曦

    2007-01-01

    针对供港活鸡饲养周期长(85日龄~105日龄),禽流感抗体滴度要求高(21/28检测样品抗体滴度需≥4 log2)的特点,在原有H5N2疫苗对供港活禽免疫效果不理想的情况下,对哈尔滨兽医研究所研制的H5N1亚型禽流感疫苗进行了免疫效果评估.结果显示,H5N1疫苗免疫效果明显高于原有的H5N2疫苗,初步推荐该禽流感灭活疫苗对供港鸡场的免疫程序为:首免7日龄~10日龄,0.3 mL/只,皮下注射;二免45日龄,0.5 mL/只,肌肉注射.

  3. Biosafety Considerations of Mammalian-Transmissible H5N1 Influenza

    OpenAIRE

    Imperiale, Michael J.; Hanna, Michael G.

    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.

  4. Analysis of the World Journal SCI Articles About H5N1 Avian Influenza from 1998 to 2007 by Bibliometrics%1998~2007年主要国家(地区)H5N1禽流感相关SCI文献统计分析

    Institute of Scientific and Technical Information of China (English)

    田德桥; 朱联辉; 郑涛

    2009-01-01

    H5NI流感病毒引起的禽流感造成了大量禽类的死亡,并且有越来越多人感染病例的发生.在本文中,我们利用PubMed数据库检索H5N1禽流感相关文献,并筛选出SCI文献进行文献数量的年度变化、国家(地区)分布、主要研究机构等方面的统计分析,以此探讨禽流感文献的分布规律和禽流感研究现状与趋势,为我国的H5NI禽流感研究提供参考.

  5. 鹅源H5N1亚型禽流感病毒感染雏鸡免疫器官的病理学观察%Observation of pathologic changes in immune organs of chickens infected with H5N1 avian influenza virus originated from goose

    Institute of Scientific and Technical Information of China (English)

    张瑞莉; 葛铭; 张卓; 郑世民

    2007-01-01

    应用组织病理学及超微病理学观察手段对H5N1亚型禽流感毒株感染雏鸡免疫器官的病理学变化进行了系统研究.结果显示,感染雏鸡胸腺、腔上囊及脾均表现不同程度的病理学损伤.表明,禽流感病毒感染可造成雏鸡免疫器官组织损伤,这是导致感染雏鸡免疫功能降低的重要机制之一.

  6. 鹅源H5N1禽流感病毒在感染雏鸡心脏的分布及所致病理变化%Viral distribution and pathologic changes in the heart of chickens infected with H5N1 avian influenza virus from goose

    Institute of Scientific and Technical Information of China (English)

    张瑞莉; 刘超男; 张卓; 刘明; 郑世民

    2010-01-01

    将120只1日龄SPF雏鸡随机分为对照组和7日龄(Ⅰ组)、21日龄(Ⅱ组)病毒感染组.Ⅰ组和Ⅱ组雏鸡分别于7和21日龄经鼻、眼、口感染鹅源H5N1亚型禽流感病毒(AIV)稀释液,3组雏鸡分别于感染后第1、3、4、5、7、14、21 d或死亡前心脏采血,并快速采取心脏,应用免疫酶组织化学染色、常规HE染色及电镜观察等方法检测了AIV在感染雏鸡心脏内的分布,并观察了心脏的形态、病理变化.结果发现,雏鸡感染AIV后1~7 d,心脏的血管内皮细胞和心肌纤维内均呈现病毒抗原阳性,并可见心肌不同程度的病理损伤.表明鹅源H5N1 AIV对雏鸡心脏具有较强的组织嗜性,可能与其导致感染雏鸡死亡密切相关.

  7. Clinical characteristics and therapeutic experience of case of severe highly pathogenic A/H5N1avian influenza with bronchopleural fistula%福建省高致病性禽流感A/H5N1病毒感染并支气管胸膜瘘患者的救治体会

    Institute of Scientific and Technical Information of China (English)

    张华平; 曾奕明; 林章树; 陈炜; 梁建生; 张宏; 黄文瑞

    2009-01-01

    目的 总结重症高致病性禽流感A/H5N1病毒感染(简称人禽流感)患者的临床特点、治疗经验以及合并支气管胸膜瘘的处理方法.方法 对2007年2月福建省建瓯市立医院成功救治的1例重症人禽流感并发右侧支气管胸膜瘘患者的临床资料和诊治过程进行回顾性分析.结果 患者女,44岁,发病前3 d有病死鸡接触史,以发热、气促为主要症状,经呼吸道分泌物检测A/H5N1病毒核酸阳性确诊.患者住院第7天发展为急性呼吸窘迫综合征,病情重、进展快,病程中出现呼吸机相关肺炎、双侧气胸、右侧支气管胸膜瘘等多种并发症.经奥司他韦抗病毒、糖皮质激素抗炎、输注康复期血浆、机械通气、抗感染等治疗,病情有所缓解,但支气管胸膜瘘持续存在并形成脓胸,导致脱机困难.经纤维支气管镜下气囊探查加选择性支气管封堵术、经纤维支气管镜右侧支气管胸膜瘘OB胶粘堵术等介入治疗,患者痊愈,发病第99天出院.结论 人禽流感并发难治性支气管胸膜瘘患者在采取抗病毒、抗感染、机械通气支持、输注康复期血浆等综合治疗的基础上结合介入治疗是可行的.%Objective To summarize the clinical charactaristics and therapeutic experience of A/ H5N1 infected patient with intractable bronchopleural fistula.Method The data of a patient with A/H5N1 infection complicated with bronchopleural fistula was collected and analyzed.Results A 44-year-old woman with pneuminian was diagnosed as A/H5N1 infection by reverse-transcription polymerase chain reaction(RT-PCR) in laboratory from the sample of secretion of respiratory tracts.She had exposed to sick or dead poultry 3 days before development of illness.She developed acute respiratory distress syndrome 7 days after onset of sickness.After comprehensive management with antiviral agents,antibiotics,convalescent serum and invasive ventilation,her clinical condition improved and turned

  8. 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.

  9. Production of antibody labeled gold nanoparticles for influenza virus H5N1 diagnosis kit development

    International Nuclear Information System (INIS)

    Preparation of colloidal gold conjugated antibodies specific for influenza A/H5N1 and its use in developing a virus A/H5N1 rapid diagnostic kit is presented. Colloidal gold nanoparticles (AuNPs) were prepared through citrate reduction. Single chain antibodies specific to H5N1 (scFv7 and scFv24) were produced using pTI2 + vector and E. coli strain HB2151. These antibodies were purified by affinity chromatography technique employing HiTrap Chelating HP columns pre-charged with Ni2 + . The method for preparation of antibody–colloidal gold conjugate was based on electrostatic force binding antibody with colloidal gold. The effect of factors such as pH and concentration of antibody has been quantitatively analyzed using spectroscopic methods after adding 1 wt% NaCl which induced AuNP aggregation. The morphological study by scanning electron microscopy (SEM) showed that the average size of the spherical AuNPs was 23 nm with uniform sizes. The spectroscopic properties of colloidal AuNPs showed the typical surface plasmon resonance band at 523 nm in UV-visible spectrum. The optimal pH of conjugated colloidal gold was found between 8.0 and 10.0. The activity of synthesized antibody labeled AuNPs for detection of H5N1 flu virus was checked by dot blot immunological method. The results confirmed the ability in detection of the A/H5N1 virus of the prepared antibody labeled gold particles and opened up the possibility of using them in manufacturing rapid detection kit for this virus. (paper)

  10. Extrapolating theoretical efficacy of inactivated influenza A/H5N1 virus vaccine from human immunogenicity studies.

    Science.gov (United States)

    Feldstein, Leora R; Matrajt, Laura; Elizabeth Halloran, M; Keitel, Wendy A; Longini, Ira M

    2016-07-19

    Influenza A virus subtype H5N1 has been a public health concern for almost 20years due to its potential ability to become transmissible among humans. Phase I and II clinical trials have assessed safety, reactogenicity and immunogenicity of inactivated influenza A/H5N1 virus vaccines. A shortage of vaccine is likely to occur during the first months of a pandemic. Hence, determining whether to give one dose to more people or two doses to fewer people to best protect the population is essential. We use hemagglutination-inhibition antibody titers as an immune correlate for avian influenza vaccines. Using an established relationship to obtain a theoretical vaccine efficacy from immunogenicity data from thirteen arms of six phase I and phase II clinical trials of inactivated influenza A/H5N1 virus vaccines, we assessed: (1) the proportion of theoretical vaccine efficacy achieved after a single dose (defined as primary response level), and (2) whether theoretical efficacy increases after a second dose, with and without adjuvant. Participants receiving vaccine with AS03 adjuvant had higher primary response levels (range: 0.48-0.57) compared to participants receiving vaccine with MF59 adjuvant (range: 0.32-0.47), with no observed trends in primary response levels by antigen dosage. After the first and second doses, vaccine with AS03 at dosage levels 3.75, 7.5 and 15mcg had the highest estimated theoretical vaccine efficacy: Dose (1) 45% (95% CI: 36-57%), 53% (95% CI: 42-63%) and 55% (95% CI: 44-64%), respectively and Dose (2) 93% (95% CI: 89-96%), 97% (95% CI: 95-98%) and 97% (95% CI: 96-100%), respectively. On average, the estimated theoretical vaccine efficacy of lower dose adjuvanted vaccines (AS03 and MF59) was 17% higher than that of higher dose unadjuvanted vaccines, suggesting that including an adjuvant is dose-sparing. These data indicate adjuvanted inactivated influenza A/H5N1 virus vaccine produces high theoretical efficacy after two doses to protect individuals

  11. 几种圈养珍稀雉鸡H5N1禽流感疫苗免疫后抗体水平研究%Immune Antibody Monitoring of H5N1 Type Avian Influenza For Rare Species of Pheasant

    Institute of Scientific and Technical Information of China (English)

    李莹; 吴秀山; 张成林; 刘燕; 闫鹤; 杨明海; 原蕾

    2011-01-01

    家禽对禽流感疫苗免疫效果的研究多有报道,但现有的禽流感疫苗对野生禽类的有效性尚所知甚少.本文以白冠长尾雉、蓝鹇、红腹锦鸡、白腹锦鸡4组野生雉鸡类为研究对象,以家鸡为对照,进行禽流感H5N1亚型疫苗免疫.利用血凝(HA)及血凝抑制(HI)实验,分别在首免日、免后10 d、20 d、40 d、60 d、90 d及120 d监测禽类免疫后抗体水平变化.结果显示,4组野生雉鸡类均在疫苗接种后产生禽流感抗体,且达到具保护力的抗体水平.通过免疫后抗体水平的跟踪研究,证明商品化禽流感疫苗对野生雉鸡类动物有效.

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

    Directory of Open Access Journals (Sweden)

    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

  13. Immune injury induced by H5N1 subtype influenza virus%H5N1亚型禽流感病毒诱导的机体免疫损伤分析

    Institute of Scientific and Technical Information of China (English)

    吕星; 王晓辉; 吴春利; 王昕; 房师松; 程小雯; 张仁利; 彭博

    2013-01-01

    In order to understand the pathogenic mechanism of avian influenza virus and provide the scientific basis for effective therapeutic strategies,peripheral blood lymphocyte counts and cytokine of a man infected with H5N1 virus in Shenzhen were detected by flow cytometric analysis and ELISA assay.Compared with those of healthy control,the numbers of pe ripheral B,NK,CD4+ T,and CD8+ T cell in patient infected with H5N1 were significantly decreased,and the inverted ratios of CD4+ to CD8+ cells was detected.Cytokine analysis showed the high levels of serum IL-6,IL-10,TNF,IFN-γ,IL-12,IP-10,and MCP-1.These findings indicated that H5N1 virus could be the cause of serious damage to body's immune system,including cellular immunity and humoral immunity.Cytokines are essential for efficient elimination of virus.However,hyper-activation of inflammatory cytokines may initiate or exacerbate pathological damage in this viral infection.%目的 进一步了解H5N1禽流感病毒的致病机制,同时对H5N1禽流感病人的临床救治方案提供科学依据.方法 采集2011年深圳市1例H5N1禽流感病例病程中多份血液样本,应用流式细胞术和酶联免疫法,检测该病人外周血中各亚群淋巴细胞及细胞因子水平.结果 H5N1禽流感患者外周血中各亚群淋巴细胞均出现绝对数量减少,CD4+/CD8+出现倒置.同时发现血清中高水平的IL-6、IL-10、TNF、IFN-γ、IL-12、IP-10和MCP-1.结论 H5N1禽流感病毒会对机体的免疫系统造成严重伤害,同时会刺激机体过度表达高水平的细胞因子,从而导致典型的免疫应答介导的病理损伤.

  14. 一株鸭源H5N1亚型禽流感病毒人工感染鸡的病理学研究%Pathology of Chickens Experimentally Infected with a Highly Pathogenic Avian Influenza Virus,A/duck/Guangdong/220/2004(H5N1)

    Institute of Scientific and Technical Information of China (English)

    李玉谷; 张媛; 崔聪颖

    2010-01-01

    鸡经肌肉或眼-鼻-口腔-泄殖腔接种禽流感病毒A/duck/Guangdong/220/2004(H5N1)后,发病率和死亡率均为100%,死亡发生在接种后6 d内.全身多数器官出现充血、淤血、出血、血栓形成、组织水肿和炎症,主要有血管炎、病毒性心肌炎、病毒性肝炎、气管炎、出血性卡他性肺炎、肾小管性肾炎、肾小球性肾炎、坏死性胰腺炎、坏死性胸腺炎、坏死性法氏囊炎、脾炎、非化脓性脑炎、溃疡性肠炎等.电镜下可见心、肝、肾、胰、脾、胸腺等器官的实质细胞发生坏死和凋亡两种变化.鸡接种该病毒后,通常血清中的天门冬氨酸氨基转移酶(谷草转氨酶)、γ-谷氨酰基转移酶、碱性磷酸酶先升高,后下降;而肌酸激酶则升高,α-淀粉酶则下降.结果表明,许多器官的严重损伤是造成鸡死亡的原因,而该病毒的致病机制可能与细胞坏死和细胞凋亡有关.

  15. NMR identification of anti-influenza lead compound targeting at PAc subunit of H5N1 polymerase

    Institute of Scientific and Technical Information of China (English)

    Lin Li; Sheng Hai Chang; Jun Feng Xiang; Qian Li; Huan Huan Liang; Ya Lin Tang; Ying Fang Liu

    2012-01-01

    PAC subunit from avian influenza (H5N 1) viral RNA polymerase was used in this work as a target in the screening for antiinfluenza agents from licorice-derived compounds.As a result,18β-glycyrrhetinic acid was suggested to be PAC ligand by flexible docking,and was then confirmed by relaxation-edited NMR.The result of ApG primer extension assay indicated that this PAC ligand can inhibit the polymerase activity,and thus may potentially be valuable as anti-influenza lead compound.This work validated the possibility of screening polymerase inhibitors by using PAc as a target,and provided a starting point for the further discovery of new anti-influenza drugs.

  16. H5N1亚型禽流感病毒NS1基因在大肠杆菌和昆虫细胞中的表达%Expression of the NS1 gene of H5N1 avian influenza virus in E.coli and insect cells

    Institute of Scientific and Technical Information of China (English)

    刘波; 薛仁宇; 曹广力; 贡成良

    2007-01-01

    目的 构建大肠杆菌表达载体pET-NS1和昆虫杆状病毒转移载体pFast-NS1,将H5N1亚型禽流感病毒NS1基因分别在大肠杆菌和昆虫细胞中进行表达,表达产物用Western blot进行检测分析.方法 酶切含有NS1基因的质粒pUC-NS1,分别克隆进大肠杆菌表达载体pET-28a(+)和杆状病毒转移载体pFastBacHT A中,分别获得表达载体pET-NS1和pFast-NS1.将pET-NS1转化大肠杆菌BL21,以异丙基硫代半乳糖苷(IPTG)进行诱导表达;将pFast-NS1转化DH10Bac感受态细胞,提取重组Bac-NS1 DNA,以M13为通用引物作PCR鉴定,阳性Bac-NS1用脂质体转染sf9细胞,72 h后收集感染细胞.大肠杆菌表达产物和细胞表达产物分别裂解后作SDS-PAGE和Western blot分析.结果 成功构建了大肠杆菌表达载体pET-NS1和昆虫杆状病毒转移载体pFast-NS1,大肠杆菌和昆虫细胞中表达的融合蛋白Western blot都能检测到特异性条带.结论 NS1基因在大肠杆菌和昆虫细胞中得到成功表达,为获得大量NS1蛋白进行功能研究及抗体制备奠定了基础.

  17. Pathologic changes caused by highly pathogenic H5N1 avian influenza virus: postmortem study of a case%人感染高致病性禽流感病毒H5N1尸体解剖病理分析

    Institute of Scientific and Technical Information of China (English)

    白燕琼; 徐钢; 龚自力; 李世辉; 徐玉川; 李科; 胥维勇

    2006-01-01

    目的 探讨人感染禽流感死亡病例尸体解剖组织的病理学特征.方法 尸体解剖1例人感染H5N1高致病性禽流感病毒死亡病例,对其心、肺、肝、脾、肾和大脑等组织进行光镜观察,对肺组织进行了组织化学和免疫组织化学表型以及电镜观察.结果 人感染禽流感的主要病变为双肺弥漫性肺泡损伤,透明膜形成,以及多灶性出血.肺泡腔内充满淡红粉染物(即水肿液)和不等量的各种炎细胞,炎细胞以淋巴细胞、单核细胞、浆细胞和少许中性粒细胞以及吞噬细胞为主.肺泡壁血管广泛性扩张淤血,部分肺泡壁透明膜形成.免疫组织化学染色显示:炎细胞主要以T淋巴细胞和单核细胞为主.结论 人感染禽流感病理形态学改变以肺部最明显,主要为双肺弥漫性肺泡损伤,急性弥漫性渗出性病变,渗出的细胞以T淋巴细胞和单核细胞为主.肺部广泛性实变、肺水肿、肺出血导致呼吸窘迫是本病的主要死因.

  18. 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.

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

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    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.

  20. Tapak Perlekatan Reseptor Virus Flu Burung yang Diisolasi dari Berbagai Unggas Sejak tahun 2003 sampai 2008 (RECEPTOR BINDING SITE OF AVIAN INFLUENZA VIRUS H5N1 ISOLATED FROM VARIOUS POULTRIES SINCE 2003 TO 2008

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    Michael Haryadi Wibowo

    2014-08-01

    Full Text Available Avian Influenza (AI is an infectious disease in poultry, caused by type A of avian influenza virus(AIV, in the family of Orthomyxoviridae. Almost all birds’ species are sensitive to the AI. Beside theability to infect various species of poultry. AIV type A has a wide range of host including all bird species,mammals, dan human. Today some scientists reported that the cases of AI in mammals, including humansare increasing. This condition suggests that the AI virus circulated in the field may have some mutationsin the amino acid determinants responsible receptor binding site (RBS. A research was therefore designedto investigate the molecular level of HA gen fragment responsible for receptor binding site of AIV isolatedfrom various poultry since 2003 to 2008. Molecular characterization was based on the amplification ofreceptor binding site of HA gene by reverse transcriptase polymerase chain reaction (RT-PCR. All RTPCRof HA gene positive products were sequenced to determine the nucleotide composition at the targetedfragment. Sequences yielded were analyzed by program Mega 4.0 versions, including multiple alignment,deductive amino acid prediction, and establishment of phylogenetic tree. The results show that all AIVisolates could be determined of some conserved amino acids residues responsible for RBS which indicatethe binding preference of avian like receptor, sialic acid ? 2, 3 galactose except isolate A/Layer/Jabar/MHW-RBS-02/2008 which could be found a deletion of amino acid at position of 129 dan mutation of 151isoleucine into threonine. Phylogenetic study showed that clustering of AIV did not base on species of birdor geographic origin of AI viruses which were studied.

  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. 我国部分禽流感病毒H5N1之HA序列变异演化分析%Analysis of HA Gene's Variation and Evolution in Some Avian Influenza Viruses from China

    Institute of Scientific and Technical Information of China (English)

    张继荣; 雷富民

    2008-01-01

    从GenBank上获得我国人(Homo sapiens)、家禽和野鸟42株H5N1亚型禽流感病毒的HA基因核酸序列,利用DNAStar分析HA蛋白关键位点氨基酸残基的变化,比较HA基因核苷酸序列同源性,构建遗传进化树.探讨我国部分人、家禽和野鸟H5N1病毒基因的遗传进化关系.序列分析结果表明:禽流感病毒H5N1亚型的HA基因持续地发生着变异,但并非以均一速度进行,时间间隔愈长,核苷酸同源性愈低;我国同一地区或临近地区,当年或前后两年发生的人及家禽感染的禽流感病毒高度同源.推测我国部分人发生的禽流感可能是通过家禽感染的;候鸟的迁徙在传播病毒过程中所起的作用有待深入探讨.

  3. The primer design of domain-specific C-terminus of the avian H5N1 NS gene from Indonesia

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    Kindi Adam

    2015-01-01

    Full Text Available AbstrakLatar belakang: Virus avian influenza (AI H5N1 telah menyebabkan kematian hampir 600 orang di dunia sejak tahun 2003. Virus AI H5N1 masih beredar pada unggas liar dan domestik. Salah satu sifat patogenitas virus AI  diketahui dari kemampuan protein nonstructural (NS1 dan NS2 dalam menginduksi badai sitokin. Mutasi yang terjadi pada protein NS1 dan NS2 dapat memperberat infeksi yang terjadi. Metode: Sekuens genetik gen NS yang mengkode domain C-terminus dari virus AI H5N1 didapat dengan metode sekuensing menggunakan primer khusus untuk mengamplifikasi gen NS. Desain primer dilakukan dengan menggunakan beberapa software bioinformatika yang tersedia kemudian primer diuji kembali untuk mengetahui keberhasilan dalam mengamplifikasi sekuen target. Pengujian RT-PCR dilakukan pada empat isolat virus AI H5N1, dilanjutkan dengan sekuensing untuk mengetahui urutan basa nukleotida yang dihasilkan dari primer yang dibuat dalam penelitian ini. Hasil: Primer yang didesain dapat mengamplifikasi empat isolat H5N1 ayam yang diuji yaitu dua isolat dari Bali (A/Ck/Bali-KH/2009 dan A/Ck/Bali-T/2009,serta dua isolat dari Jawa Timur (A/Ck/Jawa Timur-S/2009 dan A/Ck/Jawa Timur-D/2009.Kesimpulan: Primer yang didesain dapat digunakan dalam amplifikasi PCR dan sekuensing gen NS yang mengekspresikan bagian C terminus dari protein NS1 dan bagian ujung NS2. (Health Science Indones2014;2:83-8Kata kunci: avian influenza, H5N1, gen NS, C-terminusAbstractBackground: The avian influenza (AI H5N1 viruses have caused nearly 600 fatal cases in the world since 2003. The H5N1 AI virus is still circulating in wild birds and domestic. One of the known of AI virus pathogenicity is the ability of the nonstructural protein (NS1 and NS2 to induce cytokine storm. Mutations of the NS1 and NS2 proteins may aggravate infections.Methods: Genetic sequences of NS gene that encodes the C - terminus domain of AI H5N1 virus were obtained by sequencing method using specific primer to amplify

  4. H5N1禽流感病毒NS1蛋白与干扰素诱导蛋白10表达的相关性研究%Influence of avian influenza virus NS1 protein on the expression of IP-10 in BEAS-2B cells

    Institute of Scientific and Technical Information of China (English)

    贾晓俊; 周剑芳; 王晶钰; 董婕; 薄洪; 李梓; 李魁彪; 蓝雨; 舒跃龙

    2008-01-01

    目的 研究高致病性禽流感(HPAI)H5N1病毒NS1蛋白对干扰素诱导蛋白10(IP-10)的影响.方法 分别将禽流感病毒A/Anhui/1/2005(H5N1)的NS1基因、插入80-84位缺失氨基酸的NS1突变基因及流感病毒A/Puerto Rico/8/1934(H1N1)的NS1基因克隆至真核表达载体pEGFP-N1,转染人支气管上皮细胞BEAS-2B,流式细胞仪检测转染细胞内IP-10的表达情况.结果 与pEGFP-N1对照组相比,三种NS1蛋白均能下调BEAS-2B细胞IP-10的表达(P0.01).结论 A/Anhui/1/2005(H5N1)禽流感病毒单一NS1蛋白能够抑制BEAS-2B细胞IP-10表达,但这并不能完全阐明其与病毒致病性之间的关系.%Objective To investigate the influence of avian influenza virus (AIV) NS1 protein on the expression of interferon-inducible protein 10 (IP-10). Methods NS1 gene from virus A/Anhui/1/2005 (H5N1),NS1 gene inserted with 80-84 amino acids from virus A/Anhui/1/2005(H5N1)and NS1 gene from virus A/Puerto Rico/8/1934 (H1N1) were cloned into the eukaryotic expression vector pEGFP-N1, and transected into BEAS-2Bcells, IP-10 expression level in transected cells was detected by flow cytometry. Results Compared with the control group pEGFP-N1, Expression of these three different NS1 genes can down-regulate the expression of IP-10in BEAS-2B cells, but there is no significant difference as to the lower level among them. Conclusion NS1protein of A/Anhui/1/2005(H5N1) can down-regulate the expression level of IP-10, but this may not clarify its relationship with the virulence of AIV.

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

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    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.

  6. A high-affinity CDR-grafted antibody against influenza A H5N1 viruses recognizes a conserved epitope of H5 hemagglutinin.

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    Feifei Xiong

    Full Text Available Highly pathogenic avian influenza (HPAI H5N1 virus infection is still a potential threat to public health worldwide. While vaccines and antiviral drugs are currently under development, neutralizing antibodies could offer an alternative strategy to prevent and treat H5N1 virus infection. In the present study, we had developed a humanized antibody against H5N1 viruses from mouse-derived hybridoma in order to minimize its immunogenicity for potential clinical application. The humanized antibody hH5M9 was generated by transferring the mouse complementarity determining region (CDR residues together with four key framework region (FR residues onto the FR of the human antibody. This humanized antibody exhibited high affinity and specificity comparable to the parental mouse or chimeric counterpart with broad and strong neutralization activity against all H5N1 clades and subclades except for Egypt clades investigated. Furthermore, through epitope mapping we identified a linear epitope on the top region of hemagglutinin (HA that was H5N1 specific and conserved. Our results for the first time reported a humanized antibody against H5N1 viruses by CDR grafting method. With the expected lower immunogenicity, this humanized antibody was expected to be more efficacious than murine or human-mouse chimeric antibodies for future application in humans.

  7. 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.

  8. Preliminary screening of different permeation enhancers in transcutaneous immunization with inactivated human highly pathogenic avian influenza vaccine%高致病性人禽流感H5N1透皮疫苗促渗剂的初步筛选

    Institute of Scientific and Technical Information of China (English)

    孙艳丽; 张洪刚; 孙艳花; 鹿文葆; 王希良

    2010-01-01

    目的 初步筛选用于高致病性人禽流感H5N1透皮疫苗的较有效的促渗剂.方法 选用乙醇、丙二醇、二甲基亚砜、维甲酸、油酸作为促渗剂,将其应用于BALB/c小鼠,再用灭活的高致病性人禽流感H5N1透皮疫苗免疫小鼠,通过评价透皮免疫应答的效果对促渗剂进行初步筛选.结果 二甲基亚砜、维甲酸组和油酸组血清IgG抗体效价明显高于其他促渗剂组(P<0.05).结论 在高致病性人禽流感H5N1透皮疫苗的小鼠模型中,二甲基亚砜、维甲酸和油酸是较好的促渗剂.%Objective To screen the potent permeation enhancers used in transcutaneous immunization with inactivated highly pathogenic avian influenza vaccine. Methods Five different permeation enhancers, ethanol, propylene glycol, dimethyl sulfoxide, ratinoic acid, oleic acid, were used to treat the skin of BALB/c mice before transcutaneous immunization. Sera were collected before the flist 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 ( HAI), IFN-γand IL-4 produced by splenic lymphocytes were also detected. Except that, clinical symptom of the skin in different time points and skin pathological changes were observed. Results The serum IgG titers, HAI titers and the influenza virus-specific lgA and IgG in lung and nasal lavages in the groups of HA +CT + DMSO, HA + CT + RA and HA + CT + OA were significantly higher than those of HA and HA + CT groups( P <0.05). Moreover, the numbers of splenic lymphocytes producing IFN-γ and IL-4 were increased in the above three groups than those in control groups. In addition, no evident clinical symptoms were observed, but stratum corneum of the skin in different groups showed different changes. Conclusion DMSO,RA and OA are potent permeation enhancers in mouse model inoculated with

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

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    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

  10. 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.

  11. Immunomorphologic Manifestations in Mice Liver Infected with Influenza A/H5N1, A/Goose/Krasnoozerskoye/627/05 Strain

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    Oxana V. Potapova

    2013-01-01

    Full Text Available Highly pathogenic avian influenza H5N1 (HPAI H5N1 viruses can infect mammals, including humans, causing severe systemic disease with the inhibition of the immune system and a high mortality rate. In conditions of lymphoid tissue depletion, the liver plays an important role in host defence against viruses. The changes in mice liver infected with HPAI H5N1 virus A/goose/Krasnoozerskoye/627/05 have been studied. It has been shown that the virus persistence in the liver leads to the expression of proinflammatory cytokines (TNF-α, IL-6 and intracellular proteases (lysozyme, cathepsin D, and myeloperoxidase by Kupffer cells. Defective antiviral response exacerbates destructive processes in the liver accelerating the development of liver failure.

  12. Emerging infectious diseases: Focus on infection control issues for novel coronaviruses (Severe Acute Respiratory Syndrome-CoV and Middle East Respiratory Syndrome-CoV), hemorrhagic fever viruses (Lassa and Ebola), and highly pathogenic avian influenza viruses, A(H5N1) and A(H7N9).

    Science.gov (United States)

    Weber, David J; Rutala, William A; Fischer, William A; Kanamori, Hajime; Sickbert-Bennett, Emily E

    2016-05-01

    Over the past several decades, we have witnessed the emergence of many new infectious agents, some of which are major public threats. New and emerging infectious diseases which are both transmissible from patient-to-patient and virulent with a high mortality include novel coronaviruses (SARS-CoV, MERS-CV), hemorrhagic fever viruses (Lassa, Ebola), and highly pathogenic avian influenza A viruses, A(H5N1) and A(H7N9). All healthcare facilities need to have policies and plans in place for early identification of patients with a highly communicable diseases which are highly virulent, ability to immediately isolate such patients, and provide proper management (e.g., training and availability of personal protective equipment) to prevent transmission to healthcare personnel, other patients and visitors to the healthcare facility. PMID:27131142

  13. Emerging infectious diseases: Focus on infection control issues for novel coronaviruses (Severe Acute Respiratory Syndrome-CoV and Middle East Respiratory Syndrome-CoV), hemorrhagic fever viruses (Lassa and Ebola), and highly pathogenic avian influenza viruses, A(H5N1) and A(H7N9).

    Science.gov (United States)

    Weber, David J; Rutala, William A; Fischer, William A; Kanamori, Hajime; Sickbert-Bennett, Emily E

    2016-05-01

    Over the past several decades, we have witnessed the emergence of many new infectious agents, some of which are major public threats. New and emerging infectious diseases which are both transmissible from patient-to-patient and virulent with a high mortality include novel coronaviruses (SARS-CoV, MERS-CV), hemorrhagic fever viruses (Lassa, Ebola), and highly pathogenic avian influenza A viruses, A(H5N1) and A(H7N9). All healthcare facilities need to have policies and plans in place for early identification of patients with a highly communicable diseases which are highly virulent, ability to immediately isolate such patients, and provide proper management (e.g., training and availability of personal protective equipment) to prevent transmission to healthcare personnel, other patients and visitors to the healthcare facility.

  14. PB1-F2 proteins from H5N1 and 20 century pandemic influenza viruses cause immunopathology.

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    Julie L McAuley

    Full Text Available With the recent emergence of a novel pandemic strain, there is presently intense interest in understanding the molecular signatures of virulence of influenza viruses. PB1-F2 proteins from epidemiologically important influenza A virus strains were studied to determine their function and contribution to virulence. Using 27-mer peptides derived from the C-terminal sequence of PB1-F2 and chimeric viruses engineered on a common background, we demonstrated that induction of cell death through PB1-F2 is dependent upon BAK/BAX mediated cytochrome c release from mitochondria. This function was specific for the PB1-F2 protein of A/Puerto Rico/8/34 and was not seen using PB1-F2 peptides derived from past pandemic strains. However, PB1-F2 proteins from the three pandemic strains of the 20(th century and a highly pathogenic strain of the H5N1 subtype were shown to enhance the lung inflammatory response resulting in increased pathology. Recently circulating seasonal influenza A strains were not capable of this pro-inflammatory function, having lost the PB1-F2 protein's immunostimulatory activity through truncation or mutation during adaptation in humans. These data suggest that the PB1-F2 protein contributes to the virulence of pandemic strains when the PB1 gene segment is recently derived from the avian reservoir.

  15. 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.

  16. Oseltamivir is adequately absorbed following nasogastric administration to adult patients with severe H5N1 influenza.

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    Walter R J Taylor

    Full Text Available In the absence of a parenteral drug, oral oseltamivir is currently recommended by the WHO for treating H5N1 influenza. Whether oseltamivir absorption is adequate in severe influenza is unknown. We measured the steady state, plasma concentrations of nasogastrically administered oseltamivir 150 mg bid and its active metabolite, oseltamivir carboxylate (OC, in three, mechanically ventilated patients with severe H5N1 (male, 30 yrs; pregnant female, 22 yrs and severe H3N2 (female, 76 yrs. Treatments were started 6, 7 and 8 days after illness onset, respectively. Both females were sampled while on continuous venovenous haemofiltration. Admission and follow up specimens (trachea, nose, throat, rectum, blood were tested for RNA viral load by reverse transcriptase PCR. In vitro virus susceptibility to OC was measured by a neuraminidase inhibition assay. Admission creatinine clearances were 66 (male, H5N1, 82 (female, H5N1 and 6 (H3N2 ml/min. Corresponding AUC(0-12 values (5932, 10,951 and 34,670 ng.h/ml and trough OC concentrations (376, 575 and 2730 ng/ml were higher than previously reported in healthy volunteers; the latter exceeded 545 to 3956 fold the H5N1 IC(50 (0.69 ng/ml isolated from the H5N1 infected female. Two patients with follow-up respiratory specimens cleared their viruses after 5 (H5N1 male and 5 (H3N2 female days of oseltamivir. Both female patients died of respiratory failure; the male survived. 150 mg bid of oseltamivir was well absorbed and converted extensively to OC. Virus was cleared in two patients but two patients died, suggesting viral efficacy but poor clinical efficacy.

  17. Characterization of conserved properties of hemagglutinin of H5N1 and human influenza viruses: possible consequences for therapy and infection control

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    Glisic Sanja

    2009-04-01

    Full Text Available Abstract Background Epidemics caused by highly pathogenic avian influenza virus (HPAIV are a continuing threat to human health and to the world's economy. The development of approaches, which help to understand the significance of structural changes resulting from the alarming mutational propensity for human-to-human transmission of HPAIV, is of particularly interest. Here we compare informational and structural properties of the hemagglutinin (HA of H5N1 virus and human influenza virus subtypes, which are important for the receptor/virus interaction. Results Presented results revealed that HA proteins encode highly conserved information that differ between influenza virus subtypes H5N1, H1N1, H3N2, H7N7 and defined an HA domain which may modulate interaction with receptor. We also found that about one third of H5N1 viruses which are isolated during the 2006/07 influenza outbreak in Egypt possibly evolve towards receptor usage similar to that of seasonal H1N1. Conclusion The presented results may help to better understand the interaction of influenza virus with its receptor(s and to identify new therapeutic targets for drug development.

  18. Increased inducible nitric oxide synthase expression in organs is associated with a higher severity of H5N1 influenza virus infection.

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    Simon Burggraaf

    Full Text Available BACKGROUND: The mechanisms of disease severity caused by H5N1 influenza virus infection remain somewhat unclear. Studies have indicated that a high viral load and an associated hyper inflammatory immune response are influential during the onset of infection. This dysregulated inflammatory response with increased levels of free radicals, such as nitric oxide (NO, appears likely to contribute to disease severity. However, enzymes of the nitric oxide synthase (NOS family such as the inducible form of NOS (iNOS generate NO, which serves as a potent anti-viral molecule to combat infection in combination with acute phase proteins and cytokines. Nevertheless, excessive production of iNOS and subsequent high levels of NO during H5N1 infection may have negative effects, acting with other damaging oxidants to promote excessive inflammation or induce apoptosis. METHODOLOGY/PRINCIPAL FINDINGS: There are dramatic differences in the severity of disease between chickens and ducks following H5N1 influenza infection. Chickens show a high level of mortality and associated pathology, whilst ducks show relatively minor symptoms. It is not clear how this varying pathogenicty comes about, although it has been suggested that an overactive inflammatory immune response to infection in the chicken, compared to the duck response, may be to blame for the disparity in observed pathology. In this study, we identify and investigate iNOS gene expression in ducks and chickens during H5N1 influenza infection. Infected chickens show a marked increase in iNOS expression in a wide range of organs. Contrastingly, infected duck tissues have lower levels of tissue related iNOS expression. CONCLUSIONS/SIGNIFICANCE: The differences in iNOS expression levels observed between chickens and ducks during H5N1 avian influenza infection may be important in the inflammatory response that contributes to the pathology. Understanding the regulation of iNOS expression and its role during H5N1

  19. [DNA vaccination via in vivo electroporation can elicit specific immune response against highly pathogenic H5N1 influenza viral structural antigens in mice].

    Science.gov (United States)

    Wang, Wen; Chen, Hong; Tan, Wen-jie; Deng, Yao; Wang, Min; Liu, Yuan; Yin, Xiao; Zhang, Ke; Guan, Jie; Zhou, Jian-fang; Shu, Yue-long; Ruan, Li

    2010-05-01

    This study aims to develop inexpensive and effective experimental vaccines against highly pathogenic H5N1 Avian Influenza (HPAI) virus and to optimize their immunization programs. To this end, we first synthesized the codon-optimized hemagglutinin gene (HAop) and neuraminidase gene (NAop), both of which were derived from a H5N1 virus (Anhui strain), and constructed successfully the DNA vaccines containing a single cistronic construct (HAwt, HAop, or NAop) or a bicistronic construct (HAop/M2 or NAop/M1) of H5N1 influenza virus origin. Their expression was confirmed by indirect immunofluorescent assay (IFA) and Western blotting. Then twice vaccination of mice with the DNA vaccines by injection intramuscularly or in vivo electroporation (EP) via two different routes was evaluated and analyzed by hemagglutination inhibition (HI) assay, NA-specific antibody detection, micro-neutralizing antibody test and IFN-gamma ELISpot assay. Our results showed that the DNA vaccines with coden-optimized HAop and NAop constructs could quickly elicit a strong immune response by in vivo EP, especially the cellular immune response against HA and NA; the in vivo EP via intradermal route induced stronger humoral immune responses than those via intramuscular route. Our findings will pave a way for further development of novel DNA-based H5N1 vaccine and for the optimization of the immunization programs of DNA vaccine. PMID:20572336

  20. Viral replication rate regulates clinical outcome and CD8 T cell responses during highly pathogenic H5N1 influenza virus infection in mice.

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    Yasuko Hatta

    Full Text Available Since the first recorded infection of humans with H5N1 viruses of avian origin in 1997, sporadic human infections continue to occur with a staggering mortality rate of >60%. Although sustained human-to-human transmission has not occurred yet, there is a growing concern that these H5N1 viruses might acquire this trait and raise the specter of a pandemic. Despite progress in deciphering viral determinants of pathogenicity, we still lack crucial information on virus/immune system interactions pertaining to severe disease and high mortality associated with human H5N1 influenza virus infections. Using two human isolates of H5N1 viruses that differ in their pathogenicity in mice, we have defined mechanistic links among the rate of viral replication, mortality, CD8 T cell responses, and immunopathology. The extreme pathogenicity of H5N1 viruses was directly linked to the ability of the virus to replicate rapidly, and swiftly attain high steady-state titers in the lungs within 48 hours after infection. The remarkably high replication rate of the highly pathogenic H5N1 virus did not prevent the induction of IFN-β or activation of CD8 T cells, but the CD8 T cell response was ineffective in controlling viral replication in the lungs and CD8 T cell deficiency did not affect viral titers or mortality. Additionally, BIM deficiency ameliorated lung pathology and inhibited T cell apoptosis without affecting survival of mice. Therefore, rapidly replicating, highly lethal H5N1 viruses could simply outpace and overwhelm the adaptive immune responses, and kill the host by direct cytopathic effects. However, therapeutic suppression of early viral replication and the associated enhancement of CD8 T cell responses improved the survival of mice following a lethal H5N1 infection. These findings suggest that suppression of early H5N1 virus replication is key to the programming of an effective host response, which has implications in treatment of this infection in humans.

  1. Viral replication rate regulates clinical outcome and CD8 T cell responses during highly pathogenic H5N1 influenza virus infection in mice.

    Science.gov (United States)

    Hatta, Yasuko; Hershberger, Karen; Shinya, Kyoko; Proll, Sean C; Dubielzig, Richard R; Hatta, Masato; Katze, Michael G; Kawaoka, Yoshihiro; Suresh, M

    2010-10-07

    Since the first recorded infection of humans with H5N1 viruses of avian origin in 1997, sporadic human infections continue to occur with a staggering mortality rate of >60%. Although sustained human-to-human transmission has not occurred yet, there is a growing concern that these H5N1 viruses might acquire this trait and raise the specter of a pandemic. Despite progress in deciphering viral determinants of pathogenicity, we still lack crucial information on virus/immune system interactions pertaining to severe disease and high mortality associated with human H5N1 influenza virus infections. Using two human isolates of H5N1 viruses that differ in their pathogenicity in mice, we have defined mechanistic links among the rate of viral replication, mortality, CD8 T cell responses, and immunopathology. The extreme pathogenicity of H5N1 viruses was directly linked to the ability of the virus to replicate rapidly, and swiftly attain high steady-state titers in the lungs within 48 hours after infection. The remarkably high replication rate of the highly pathogenic H5N1 virus did not prevent the induction of IFN-β or activation of CD8 T cells, but the CD8 T cell response was ineffective in controlling viral replication in the lungs and CD8 T cell deficiency did not affect viral titers or mortality. Additionally, BIM deficiency ameliorated lung pathology and inhibited T cell apoptosis without affecting survival of mice. Therefore, rapidly replicating, highly lethal H5N1 viruses could simply outpace and overwhelm the adaptive immune responses, and kill the host by direct cytopathic effects. However, therapeutic suppression of early viral replication and the associated enhancement of CD8 T cell responses improved the survival of mice following a lethal H5N1 infection. These findings suggest that suppression of early H5N1 virus replication is key to the programming of an effective host response, which has implications in treatment of this infection in humans.

  2. Electrochemical immunosensor for detection of antibodies against influenza A virus H5N1 in hen serum.

    Science.gov (United States)

    Jarocka, Urszula; Sawicka, Róża; Góra-Sochacka, Anna; Sirko, Agnieszka; Zagórski-Ostoja, Włodzimierz; Radecki, Jerzy; Radecka, Hanna

    2014-05-15

    This paper describes the development of an immunosensor for detection of anti-hemagglutinin antibodies. Its preparation consists of successive modification steps of glassy carbon electrodes: (i) creation of COOH groups, (ii) covalent immobilization of protein A with EDC/NHS coupling reaction, (iii) covering with anti-His IgG monoclonal antibody, (iv) immobilization of the recombinant His-tagged hemagglutinin (His6-H5 HA), (v) filling free space with BSA. The interactions between two variants of recombinant HA (short and long) from highly pathogenic avian influenza virus H5N1 and the anti-H5 HA monoclonal antibody (Mab 6-9-1) have been explored with electrochemical impedance spectroscopy (EIS). The impedimetric immunosensor displayed a very good detection limit (LOD) of 2.1 pg/mL, the quantification limit (LOQ) of 6.3 pg/mL and a dynamic range from 4 pg/mL to 20 pg/mL. In addition, this analytical device was applied for detection of antibodies against His6-H5 HA in serum of vaccinated hen using serial 10-fold dilutions of serum. The immunosensor proposed was able to detect antibody in hen serum diluted up to 7 × 10(7)-fold. The sensitivity of immunosensor was about four orders of magnitude much better than ELISA. PMID:24412426

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

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    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.

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

    OpenAIRE

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

    2016-01-01

    Acute lung injury, including impaired alveolar fluid clearance, is a life-threatening complication of severe respiratory virus infection, and effective treatment is lacking. Understanding the mechanism of this complication may suggest novel therapies. Here, we found that, in vitro, influenza A/H5N1 infection impaired alveolar fluid clearance more than did seasonal virus, mimicking its greater severity in patients. We demonstrated that this impairment is mediated by the release of soluble fact...

  5. CD8+ Treg cells suppress CD8+ T cell-responses by IL-10-dependent mechanism during H5N1 influenza virus infection

    OpenAIRE

    Zou, Qiang; Wu, Bing; Xue, Jia; Fan, Xiaoxu; Feng, Congcong; Geng, Shuang; Wang, Ming; Wang, Bin

    2013-01-01

    Although Treg-cell-mediated suppression during infection or autoimmunity has been described, functions of Treg cells during highly pathogenic avian influenza virus infection remain poorly characterized. Here we found that in Foxp3-GFP transgenic mice, CD8+ Foxp3+ Treg cells, but not CD4+ Foxp3+ Treg cells, were remarkably induced during H5N1 infection. In addition to expressing CD25, the CD8+ Foxp3+ Treg cells showed a high level of GITR and produced IL-10. In an adoptive transfer model, CD8+...

  6. Upregulation of chemokine transcriptive levels induced by avian H5N1 and human H1N1 influenza viruses in mouse microglia and astrocytes%流感病毒H1N1和H5N1感染小鼠小胶质细胞与星形胶质细胞诱导趋化因子转录水平上调

    Institute of Scientific and Technical Information of China (English)

    王革非; 李卫中; 张衡; 曾俊; 张丹桂; 陈幼莹; 陈小璇; 李康生

    2010-01-01

    目的:探讨胶质细胞感染流感病毒后的天然免疫反应,检测流感病毒H1N1和H5N1体外感染小鼠小胶质细胞和星形胶质细胞,是否会诱导胶质细胞趋化因子转录水平的变化及其规律.方法:从新生小鼠大脑皮质分离培养神经胶质细胞,并进一步纯化小胶质细胞和星形胶质细胞,经纯度鉴定后,用感染复数为2的流感病毒H1N1和H5N1进行体外感染,8小时后用免疫荧光检测流感病毒核蛋白(NP)的表达,以确认感染细胞比例.在感染早期(6小时)和感染中期(24小时)分别提取细胞RNA,检测趋化因子转录水平的变化.结果:分离得到小鼠的小胶质细胞和星形胶质细胞,病毒感染后超过95%的细胞可以被感染,感染后的小胶质细胞与星形胶质细胞的CCI-3、CCL-5、CXCL-2、CXCL-9和CXCL-10的转录水平发生不同程度的上调,其中CXCL-10的上调幅度最为明显,禽流感病毒H5N1感染能诱导更强烈的上调反应.结论:流感病毒H1N1和H5N1感染小鼠小胶质细胞与星形胶质细胞,可诱导趋化因子转录水平上调.

  7. Glycyrrhizin exerts antioxidative effects in H5N1 influenza A virus-infected cells and inhibits virus replication and pro-inflammatory gene expression.

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    Martin Michaelis

    Full Text Available Glycyrrhizin is known to exert antiviral and anti-inflammatory effects. Here, the effects of an approved parenteral glycyrrhizin preparation (Stronger Neo-Minophafen C were investigated on highly pathogenic influenza A H5N1 virus replication, H5N1-induced apoptosis, and H5N1-induced pro-inflammatory responses in lung epithelial (A549 cells. Therapeutic glycyrrhizin concentrations substantially inhibited H5N1-induced expression of the pro-inflammatory molecules CXCL10, interleukin 6, CCL2, and CCL5 (effective glycyrrhizin concentrations 25 to 50 µg/ml but interfered with H5N1 replication and H5N1-induced apoptosis to a lesser extent (effective glycyrrhizin concentrations 100 µg/ml or higher. Glycyrrhizin also diminished monocyte migration towards supernatants of H5N1-infected A549 cells. The mechanism by which glycyrrhizin interferes with H5N1 replication and H5N1-induced pro-inflammatory gene expression includes inhibition of H5N1-induced formation of reactive oxygen species and (in turn reduced activation of NFκB, JNK, and p38, redox-sensitive signalling events known to be relevant for influenza A virus replication. Therefore, glycyrrhizin may complement the arsenal of potential drugs for the treatment of H5N1 disease.

  8. NP基因特异性干扰RNA抑制H5N1高致病性禽流感病毒复制的研究%Inhibition of highly pathogenic avian influenza virus (H5NI) production by small interfering RNA specific for the NP gene

    Institute of Scientific and Technical Information of China (English)

    张伟; 王承宇; 杨松涛; 高玉伟; 夏成柱

    2009-01-01

    Objective In this study, three siRNAs targeting the nucleoprotein (NP) gene of highly pathogenic avian influenza virus ( HPAIV) H5N1 were designed and evaluated for their ability to inhibit HPAIV replication in vitro. Methods In accordance with siRNA design principles, we designed three siRNAs targeting the NP gene of HSN1 HPAIV and we constructed expression plasmids (ps-NP732, ps-NP863, and ps-NP1344). To evaluate their potential antiviral effect in MDCK cells, virus titer assay, real-time PCR, indirect immunofluorescence assay, and Western blot were carried out. Results Among three siRNAs, ps-NP863 significantly inhibited HPAIV replication, and the viral replication in the ps-NP863-treated cells was 31-fold lower than that of the control; the results of real-time PCR, indirect immunofluorescence assay, and Western blot coincided with those of the virus titer assay. However, ps-NP732 and ps-NP1344 had no ability to inhibit HPAIV replication. Conclusion In this study, ps-NP863 significantly inhibited H5N1 HPAIV replication, and this finding might have significant implications for the use of siRNA in prophylaxis and treatment of influenza virus infection.%目的 设计针对H5N1高致病性禽流感病毒(HPAIV)核蛋白(NP)基因的干扰RNA(siRNA),研究其在细胞水平抑制病毒复制的效果. 方法 根据siRNA设计原则,设计并合成3对靶向HPAIV NP基因的siRNA,构建表达性质粒(ps-NP732、ps-NP863、ps-NP1344),分别转染MDCK细胞并攻毒,通过病毒滴度测定、real-time PCR、间接免疫荧光试验和Western blot,检测siRNA抑制AIV复制的效果. 结果 设计的3对siRNA中,ps-NP863明显抑制AIV复制,病毒滴度与对照组相比降低31倍,real-time PCR、间接免疫荧光试验、Western blot结果与病毒滴度测定结果相符,而ps-NP732和ps-NP1344无抑制AIV复制作用. 结论 构建的ps-NP863可显著抑制HPAIV复制,为开发抗AIV治疗制剂和动物机体抗AIV研究莫定了基础.

  9. 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.

  10. Avian Influenza

    OpenAIRE

    Tsung-Zu Wu; Li-Min Huang

    2005-01-01

    Influenza is an old disease but remains vital nowadays. Three types of influenza viruses,namely A, B, C, have been identified; among them influenza A virus has pandemic potential.The first outbreak of human illness due to avian influenza virus (H5N1) occurred in1997 in Hong Kong with a mortality of 30%. The most recent outbreak of the avian influenzaepidemic has been going on in Asian countries since 2003. As of March 2005, 44 incidentalhuman infections and 32 deaths have been documented. Hum...

  11. 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

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    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. Preclinical evaluation of a replication-deficient intranasal DeltaNS1 H5N1 influenza vaccine.

    Directory of Open Access Journals (Sweden)

    Julia Romanova

    Full Text Available BACKGROUND: We developed a novel intranasal influenza vaccine approach that is based on the construction of replication-deficient vaccine viruses that lack the entire NS1 gene (DeltaNS1 virus. We previously showed that these viruses undergo abortive replication in the respiratory tract of animals. The local release of type I interferons and other cytokines and chemokines in the upper respiratory tract may have a "self-adjuvant effect", in turn increasing vaccine immunogenicity. As a result, DeltaNS1 viruses elicit strong B- and T- cell mediated immune responses. METHODOLOGY/PRINCIPAL FINDINGS: We applied this technology to the development of a pandemic H5N1 vaccine candidate. The vaccine virus was constructed by reverse genetics in Vero cells, as a 5:3 reassortant, encoding four proteins HA, NA, M1, and M2 of the A/Vietnam/1203/04 virus while the remaining genes were derived from IVR-116. The HA cleavage site was modified in a trypsin dependent manner, serving as the second attenuation factor in addition to the deleted NS1 gene. The vaccine candidate was able to grow in the Vero cells that were cultivated in a serum free medium to titers exceeding 8 log(10 TCID(50/ml. The vaccine virus was replication deficient in interferon competent cells and did not lead to viral shedding in the vaccinated animals. The studies performed in three animal models confirmed the safety and immunogenicity of the vaccine. Intranasal immunization protected ferrets and mice from being infected with influenza H5 viruses of different clades. In a primate model (Macaca mulatta, one dose of vaccine delivered intranasally was sufficient for the induction of antibodies against homologous A/Vietnam/1203/04 and heterologous A/Indonesia/5/05 H5N1 strains. CONCLUSION/SIGNIFICANCE: Our findings show that intranasal immunization with the replication deficient H5N1 DeltaNS1 vaccine candidate is sufficient to induce a protective immune response against H5N1 viruses. This approach

  15. The Creation of a Contagious H5N1 Influenza Virus: Implications for the Education of Life Scientists.

    Science.gov (United States)

    Novossiolova, Tatyana; Minehata, Masamichi; Dando, Malcolm

    2012-01-01

    The paper contends that the ongoing controversy surrounding the creation of a contagious H5N1 influenza virus has already exposed the severe limitations of the possibility of preventing the hostile misuse of the life sciences by dint of oversight of proposals and publications. It further argues that in order to prevent the potential wholesale militarisation of the life sciences, it is essential that life scientists become aware of their responsibilities within the context of the Biological and Toxin Weapons Convention (BTWC) and actively contribute their expertise to strengthening the biological weapons non-proliferation regime .

  16. The Creation of a Contagious H5N1 Influenza Virus: Implications for the Education of Life Scientists

    Directory of Open Access Journals (Sweden)

    Tatyana Novossiolova

    2012-07-01

    Full Text Available 'The paper contends that the ongoing controversy surrounding the creation of a contagious H5N1 influenza virus has already exposed the severe limitations of the possibility of preventing the hostile misuse of the life sciences by dint of oversight of proposals and publications. It further argues that in order to prevent the potential wholesale militarisation of the life sciences, it is essential that life scientists become aware of their responsibilities within the context of the Biological and Toxin Weapons Convention (BTWC and actively contribute their expertise to strengthening the biological weapons non-proliferation regime .'

  17. 14-Deoxy-11,12-dehydroandrographolide exerts anti-influenza A virus activity and inhibits replication of H5N1 virus by restraining nuclear export of viral ribonucleoprotein complexes.

    Science.gov (United States)

    Cai, Wentao; Li, Yongtao; Chen, Sunrui; Wang, Mengli; Zhang, Anding; Zhou, Hongbo; Chen, Huanchun; Jin, Meilin

    2015-06-01

    The highly pathogenic avian influenza H5N1 virus has become a worldwide public health threat, and current antiviral therapies have limited activity against the emerging, resistant influenza viruses. Therefore, effective drugs with novel targets against influenza A viruses, H5N1 strains in particular, should be developed. In the present study, 14-deoxy-11,12-dehydroandrographolide (DAP), a major component of the traditional Chinese medicine Andrographis paniculata, exerted potent anti-influenza A virus activity against A/chicken/Hubei/327/2004 (H5N1), A/duck/Hubei/XN/2007 (H5N1), A/PR/8/34 (H1N1), A/NanChang/08/2010 (H1N1) and A/HuNan/01/2014 (H3N2) in vitro. To elucidate the underlying mechanisms, a series of experiments was conducted using A/chicken/Hubei/327/2004 (H5N1) as an example. Our results demonstrated that DAP strongly inhibited H5N1 replication by reducing the production of viral nucleoprotein (NP) mRNA, NP and NS1proteins, whereas DAP had no effect on the absorption and release of H5N1 towards/from A549 cells. DAP also effectively restrained the nuclear export of viral ribonucleoprotein (vRNP) complexes. This inhibitory effect ought to be an important anti-H5N1 mechanism of DAP. Meanwhile, DAP significantly reduced the upregulated expression of all the tested proinflammatory cytokines (TNF-α, IL-6, IL-8, IFN-α, IL-1β and IFN-β) and chemokines (CXCL-10 and CCL-2) stimulated by H5N1. Overall results suggest that DAP impairs H5N1 replication at least in part by restraining nuclear export of vRNP complexes, and the inhibition of viral replication leads to a subsequent decrease of the intense proinflammatory cytokine/chemokine expression. In turn, the effect of modification of the host excessive immune response may contribute to overcoming H5N1. To our knowledge, this study is the first to reveal the antiviral and anti-inflammatory activities of DAP in vitro against H5N1 influenza A virus infection. PMID:25800824

  18. 恒河猴感染H5N1禽流感病毒后肺组织病理变化及病毒分布%Distribution of influenza A (H5N1) virus and pathological lesions in major organ tissues of experimentally infected rhesus macaques

    Institute of Scientific and Technical Information of China (English)

    赖天文; 邓少嫦; 吴东; 黎东明; 陈敏; 吕莹莹; 张钰; 黄韧; 吴斌

    2014-01-01

    Objective To investigate the pathological changes and viral invasion in the main organs of rhesus macaques after experimental infection with H5N1 virus.Methods The rhesus macaques were infected with H5N1 virus (AF148678/ACGoose/Guangdong/11961H5N1) by nasal inoculation under anesthesia.One rhesus macaque was killed respectively at 1,3,6,14 days after infection.The pathologic changes of the main organs were observed using HE staining and the characteristics of the viral invasion in the body were analyzed using viral isolation,RT-PCR andimmunohistochemistry.Results The influenza virus replicated only in the lung tissues characterized by diffuse alveolar damage in the infected rhesus macaques,mainly involving alveolar epithelial cells and pulmonary macrophages.The pathological changes showed 3 phases including exudative inflammation,hyperplasia and fibrosis.Extra-pulmonary organs also showed different degree of pathological changes such as degeneration and necrosis,but virus was not isolated in the corresponding organs.Conclusions Acute diffuse lung injury was a central part of the pathogenesis in H5N1 avian influenza virus infection.The lung was the main target organ in H5N1 viral infection,and H5N1 virus cannot replicate in other organs,which may be one of the obstacles to H5N1 viral transmission from person to person.%目的 探讨恒河猴感染H5N1病毒后肺组织病理变化及病毒分布特点.方法 在麻醉状态下对4只雄性恒河猴经鼻部滴入H5N1禽流感病毒(AF148678/ACGoose/Guangdong/11961H5N1),在染毒后第1、3、6及14天分别剖杀1只恒河猴.HE染色观察主要组织器官的病理变化,应用实时荧光(RT)-PCR及免疫组织化学方法分析H5N1禽流感病毒侵袭机体后肺及其他主要器官的病理改变及病毒分布情况.结果 恒河猴感染H5N1禽流感病毒后,病毒仅在肺组织复制,主要侵犯肺泡上皮细胞和肺巨噬细胞,表现为弥漫性肺泡损伤,先后经历渗出期、增生期和纤

  19. 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.

  20. Immunization with live nonpathogenic H5N3 duck influenza virus protects chickens against highly pathogenic H5N1 virus.

    Science.gov (United States)

    Gambaryan, A S; Boravleva, E Y; Lomakina, N F; Kropotkina, E A; Gordeychuk, I V; Chvala, I A; Drygin, V V; Klenk, H-D; Matrosovich, M N

    2016-01-01

    Development of an effective, broadly-active and safe vaccine for protection of poultry from H5N1 highly pathogenic avian influenza viruses (HPAIVs) remains an important practical goal. In this study we used a low pathogenic wild aquatic bird virus isolate А/duck/Moscow/4182/2010 (H5N3) (dk/4182) as a live candidate vaccine. We compared this virus with four live 1:7 reassortant anti-H5N1 candidate vaccine viruses with modified hemagglutinin from either A/Vietnam/1203/04 (H5N1) or A/Kurgan/3/05 (H5N1) and the rest of the genes from either H2N2 cold-adapted master strain A/Leningrad/134/17/57 (rVN-Len and rKu-Len) or H6N2 virus A/gull/Moscow/3100/2006 (rVN-gull and rKu-gull). The viruses were tested in parallel for pathogenicity, immunogenicity and protective effectiveness in chickens using aerosol, intranasal and oral routes of immunization. All five viruses showed zero pathogenicity indexes in chickens. Viruses rVN-gull and rKu-gull were immunogenic and protective, but they were insufficiently attenuated and caused significant mortality of 1-day-old chickens. The viruses with cold-adapted backbones (rVN-Len and rKu-Len) were completely nonpathogenic, but they were significantly less immunogenic and provided lower protection against lethal challenge with HPAIV A/Chicken/Kurgan/3/05 (H5N1) as compared with three other vaccine candidates. Unlike other four viruses, dk/4182 was both safe and highly immunogenic in chickens of any age regardless of inoculation route. Single administration of 106 TCID50 of dk/4182 virus via drinking water provided complete protection of 30-days-old chickens from 100 LD50 of the challenge virus. Our results suggest that low pathogenic viruses of wild aquatic birds can be used as safe and effective live poultry vaccines against highly pathogenic avian viruses. PMID:27640442

  1. Avian influenza – Review

    OpenAIRE

    Öner, Ahmet Faik

    2007-01-01

    Recent spread of avian influenza A H5N1 virus to poultry and wild birds has increased the threat of human infections with H5N1 virus worldwide In this review the epidemiology virolgy clinical and laboratory characteristics and management of avian influenza is described The virus has demonsrated considerable pandemic potential and is the most likely candidate of next pandemic threat For pandemic preparedness stockpiling antiviral agents and vaccination are the most important intervention measu...

  2. LABEL: fast and accurate lineage assignment with assessment of H5N1 and H9N2 influenza A hemagglutinins.

    Directory of Open Access Journals (Sweden)

    Samuel S Shepard

    Full Text Available The evolutionary classification of influenza genes into lineages is a first step in understanding their molecular epidemiology and can inform the subsequent implementation of control measures. We introduce a novel approach called Lineage Assignment By Extended Learning (LABEL to rapidly determine cladistic information for any number of genes without the need for time-consuming sequence alignment, phylogenetic tree construction, or manual annotation. Instead, LABEL relies on hidden Markov model profiles and support vector machine training to hierarchically classify gene sequences by their similarity to pre-defined lineages. We assessed LABEL by analyzing the annotated hemagglutinin genes of highly pathogenic (H5N1 and low pathogenicity (H9N2 avian influenza A viruses. Using the WHO/FAO/OIE H5N1 evolution working group nomenclature, the LABEL pipeline quickly and accurately identified the H5 lineages of uncharacterized sequences. Moreover, we developed an updated clade nomenclature for the H9 hemagglutinin gene and show a similarly fast and reliable phylogenetic assessment with LABEL. While this study was focused on hemagglutinin sequences, LABEL could be applied to the analysis of any gene and shows great potential to guide molecular epidemiology activities, accelerate database annotation, and provide a data sorting tool for other large-scale bioinformatic studies.

  3. Assessment of the removal and inactivation of influenza viruses H5N1 and H1N1 by drinking water treatment.

    Science.gov (United States)

    Lénès, Dorothée; Deboosere, Nathalie; Ménard-Szczebara, Florence; Jossent, Jérôme; Alexandre, Virginie; Machinal, Claire; Vialette, Michèle

    2010-04-01

    Since 2003, there has been significant concern about the possibility of an outbreak of avian influenza virus subtype H5N1. Moreover, in the last few months, a pandemic of a novel swine-origin influenza A virus, namely A(H1N1), has already caused hundreds of thousands of human cases of illness and thousands of deaths. As those viruses could possibly contaminate water resources through wild birds excreta or through sewage, the aim of our work was to find out whether the treatment processes in use in the drinking water industry are suitable for eradicating them. The effectiveness of physical treatments (coagulation-flocculation-settling, membrane ultrafiltration and ultraviolet) was assessed on H5N1, and that of disinfectants (monochloramine, chlorine dioxide, chlorine, and ozone) was established for both the H5N1 and H1N1 viruses. Natural water samples were spiked with human H5N1/H1N1 viruses. For the coagulation-settling experiments, raw surface water was treated in jar-test pilots with 3 different coagulating agents (aluminum sulfate, ferric chloride, aluminum polychorosulfate). Membrane performance was quantified using a hollow-fiber ultrafiltration system. Ultraviolet irradiation experiments were conducted with a collimated beam that made it possible to assess the effectiveness of various UV doses (25-60 mJ/cm2). In the case of ozone, 0.5 mg/L and 1 mg/L residual concentrations were tested with a contact time of 10 min. Finally, for chlorine, chlorine dioxide and monochloramine treatments, several residual oxidant target levels were tested (from 0.3 to 3 mg/L) with contact times of 5-120 min. The infectivity of the H5N1 and H1N1 viruses in water samples was quantified in cell culture using a microtiter endpoint titration. The impact of coagulation-settling on the H5N1 subtype was quite low and variable. In contrast, ultrafiltration achieved more than a 3-log reduction (and more than a 4-log removal in most cases), and UV treatment was readily effective on its

  4. Assessment of the removal and inactivation of influenza viruses H5N1 and H1N1 by drinking water treatment.

    Science.gov (United States)

    Lénès, Dorothée; Deboosere, Nathalie; Ménard-Szczebara, Florence; Jossent, Jérôme; Alexandre, Virginie; Machinal, Claire; Vialette, Michèle

    2010-04-01

    Since 2003, there has been significant concern about the possibility of an outbreak of avian influenza virus subtype H5N1. Moreover, in the last few months, a pandemic of a novel swine-origin influenza A virus, namely A(H1N1), has already caused hundreds of thousands of human cases of illness and thousands of deaths. As those viruses could possibly contaminate water resources through wild birds excreta or through sewage, the aim of our work was to find out whether the treatment processes in use in the drinking water industry are suitable for eradicating them. The effectiveness of physical treatments (coagulation-flocculation-settling, membrane ultrafiltration and ultraviolet) was assessed on H5N1, and that of disinfectants (monochloramine, chlorine dioxide, chlorine, and ozone) was established for both the H5N1 and H1N1 viruses. Natural water samples were spiked with human H5N1/H1N1 viruses. For the coagulation-settling experiments, raw surface water was treated in jar-test pilots with 3 different coagulating agents (aluminum sulfate, ferric chloride, aluminum polychorosulfate). Membrane performance was quantified using a hollow-fiber ultrafiltration system. Ultraviolet irradiation experiments were conducted with a collimated beam that made it possible to assess the effectiveness of various UV doses (25-60 mJ/cm2). In the case of ozone, 0.5 mg/L and 1 mg/L residual concentrations were tested with a contact time of 10 min. Finally, for chlorine, chlorine dioxide and monochloramine treatments, several residual oxidant target levels were tested (from 0.3 to 3 mg/L) with contact times of 5-120 min. The infectivity of the H5N1 and H1N1 viruses in water samples was quantified in cell culture using a microtiter endpoint titration. The impact of coagulation-settling on the H5N1 subtype was quite low and variable. In contrast, ultrafiltration achieved more than a 3-log reduction (and more than a 4-log removal in most cases), and UV treatment was readily effective on its

  5. Spatial and temporal association of outbreaks of H5N1 influenza virus infection in wild birds with the 0 degrees C isotherm.

    Directory of Open Access Journals (Sweden)

    Leslie A Reperant

    2010-04-01

    Full Text Available Wild bird movements and aggregations following spells of cold weather may have resulted in the spread of highly pathogenic avian influenza virus (HPAIV H5N1 in Europe during the winter of 2005-2006. Waterbirds are constrained in winter to areas where bodies of water remain unfrozen in order to feed. On the one hand, waterbirds may choose to winter as close as possible to their breeding grounds in order to conserve energy for subsequent reproduction, and may be displaced by cold fronts. On the other hand, waterbirds may choose to winter in regions where adverse weather conditions are rare, and may be slowed by cold fronts upon their journey back to the breeding grounds, which typically starts before the end of winter. Waterbirds will thus tend to aggregate along cold fronts close to the 0 degrees C isotherm during winter, creating conditions that favour HPAIV H5N1 transmission and spread. We determined that the occurrence of outbreaks of HPAIV H5N1 infection in waterbirds in Europe during the winter of 2005-2006 was associated with temperatures close to 0 degrees C. The analysis suggests a significant spatial and temporal association of outbreaks caused by HPAIV H5N1 in wild birds with maximum surface air temperatures of 0 degrees C-2 degrees C on the day of the outbreaks and the two preceding days. At locations where waterbird census data have been collected since 1990, maximum mallard counts occurred when average and maximum surface air temperatures were 0 degrees C and 3 degrees C, respectively. Overall, the abundance of mallards (Anas platyrhynchos and common pochards (Aythya ferina was highest when surface air temperatures were lower than the mean temperatures of the region investigated. The analysis implies that waterbird movements associated with cold weather, and congregation of waterbirds along the 0 degrees C isotherm likely contributed to the spread and geographical distribution of outbreaks of HPAIV H5N1 infection in wild birds in

  6. Describing the hexapeptide identity platform between the influenza A H5N1 and Homo sapiens proteomes.

    Science.gov (United States)

    Kanduc, Darja

    2010-01-01

    We searched the primary sequence of influenza A H5N1 polyprotein for hexamer amino acid sequences shared with human proteins using the Protein International Resource database and the exact peptide matching analysis program. We find that the viral polyprotein shares numerous hexapeptides with the human proteome. The human proteins involved in the viral overlap are represented by antigens associated with basic cell functions such as proliferation, development, and differentiation. Of special importance, many human proteins that share peptide sequences with influenza A polyprotein are antigens such as reelin, neurexin I-α, myosin-IXa, Bardet-Biedl syndrome 10 protein, Williams syndrome transcription factor, disrupted in schizophrenia 1 protein, amyotrophic lateral sclerosis 2 chromosomal region candidate gene 17 protein, fragile X mental retardation 2 protein, and jouberin. That is, the viral-vs-human overlap involves human proteins that, when altered, have been reported to be potentially associated with multiple neurological disorders that can include autism, epilepsy, obesity, dystonia, ataxia-telangiectasia, amyotrophic lateral sclerosis, sensorineural deafness, sudden infant death syndrome, Charcot-Marie-Tooth disease, and myelination. The present data are discussed as a possible molecular basis for understanding influenza A viral escape from immunosurveillance and for defining anti-influenza immune-therapeutic approaches devoid of collateral adverse events. PMID:20859452

  7. Describing the hexapeptide identity platform between the influenza A H5N1 and Homo sapiens proteomes

    Directory of Open Access Journals (Sweden)

    Darja Kanduc

    2010-09-01

    Full Text Available Darja KanducDepartment of Biochemistry and Molecular Biology, University of Bari, ItalyAbstract: We searched the primary sequence of influenza A H5N1 polyprotein for hexamer amino acid sequences shared with human proteins using the Protein International Resource database and the exact peptide matching analysis program. We find that the viral polyprotein shares numerous hexapeptides with the human proteome. The human proteins involved in the viral overlap are represented by antigens associated with basic cell functions such as proliferation, development, and differentiation. Of special importance, many human proteins that share peptide sequences with influenza A polyprotein are antigens such as reelin, neurexin I-a, myosin-IXa, Bardet–Biedl syndrome 10 protein, Williams syndrome transcription factor, disrupted in schizophrenia 1 protein, amyotrophic lateral sclerosis 2 chromosomal region candidate gene 17 protein, fragile X mental retardation 2 protein, and jouberin. That is, the viral-vs-human overlap involves human proteins that, when altered, have been reported to be potentially associated with multiple neurological disorders that can include autism, epilepsy, obesity, dystonia, ataxia–telangiectasia, amyotrophic lateral sclerosis, sensorineural deafness, sudden infant death syndrome, Charcot-Marie-Tooth disease, and myelination. The present data are discussed as a possible molecular basis for understanding influenza A viral escape from immunosurveillance and for defining anti-influenza immune-therapeutic approaches devoid of collateral adverse events.Keywords: peptide sharing, neurological disorders, host-pathogen relationships, viral escape from immunosurveillance

  8. Production of inactivated influenza H5N1 vaccines from MDCK cells in serum-free medium.

    Directory of Open Access Journals (Sweden)

    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.

  9. Molecular Determinants of Virulence and Stability of a Reporter-Expressing H5N1 Influenza A Virus

    OpenAIRE

    Zhao, Dongming; Fukuyama, Satoshi; Yamada, Shinya; Lopes, Tiago J. S.; Maemura, Tadashi; Katsura, Hiroaki; Ozawa, Makoto; Watanabe, Shinji; Neumann, Gabriele; Kawaoka, Yoshihiro

    2015-01-01

    We previously reported that an H5N1 virus carrying the Venus reporter gene, which was inserted into the NS gene segment from the A/Puerto Rico/8/1934(H1N1) virus (Venus-H5N1 virus), became more lethal to mice, and the reporter gene was stably maintained after mouse adaptation compared with the wild-type Venus-H5N1 (WT-Venus-H5N1) virus. However, the basis for this difference in virulence and Venus stability was unclear. Here, we investigated the molecular determinants behind this virulence an...

  10. Design, assembly, and validation of a nose-only inhalation exposure system for studies of aerosolized viable influenza H5N1 virus in ferrets

    Directory of Open Access Journals (Sweden)

    Hamilton Sara B

    2010-06-01

    Full Text Available Abstract Background The routes by which humans acquire influenza H5N1 infections have not been fully elucidated. Based on the known biology of influenza viruses, four modes of transmission are most likely in humans: aerosol transmission, ingestion of undercooked contaminated infected poultry, transmission by large droplets and self-inoculation of the nasal mucosa by contaminated hands. In preparation of a study to resolve whether H5N1 viruses are transmissible by aerosol in an animal model that is a surrogate for humans, an inhalation exposure system for studies of aerosolized H5N1 viruses in ferrets was designed, assembled, and validated. Particular attention was paid towards system safety, efficacy of dissemination, the viability of aerosolized virus, and sampling methodology. Results An aerosol generation and delivery system, referred to as a Nose-Only Bioaerosol Exposure System (NBIES, was assembled and function tested. The NBIES passed all safety tests, met expected engineering parameters, required relatively small quantities of material to obtain the desired aerosol concentrations of influenza virus, and delivered doses with high-efficacy. Ferrets withstood a mock exposure trial without signs of stress. Conclusions The NBIES delivers doses of aerosolized influenza viruses with high efficacy, and uses less starting material than other similar designs. Influenza H5N1 and H3N2 viruses remain stable under the conditions used for aerosol generation and sample collection. The NBIES is qualified for studies of aerosolized H5N1 virus.

  11. HETEROSUBTYPIC IMMUNE RESPONSE AND CROSS-PROTECTION AGAINST A HIGHLY PATHOGENIC A (H5N1 INFLUENZA VIRUS IN MICE IMMUNIZED WITH COLD-ADAPTED A/LENINGRAD/134/17/57 (H2N2 INFLUENZA VIRUS

    Directory of Open Access Journals (Sweden)

    A. R. Rekstin

    2005-01-01

    Full Text Available While investigating the efficacy of an H5N2 ca reassortant vaccine candidate in protecting against a lethal challenge with a highly pathogenic (HP H5N1 virus in the mouse model, we observed a degree of cross-protection provided by the ca Len/17 (H2N2 virus itself. 80% of mice administered a high dose of attenuated Len/17 vaccine intranasally (i.n. survived after a lethal challenge with A/Hong Kong/483/97 H5N1 virus. Therefore, we investigated the basis of the cross- reactive immunity between H2N2 and H5N1 viruses that may have contributed to recovery from lethal HK/ 483 virus infection. Sera from mice immunized i.n. with Len/17 did not cross-react with HK/483 virus in neutralization or hemagglutination-inhibition assays, however IgG and IgA antibodies that cross-reacted with the hemagglutinin and neuraminidase of H5N1 1997 viruses were detected. Spleen cells from mice immunized i.n. with Len/17 vaccine showed enhanced production of IL-2, IL-4, IL-5, IL-10, and IFNγ following in vitro stimulation with inactivated H5N1 virus. Our findings indicate that both cross-reactive humoral and cellular immunity induced by Len/17 H2N2 vaccine may plays a role in recovery from lethal H5N1 virus infection. A better understanding of the mechanisms of heterosubtypic immunity will improve vaccine design against HP avian influenza viruses.

  12. 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.

  13. Proinflammatory cytokine response and viral replication in mouse bone marrow derived macrophages infected with influenza H1N1 and H5N1 viruses.

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    Renee W Y Chan

    Full Text Available The pathogenesis of human influenza H5N1 virus infection remains poorly understood and controversial. Cytokine dysregulation in human infection has been hypothesized to contribute to disease severity. We developed in vitro cultures of mouse bone marrow derived macrophages (BMDMΦ from C57BL/6N mouse to compare influenza A (H5N1 and H1N1 virus replication and pro-inflammatory cytokine and chemokine responses. While both H1N1 and H5N1 viruses infected the mouse bone marrow derived macrophages, only the H1N1 virus had showed evidence of productive viral replication from the infected cells. In comparison with human seasonal influenza H1N1 (A/HK/54/98 and mouse adapted influenza H1N1 (A/WSN/33 viruses, the highly pathogenic influenza H5N1 virus (A/HK/483/97 was a more potent inducer of the chemokine, CXCL 10 (IP-10, while there was not a clear differential TNF-α protein expression pattern. Although human influenza viruses rarely cause infection in mice without prior adaption, the use of in vitro cell cultures of primary mouse cells is of interest, especially given the availability of gene-defective (knock-out mice for specific genes.

  14. PB2 amino acid at position 627 affects replicative efficiency, but not cell tropism, of Hong Kong H5N1 influenza A viruses in mice

    International Nuclear Information System (INIS)

    A single amino acid substitution, from glutamic acid to lysine at position 627 of the PB2 protein, converts a nonlethal H5N1 influenza A virus isolated from a human to a lethal virus in mice. In contrast to the nonlethal virus, which replicates only in respiratory organs, the lethal isolate replicates in a variety of organs, producing systemic infection. Despite a clear difference in virulence and organ tropism between the two viruses, it remains unknown whether the dissimilarity is a result of differences in cell tropism or the reduced replicative ability of the nonlethal virus in mouse cells in general. To determine how this single amino acid change affects virulence and organ tropism in mice, we investigated the growth kinetics of the two H5N1 viruses both in vitro and in vivo. The identity of the PB2 amino acid at position 627 did not appreciably affect viral replicative efficiency in chicken embryo fibroblasts and a quail cell line; however, viruses with lysine at this position instead of glutamic acid grew better in the different mouse cells tested. When the effect of this substitution was investigated in mice, all of the test viruses showed the same cell tropism, but infection by viruses containing lysine at position 627 spread more rapidly than those viruses containing glutamic acid at this position. Further analysis showed a difference in local immune responses: neutrophil infiltration in lungs infected with viruses containing lysine at position 627 persisted longer than that associated with viruses lacking a glutamic acid substitution. Our data indicate that the amino acid at position 627 of the PB2 protein determines the efficiency of viral replication in mouse (not avian) cells, but not tropism among cells in different mouse organs. The presence of lysine leads to more aggressive viral replication, overwhelming the host's defense mechanisms and resulting in high mortality rates in mice

  15. 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

  16. Safety, humoral and cell mediated immune responses to two formulations of an inactivated, split-virion influenza A/H5N1 vaccine in children.

    Directory of Open Access Journals (Sweden)

    Tawee Chotpitayasunondh

    Full Text Available BACKGROUND: Highly pathogenic influenza A/H5N1 has caused outbreaks in wild birds and poultry in Asia, Africa and Europe. It has also infected people, especially children, causing severe illness and death. Although the virus shows limited ability to transmit between humans, A/H5N1 represents a potential source of the next influenza pandemic. This study assesses the safety and immunogenicity of aluminium hydroxide adjuvanted (Al and non adjuvanted influenza A/Vietnam/1194/2004 NIBRG-14 (H5N1 vaccine in children. METHODS AND FINDINGS: In a Phase II, open, randomised, multicentre trial 180 children aged 6 months to 17 years received two injections, 21 days apart, of vaccine containing either: 30 microg haemagglutinin (HA with adjuvant (30 microg+Al or 7.5 microg HA without adjuvant. An additional 60 children aged 6-35 months received two "half dose" injections (ie 15 microg+Al or 3.8 microg. Safety was followed for 21 days after vaccination. Antibody responses were assessed 21 days after each injection and cellular immune responses were explored. Vaccination appeared well tolerated in all age groups. The 30 microg+Al formulation was more immunogenic than 7.5 microg in all age groups: in these two groups 79% and 46% had haemagglutinination inhibition antibody titres > or =32 (1/dil. Among 6-35 month-olds, the full doses were more immunogenic than their half dose equivalents. Vaccination induced a predominantly Th2 response against H5 HA. CONCLUSIONS: This influenza A(H5N1 vaccine was well tolerated and immunogenic in children and infants, with Al adjuvant providing a clear immunogenic advantage. These results demonstrate that an H5N1 Al-adjuvanted vaccine, previously shown to be immunogenic and safe in adults, can also be used in children, the group most at risk for pandemic influenza.

  17. 感染H5N1病毒恒河猴大脑的病理学观察%The brain pathological observation of infected H5N1 avian flu virus Macaca rhesus

    Institute of Scientific and Technical Information of China (English)

    李文德; 赵维波; 闵凡贵; 张钰; 刘忠华; 黄韧

    2005-01-01

    目的H5N1禽流感病毒与1918年大流感病毒基因序列的高度相似表明该病毒对人类构成巨大威胁,本文主要观察H5N1禽流感病毒对恒河猴大脑影响.方法恒河猴5只,年龄2~3岁,经环甲膜穿刺接毒105TCID 50/ml 7ml,取大脑行苏木精-伊红(HE)染色和免疫组化观察.结果和对照组11号猴比较,实验组猴出现神经元萎缩,噬神经元现象,局部坏死和血管套现象.结论H5N1禽流感病毒导致恒河猴大脑损害,出现非化脓性脑炎,进一步证实了H5N1禽流感病毒对哺乳类日渐适应并且表现出越来越强的神经毒性.在今后的临床治疗中要重视H5N1病毒引起脑炎的预防和治疗.

  18. 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.

  19. Point-of-Use Mixing of Influenza H5N1 Vaccine and MF59 Adjuvant for Pandemic Vaccination Prepar