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Sample records for human avian influenza

  1. Avian Influenza A Virus Infections in Humans

    MedlinePlus

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Submit What's this? Submit Button Past Newsletters Avian Influenza A Virus Infections in Humans Language: English Españ ...

  2. Avian influenza

    MedlinePlus

    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 ...

  3. Avian Influenza

    MedlinePlus

    ... infectious viral disease of birds. Most avian influenza viruses do not infect humans; however some, such as ... often causing no apparent signs of illness. AI viruses can sometimes spread to domestic poultry and cause ...

  4. Avian Influenza (Bird Flu)

    MedlinePlus

    ... this page: About CDC.gov . Avian Influenza H5 Viruses in the United States Updates and Publications Information ... Humans Examples of Human Infections with Avian Influenza Viruses Outbreaks Health Care and Laboratorian Guidance HPAI A ...

  5. Avian Influenza.

    PubMed

    Zeitlin, Gary Adam; Maslow, Melanie Jane

    2005-05-01

    The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate more than 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantining, and disinfection. To prepare for and prevent an increase in human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short-interfering RNAs and new vaccine strategies that use plasmid-based genetic systems, offer promise should a pandemic occur. PMID:15847721

  6. Avian influenza.

    PubMed

    Zeitlin, Gary A; Maslow, Melanie J

    2006-03-01

    The current epidemic of H5N1 highly pathogenic avian influenza in Southeast Asia raises serious concerns that genetic reassortment will result in the next influenza pandemic. There have been 164 confirmed cases of human infection with avian influenza since 1996. In 2004 alone, there were 45 cases of human H5N1 in Vietnam and Thailand, with a mortality rate over 70%. In addition to the potential public health hazard, the current zoonotic epidemic has caused severe economic losses. Efforts must be concentrated on early detection of bird outbreaks with aggressive culling, quarantines, and disinfection. To prepare for and prevent increased human cases, it is essential to improve detection methods and stockpile effective antivirals. Novel therapeutic modalities, including short, interfering RNAs and new vaccine strategies that use plasmid-based genetic systems offer promise, should a pandemic occur. PMID:16566867

  7. Avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is a viral infection of birds that varies in severity from asymptomatic infections to mild respiratory and reproductive diseases to an acute, highly fatal systemic disease of chickens, turkeys, guinea fowls, and other avian species. Avian influenza viruses are divided into two ...

  8. Highly Pathogenic Avian Influenza: Intersecting Humans, Animals, and the Environment

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Eurasian-African H5N1 highly pathogenic avian influenza (HPAI) virus has caused an unprecedented epizootic affecting mainly poultry, but has crossed multiple species barriers to infect captive and wild birds, carnivorous mammals and humans. There is still great concern over the continued infecti...

  9. Sialic acid content in human saliva and anti-influenza activity against human and avian influenza viruses.

    PubMed

    Limsuwat, Nattavatchara; Suptawiwat, Ornpreya; Boonarkart, Chompunuch; Puthavathana, Pilaipan; Wiriyarat, Witthawat; Auewarakul, Prasert

    2016-03-01

    It was shown previously that human saliva has higher antiviral activity against human influenza viruses than against H5N1 highly pathogenic avian influenza viruses, and that the major anti-influenza activity was associated with sialic-acid-containing molecules. To further characterize the differential susceptibility to saliva among influenza viruses, seasonal influenza A and B virus, pandemic H1N1 virus, and 15 subtypes of avian influenza virus were tested for their susceptibility to human and chicken saliva. Human saliva showed higher hemagglutination inhibition (HI) and neutralization (NT) titers against seasonal influenza A virus and the pandemic H1N1 viruses than against influenza B virus and most avian influenza viruses, except for H9N2 and H12N9 avian influenza viruses, which showed high HI and NT titers. To understand the nature of sialic-acid-containing anti-influenza factors in human saliva, α2,3- and α2,6-linked sialic acid was measured in human saliva samples using a lectin binding and dot blot assay. α2,6-linked sialic acid was found to be more abundant than α2,3-linked sialic acid, and a seasonal H1N1 influenza virus bound more efficiently to human saliva than an H5N1 virus in a dot blot analysis. These data indicated that human saliva contains the sialic acid type corresponding to the binding preference of seasonal influenza viruses. PMID:26671828

  10. Avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The natural host for avian influenza virus (AIV) is in wild birds, including ducks, gulls, and shorebirds, where the virus causes primarily an enteric infection with little disease. However, AIV can infect a wide variety of host species, and with a certain level of adaptation for the aberrant host ...

  11. Avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) viruses infect domestic poultry and wild birds. In domestic poultry, AI viruses are typically of low pathogenicity (LP) causing subclinical infections, respiratory disease or drops in egg production. However, a few AI viruses cause severe systemic disease with high mortality; i....

  12. AVIAN INFLUENZA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian Influenza (AI) viruses infect domestic poultry and wild birds. In domestic poultry, AI viruses are typically of low pathogenicity (LP) causing subclinical infections, respiratory disease or drops in egg production. However, a few AI viruses cause severe systemic disease with high mortality; ...

  13. [SARS, avian influenza, and human metapneumovirus infection].

    PubMed

    Casas, Inmaculada; Pozo, Francisco

    2005-01-01

    Beginning in the 1950s respiratory viruses have been gradually discovered by isolation in cell cultures The last were the coronaviruses in the 1960s. No new respiratory viruses were discovered until 2001 when human metapneumovirus was found in respiratory specimens from children with bronchiolitis. A year later, in November 2002, severe acute respiratory syndrome (SARS) suddenly appeared as atypical pneumonia. A novel virus belonging to the Coronaviridae family was found to be a cause of this infection. In 2004, a second coronavirus was discovered (CoV-NL63) and in 2005 a third new coronavirus was described (CoV-HKU1). In addition, several subtypes of the influenza A virus, previously known to infect only poultry and wild birds, were recently found to have been directly transmitted to humans. Respiratory infection has been a considerable problem for humans for centuries. Now, in the 21st century, with new associated viruses continuously emerging, it remains an important field for work. PMID:16159544

  14. Avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is type A influenza, which is adapted to an avian host. Although avian influenza has been isolated from numerous avian species, the primary natural hosts for the virus are dabbling ducks, shorebirds, and gulls. The virus can be found world-wide in these species and in o...

  15. Avian influenza: recent developments.

    PubMed

    Capua, Ilaria; Alexander, Dennis J

    2004-08-01

    This paper reviews the worldwide situation regarding avian influenza infections in poultry from 1997 to March 2004. The increase in the number of primary introductions and the scientific data available on the molecular basis of pathogenicity have generated concerns particularly for legislative purposes and for international trade. This has led to a new proposed definition of 'avian influenza' to extend all infections caused by H5 and H7 viruses regardless of their virulence as notifiable diseases, although this has encountered some difficulties in being approved. The paper also reviews the major outbreaks caused by viruses of the H5 or H7 subtype and the control measures applied. The zoonotic aspects of avian influenza, which until 1997 were considered to be of limited relevance in human medicine, are also discussed. The human health implications have now gained importance, both for illness and fatalities that have occurred following natural infection with avian viruses, and for the potential of generating a reassortant virus that could give rise to the next human influenza pandemic. PMID:15370036

  16. BirdFlu2009: Avian Influenza and Human Health. 9-10 September 2009, Oxford, UK.

    PubMed

    Temperton, Nigel

    2009-11-01

    The BirdFlu2009 meeting entitled Avian Influenza and Human Health, held in Oxford, included topics covering new developments in the control of seasonal, avian and swine influenza virus infection, with a focus on the human-animal interface. This conference report highlights selected presentations on sialidase therapy for influenza infection, the use of IVIgs to study antibody diversity and reactivity, detecting oseltamivir carboxylate in waste water, H5N1 infection in Egyptian children, preparedness for an influenza pandemic and an indirect sandwich ELISA to detect H5 avian influenza virus. Investigational drugs discussed include NEX-DAS-181 (NexBio Inc) and MVA-NP-M1 (The Edward Jenner Institute for Vaccine Research). PMID:19844852

  17. Protective avian influenza in ovo vaccination with non-replicating human adenovirus vector

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Protective immunity against avian influenza (AI) virus was elicited in chickens by single dose in ovo vaccination with a replication competent adenovirus (RCA) -free human adenovirus vector (Ad5) encoding an avian AI virus H5 hemagglutinin. Vaccinated chickens were protected against both H5N1 and H5...

  18. Protective avian influenza in ovo vaccination with non-replicating human adenovirus vector.

    PubMed

    Toro, Haroldo; Tang, De-chu C; Suarez, David L; Sylte, Matt J; Pfeiffer, Jennifer; Van Kampen, Kent R

    2007-04-12

    Protective immunity against avian influenza virus was elicited in chickens by single-dose in ovo vaccination with a non-replicating human adenovirus vector encoding an H5N9 avian influenza virus hemagglutinin. Vaccinated chickens were protected against both H5N1 (89% hemagglutinin homology; 68% protection) and H5N2 (94% hemagglutinin homology; 100% protection) highly pathogenic avian influenza virus challenges. This vaccine can be mass-administered using available robotic in ovo injectors which provide a major advantage over current vaccination regimens. In addition, this class of adenovirus-vectored vaccines can be produced rapidly with improved safety since they do not contain any replication-competent adenoviruses. Furthermore, this mode of vaccination is compatible with epidemiological surveys of natural avian influenza virus infections. PMID:17055126

  19. Human Infection with Highly Pathogenic A(H7N7) Avian Influenza Virus, Italy, 2013

    PubMed Central

    Rossini, Giada; Facchini, Marzia; Vaccari, Gabriele; Di Trani, Livia; Di Martino, Angela; Gaibani, Paolo; Vocale, Caterina; Cattoli, Giovanni; Bennett, Michael; McCauley, John W.; Rezza, Giovanni; Moro, Maria Luisa; Rangoni, Roberto; Finarelli, Alba Carola; Landini, Maria Paola; Castrucci, Maria Rita; Donatelli, Isabella

    2014-01-01

    During an influenza A(H7N7) virus outbreak among poultry in Italy during August–September 2013, infection with a highly pathogenic A(H7N7) avian influenza virus was diagnosed for 3 poultry workers with conjunctivitis. Genetic analyses revealed that the viruses from the humans were closely related to those from chickens on affected farms. PMID:25271444

  20. Serological Evidence of Human Infection with Avian Influenza A H7virus in Egyptian Poultry Growers

    PubMed Central

    Gomaa, Mokhtar R.; Kandeil, Ahmed; Kayed, Ahmed S.; Elabd, Mona A.; Zaki, Shaimaa A.; Abu Zeid, Dina; El Rifay, Amira S.; Mousa, Adel A.; Farag, Mohamed M.; McKenzie, Pamela P.; Webby, Richard J.; Ali, Mohamed A.; Kayali, Ghazi

    2016-01-01

    Avian influenza viruses circulate widely in birds, with occasional human infections. Poultry-exposed individuals are considered to be at high risk of infection with avian influenza viruses due to frequent exposure to poultry. Some avian H7 viruses have occasionally been found to infect humans. Seroprevalence of neutralizing antibodies against influenza A/H7N7 virus among poultry-exposed and unexposed individuals in Egypt were assessed during a three-years prospective cohort study. The seroprevalence of antibodies (titer, ≥80) among exposed individuals was 0%, 1.9%, and 2.1% annually while the seroprevalence among the control group remained 0% as measured by virus microneutralization assay. We then confirmed our results using western blot and immunofluorescence assays. Although human infection with H7 in Egypt has not been reported yet, our results suggested that Egyptian poultry growers are exposed to avian H7 viruses. These findings highlight the need for surveillance in the people exposed to poultry to monitor the risk of zoonotic transmission of avian influenza viruses. PMID:27258357

  1. Avian influenza virus in pregnancy.

    PubMed

    Liu, Shelan; Sha, Jianping; Yu, Zhao; Hu, Yan; Chan, Ta-Chien; Wang, Xiaoxiao; Pan, Hao; Cheng, Wei; Mao, Shenghua; Zhang, Run Ju; Chen, Enfu

    2016-07-01

    The unprecedented epizootic of avian influenza viruses, such as H5N1, H5N6, H7N1 and H10N8, has continued to cause disease in humans in recent years. In 2013, another novel influenza A (H7N9) virus emerged in China, and 30% of those patients died. Pregnant women are particularly susceptible to avian influenza and are more likely to develop severe complications and to die, especially when infection occurs in the middle and late trimesters. Viremia is believed to occur infrequently, and thus vertical transmission induced by avian influenza appears to be rare. However, avian influenza increases the risk of adverse pregnancy outcomes, including spontaneous abortion, preterm birth and fatal distress. This review summarises 39 cases of pregnant women and their fetuses from different countries dating back to 1997, including 11, 15 and 13 infections with H7N9, H5N1 and the 2009 pandemic influenza (H1N1), respectively. We analysed the epidemic features, following the geographical, population and pregnancy trimester distributions; underlying diseases; exposure history; medical timelines; human-to-human transmission; pathogenicity and vertical transmission; antivirus treatments; maternal severity and mortality and pregnancy outcome. The common experiences reported in different countries and areas suggest that early identification and treatment are imperative. In the future, vigilant virologic and epidemiologic surveillance systems should be developed to monitor avian influenza viruses during pregnancy. Furthermore, extensive study on the immune mechanisms should be conducted, as this will guide safe, rational immunomodulatory treatment among this high-risk population. Most importantly, we should develop a universal avian influenza virus vaccine to prevent outbreaks of the different subtypes. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27187752

  2. Avian Influenza A (H7N9) Virus

    MedlinePlus

    ... this page: About CDC.gov . Avian Influenza H5 Viruses in the United States Updates and Publications Information ... Humans Examples of Human Infections with Avian Influenza Viruses Outbreaks Health Care and Laboratorian Guidance HPAI A ...

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

    PubMed Central

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

    2007-01-01

    Pandemic influenza virus has its origins in avian influenza viruses. The highly pathogenic avian influenza virus subtype H5N1 is already panzootic in poultry, with attendant economic consequences. It continues to cross species barriers to infect humans and other mammals, often with fatal outcomes. Therefore, H5N1 virus has rightly received attention as a potential pandemic threat. However, it is noted that the pandemics of 1957 and 1968 did not arise from highly pathogenic influenza viruses, and the next pandemic may well arise from a low-pathogenicity virus. The rationale for particular concern about an H5N1 pandemic is not its inevitability but its potential severity. An H5N1 pandemic is an event of low probability but one of high human health impact and poses a predicament for public health. Here, we review the ecology and evolution of highly pathogenic avian influenza H5N1 viruses, assess the pandemic risk, and address aspects of human H5N1 disease in relation to its epidemiology, clinical presentation, pathogenesis, diagnosis, and management. PMID:17428885

  4. A Review of the Antiviral Susceptibility of Human and Avian Influenza Viruses over the Last Decade

    PubMed Central

    Oh, Ding Yuan; Hurt, Aeron C.

    2014-01-01

    Antivirals play an important role in the prevention and treatment of influenza infections, particularly in high-risk or severely ill patients. Two classes of influenza antivirals have been available in many countries over the last decade (2004–2013), the adamantanes and the neuraminidase inhibitors (NAIs). During this period, widespread adamantane resistance has developed in circulating influenza viruses rendering these drugs useless, resulting in the reliance on the most widely available NAI, oseltamivir. However, the emergence of oseltamivir-resistant seasonal A(H1N1) viruses in 2008 demonstrated that NAI-resistant viruses could also emerge and spread globally in a similar manner to that seen for adamantane-resistant viruses. Previously, it was believed that NAI-resistant viruses had compromised replication and/or transmission. Fortunately, in 2013, the majority of circulating human influenza viruses remain sensitive to all of the NAIs, but significant work by our laboratory and others is now underway to understand what enables NAI-resistant viruses to retain the capacity to replicate and transmit. In this review, we describe how the susceptibility of circulating human and avian influenza viruses has changed over the last ten years and describe some research studies that aim to understand how NAI-resistant human and avian influenza viruses may emerge in the future. PMID:24800107

  5. Quail carry sialic acid receptors compatible with binding of avian and human influenza viruses

    PubMed Central

    Wan, Hongquan; Perez, Daniel R.

    2016-01-01

    There is growing evidence that some terrestrial avian species may play a role in the genesis of influenza viruses with pandemic potential. In the present investigation, we examined whether quail, a widespread-farmed poultry, possess the proper characteristics for serving as an intermediate host for the zoonotic transmission of influenza viruses. Using a lectin-based staining based on specific agglutinins, we found that, in addition to the presence of sialic acid α2,3-galactose (SAα2,3-gal) linked receptors, there are abundant sialic acid α2,6-galactose (SAα2,6-gal) linked receptors in quail trachea and intestine. The presence of abundant SAα2,6-gal-linked receptors explains, at least in part, the circulation of avian influenza viruses with human-like receptor specificity in quail. In quail trachea, SAα2,3-gal linked receptors are present primarily in non-ciliated cells, while SAα2,6-gal linked receptors are localized predominantly on the surface of ciliated cells. In quail intestine, both types of receptors were found on epithelial cells as well as in crypts. In a solid-phase overlay binding assay, both avian and human influenza viruses bind to plasma membranes prepared from epithelial cells of quail trachea and intestine, strongly suggesting that these receptors are functional for binding of influenza viruses from different species. Together with previous observations, these results are consistent with the notion that quail could provide an environment for the spread of reassortants between avian and human influenza viruses, thus acting as a potential intermediate host. PMID:16325879

  6. Adaptation of avian influenza A (H6N1) virus from avian to human receptor-binding preference.

    PubMed

    Wang, Fei; Qi, Jianxun; Bi, Yuhai; Zhang, Wei; Wang, Min; Zhang, Baorong; Wang, Ming; Liu, Jinhua; Yan, Jinghua; Shi, Yi; Gao, George F

    2015-06-12

    The receptor-binding specificity of influenza A viruses is a major determinant for the host tropism of the virus, which enables interspecies transmission. In 2013, the first human case of infection with avian influenza A (H6N1) virus was reported in Taiwan. To gather evidence concerning the epidemic potential of H6 subtype viruses, we performed comprehensive analysis of receptor-binding properties of Taiwan-isolated H6 HAs from 1972 to 2013. We propose that the receptor-binding properties of Taiwan-isolated H6 HAs have undergone three major stages: initially avian receptor-binding preference, secondarily obtaining human receptor-binding capacity, and recently human receptor-binding preference, which has been confirmed by receptor-binding assessment of three representative virus isolates. Mutagenesis work revealed that E190V and G228S substitutions are important to acquire the human receptor-binding capacity, and the P186L substitution could reduce the binding to avian receptor. Further structural analysis revealed how the P186L substitution in the receptor-binding site of HA determines the receptor-binding preference change. We conclude that the human-infecting H6N1 evolved into a human receptor preference. PMID:25940072

  7. The role of avian/human-like influenza polymerase genes in the adaptation of influenza viruses to pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Around 1998, reassortment events occurred in pigs in the U.S. which resulted in the transfer of avian and human influenza genes into "classical" H1N1 (cH1N1) swine influenza viruses (SIV) producing novel H3N2, H1N2, H3N1 and reassortant H1N1 (rH1N1) viruses. These novel H3N2, H1N2 and rH1N1 viruses ...

  8. Dynamical analysis of the avian-human influenza epidemic model using the semi-analytical method

    NASA Astrophysics Data System (ADS)

    Jabbari, Azizeh; Kheiri, Hossein; Bekir, Ahmet

    2015-03-01

    In this work, we present a dynamic behavior of the avian-human influenza epidemic model by using efficient computational algorithm, namely the multistage differential transform method(MsDTM). The MsDTM is used here as an algorithm for approximating the solutions of the avian-human influenza epidemic model in a sequence of time intervals. In order to show the efficiency of the method, the obtained numerical results are compared with the fourth-order Runge-Kutta method (RK4M) and differential transform method(DTM) solutions. It is shown that the MsDTM has the advantage of giving an analytical form of the solution within each time interval which is not possible in purely numerical techniques like RK4M.

  9. Avian influenza: an osteopathic component to treatment

    PubMed Central

    Hruby, Raymond J; Hoffman, Keasha N

    2007-01-01

    Avian influenza is an infection caused by the H5N1 virus. The infection is highly contagious among birds, and only a few known cases of human avian influenza have been documented. However, healthcare experts around the world are concerned that mutation or genetic exchange with more commonly transmitted human influenza viruses could result in a pandemic of avian influenza. Their concern remains in spite of the fact that the first United States vaccine against the H5N1 virus was recently approved. Under these circumstances the fear is that a pandemic of avian influenza could result in the kind of mortality that was seen with the Spanish influenza pandemic of 1918–1919, where the number of deaths was estimated to be as high as 40 million people. Retrospective data gathered by the American Osteopathic Association shortly after the 1918–1919 influenza pandemic have suggested that osteopathic physicians (DOs), using their distinctive osteopathic manipulative treatment (OMT) methods, observed significantly lower morbidity and mortality among their patients as compared to those treated by allopathic physicians (MDs) with standard medical care available at the time. In light of the limited prevention and treatment options available, it seems logical that a preparedness plan for the treatment of avian influenza should include these OMT procedures, provided by DOs and other healthcare workers capable of being trained to perform these therapeutic interventions. The purpose of this paper is to discuss the characteristics of avian influenza, describe the success of DOs during the 1918–1919 Spanish influenza pandemic, describe the evidence base for the inclusion of OMT as part of the preparedness plan for the treatment of avian influenza, and describe some of the specific OMT procedures that could be utilized as part of the treatment protocol for avian influenza patients. PMID:17620133

  10. Avian influenza (fowl plague)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) viruses infect domestic poultry and wild birds. In domestic poultry, AI viruses are typically of low pathogenicity (LP) causing subclinical infections, respiratory disease or drops in egg production. However, a few AI viruses cause severe systemic disease with high mortality; ...

  11. FAO-OIE-WHO Joint Technical Consultation on Avian Influenza at the Human-Animal Interface.

    PubMed

    Anderson, Tara; Capua, Ilaria; Dauphin, Gwenaëlle; Donis, Ruben; Fouchier, Ron; Mumford, Elizabeth; Peiris, Malik; Swayne, David; Thiermann, Alex

    2010-05-01

    For the past 10 years, animal health experts and human health experts have been gaining experience in the technical aspects of avian influenza in mostly separate fora. More recently, in 2006, in a meeting of the small WHO Working Group on Influenza Research at the Human Animal Interface (Meeting report available from: http://www.who.int/csr/resources/publications/influenza/WHO_CDS_EPR_GIP_2006_3/en/index.html) in Geneva allowed influenza experts from the animal and public health sectors to discuss together the most recent avian influenza research. Ad hoc bilateral discussions on specific technical issues as well as formal meetings such as the Technical Meeting on HPAI and Human H5N1 Infection (Rome, June, 2007; information available from: http://www.fao.org/avianflu/en/conferences/june2007/index.html) have increasingly brought the sectors together and broadened the understanding of the topics of concern to each sector. The sectors have also recently come together at the broad global level, and have developed a joint strategy document for working together on zoonotic diseases (Joint strategy available from: ftp://ftp.fao.org/docrep/fao/011/ajl37e/ajl37e00.pdf). The 2008 FAO-OIE-WHO Joint Technical Consultation on Avian Influenza at the Human Animal Interface described here was the first opportunity for a large group of influenza experts from the animal and public health sectors to gather and discuss purely technical topics of joint interest that exist at the human-animal interface. During the consultation, three influenza-specific sessions aimed to (1) identify virological characteristics of avian influenza viruses (AIVs) important for zoonotic and pandemic disease, (2) evaluate the factors affecting evolution and emergence of a pandemic influenza strain and identify existing monitoring systems, and (3) identify modes of transmission and exposure sources for human zoonotic influenza infection (including discussion of specific exposure risks by affected countries). A

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

    PubMed Central

    Arai, Yasuha; Kawashita, Norihito; Daidoji, Tomo; Ibrahim, Madiha S.; El-Gendy, Emad M.; Takagi, Tatsuya; Takahashi, Kazuo; Suzuki, Yasuo; Ikuta, Kazuyoshi; Nakaya, Takaaki; Shioda, Tatsuo; Watanabe, Yohei

    2016-01-01

    A major determinant in the change of the avian influenza virus host range to humans is the E627K substitution in the PB2 polymerase protein. However, the polymerase activity of avian influenza viruses with a single PB2-E627K mutation is still lower than that of seasonal human influenza viruses, implying that avian viruses require polymerase mutations in addition to PB2-627K for human adaptation. Here, we used a database search of H5N1 clade 2.2.1 virus sequences with the PB2-627K mutation to identify other polymerase adaptation mutations that have been selected in infected patients. Several of the mutations identified acted cooperatively with PB2-627K to increase viral growth in human airway epithelial cells and mouse lungs. These mutations were in multiple domains of the polymerase complex other than the PB2-627 domain, highlighting a complicated avian-to-human adaptation pathway of avian influenza viruses. Thus, H5N1 viruses could rapidly acquire multiple polymerase mutations that function cooperatively with PB2-627K in infected patients for optimal human adaptation. PMID:27097026

  13. Pathobiology of avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus causes serious disease in a wide variety of birds and mammals. Its natural hosts are wild aquatic birds, in which most infections are unapparent. Avian Influenza (AI) viruses are classified into 16 hemagglutinin (H1-16) and nine neuraminidase (N1-9) subtypes. Each virus has on...

  14. Avian influenza prevention and control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza is one of the most important diseases affecting the poultry industry around the world. Avian Influenza virus (AIV) has a broad host range in birds and mammals, although the natural reservoir is considered to be in wild birds where it typically causes an asymptomatic to mild infectio...

  15. Avian influenza: Vaccination and control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is a viral disease of poultry that remains an economic threat to commercial poultry throughout the world by negatively impacting animal health and trade. Strategies to control avian influenza (AI) virus are developed to prevent, manage or eradicate the virus from the country, re...

  16. Sustained live poultry market surveillance contributes to early warnings for human infection with avian influenza viruses.

    PubMed

    Fang, Shisong; Bai, Tian; Yang, Lei; Wang, Xin; Peng, Bo; Liu, Hui; Geng, Yijie; Zhang, Renli; Ma, Hanwu; Zhu, Wenfei; Wang, Dayan; Cheng, Jinquan; Shu, Yuelong

    2016-01-01

    Sporadic human infections with the highly pathogenic avian influenza (HPAI) A (H5N6) virus have been reported in different provinces in China since April 2014. From June 2015 to January 2016, routine live poultry market (LPM) surveillance was conducted in Shenzhen, Guangdong Province. H5N6 viruses were not detected until November 2015. The H5N6 virus-positive rate increased markedly beginning in December 2015, and viruses were detected in LPMs in all districts of the city. Coincidently, two human cases with histories of poultry exposure developed symptoms and were diagnosed as H5N6-positive in Shenzhen during late December 2015 and early January 2016. Similar viruses were identified in environmental samples collected in the LPMs and the patients. In contrast to previously reported H5N6 viruses, viruses with six internal genes derived from the H9N2 or H7N9 viruses were detected in the present study. The increased H5N6 virus-positive rate in the LPMs and the subsequent human infections demonstrated that sustained LPM surveillance for avian influenza viruses provides an early warning for human infections. Interventions, such as LPM closures, should be immediately implemented to reduce the risk of human infection with the H5N6 virus when the virus is widely detected during LPM surveillance. PMID:27485495

  17. Receptor specificity in human, avian, and equine H2 and H3 influenza virus isolates.

    PubMed

    Connor, R J; Kawaoka, Y; Webster, R G; Paulson, J C

    1994-11-15

    The receptor specificity of 56 H2 and H3 influenza virus isolates from various animal species has been determined to test the relevance of receptor specificity to the ecology of influenza virus. The results show that the receptor specificity of both H2 and H3 isolates evaluated for sialic acid linkage specificity and inhibition of hemagglutination by horse serum correlates with the species of origin, as postulated earlier for H3 strains based on a limited survey of five human, three avian, and one equine strain. Elucidation of the amino acid sequence of several human H2 receptor variants and analysis of known sequences of H2 and H3 isolates revealed that receptor specificity varies in association with an amino acid change at residues 228 in addition to the change at residue 226 previously documented to affect receptor specificity of H3 but not H1 isolates. Residues 226 and 228 are leucine and serine in human isolates, which preferentially bind sialic acid alpha 2,6-galactose beta 1,4-N-acetyl glucosamine (SA alpha 2,6Gal), and glutamine and glycine in avian and equine isolates, which exhibit specificity for sialic acid alpha-2,3-galactose beta-1,3-N-acetyl galactosamine (SA alpha 2,3Gal). The results demonstrate that the correlation of receptor specificity and species of origin is maintained across both H2 and H3 influenza virus serotypes and provide compelling evidence that influenza virus hosts exert selective pressure to maintain the receptor specificity characteristics of strains isolated from that species. PMID:7975212

  18. Sero-prevalence of avian influenza in animals and human in Egypt.

    PubMed

    El-Sayed, A; Prince, A; Fawzy, A; Nadra-Elwgoud; Abdou, M I; Omar, L; Fayed, A; Salem, M

    2013-06-01

    In opposite to most countries, avian influenza virus H5N1 became endemic in Egypt. Since, its first emerge in 2006 in Egypt, the virus could infect different species of birds and animals and even human. Beside the great economic losses to the local poultry industry in Egypt, the virus infected 166 confirmed human cases, 59 cases ended fatally. In the present study, the persistence of the avian influenza in the Egyptian environment was studied. For this purpose, serum samples were collected from human, cattle, buffaloes, sheep, goat, horses, donkeys, swine, sewage rats, stray dogs and stray cats. The sera were collected from Cairo and the surrounding governorates to be examined for the presence of anti-H5N1 antibodies by Haemagglutination Inhibition Test (HI) and ELISA test. Clear differences in the seroprevalence were noticed among different species and also between the results obtained by both techniques indicating the difference in test accuracy. The present data indicate wide spread of the H5N1 virus in the Egyptian environment. PMID:24498821

  19. A generic model of contagious disease and its application to human-to-human transmission of avian influenza.

    SciTech Connect

    Hirsch, Gary B.

    2007-03-01

    Modeling contagious diseases has taken on greater importance over the past several years as diseases such as SARS and avian influenza have raised concern about worldwide pandemics. Most models developed to consider projected outbreaks have been specific to a single disease. This paper describes a generic System Dynamics contagious disease model and its application to human-to-human transmission of a mutant version of avian influenza. The model offers the option of calculating rates of new infections over time based either on a fixed ''reproductive number'' that is traditional in contagious disease models or on contact rates for different sub-populations and likelihood of transmission per contact. The paper reports on results with various types of interventions. These results suggest the potential importance of contact tracing, limited quarantine, and targeted vaccination strategies as methods for controlling outbreaks, especially when vaccine supplies may initially be limited and the efficacy of anti-viral drugs uncertain.

  20. Influenza vaccines for avian species.

    PubMed

    Kapczynski, Darrell R; Swayne, David E

    2009-01-01

    Beginning in Southeast Asia in 2003, a multinational epizootic outbreak of H5N1 highly pathogenic avian influenza (HPAI) was identified in commercial poultry and wild bird species. This lineage, originally identified in Southern China in 1996 and then Hong Kong in 1997, caused severe morbidity and mortality in many bird species, was responsible for considerable economic losses via trade restrictions, and crossed species barriers (including its recovery from human cases). To date, these H5N1 HPAI viruses have been isolated in European, Middle Eastern, and African countries, and are considered endemic in many areas where regulatory control and different production sectors face substantial hurdles in controlling the spread of this disease. While control of avian influenza (AI) virus infections in wild bird populations may not be feasible at this point, control and eradiation of AI from commercial, semicommercial, zoo, pet, and village/backyard birds will be critical to preventing events that could lead to the emergence of epizootic influenza virus. Efficacious vaccines can help reduce disease, viral shedding, and transmission to susceptible cohorts. However, only when vaccines are used in a comprehensive program including biosecurity, education, culling, diagnostics and surveillance can control and eradication be considered achievable goals. In humans, protection against influenza is provided by vaccines that are chosen based on molecular, epidemiologic, and antigenic data. In poultry and other birds, AI vaccines are produced against a specific hemagglutinin subtype of AI, and use is decided by government and state agricultural authorities based on risk and economic considerations, including the potential for trade restrictions. In the current H5N1 HPAI epizootic, vaccines have been used in a variety of avian species as a part of an overall control program to aid in disease management and control. PMID:19768403

  1. Avian influenza in Mexico.

    PubMed

    Villarreal, C

    2009-04-01

    The outbreak of highly pathogenic avian influenza (HPAI) H5N2 in Mexico in 1994 led to a clear increase in biosecurity measures and improvement of intensive poultry production systems. The control and eradication measures implemented were based on active surveillance, disease detection, depopulation of infected farms and prevention of possible contacts (identified by epidemiological investigations), improvement of biosecurity measures, and restriction of the movement of live birds, poultry products, by-products and infected material. In addition, Mexico introduced a massive vaccination programme, which resulted in the eradication of HPAI in a relatively short time in two affected areas that had a high density of commercial poultry. PMID:19618630

  2. First human case of avian influenza A (H5N6) in Yunnan province, China

    PubMed Central

    He, Jibo

    2015-01-01

    Objective: To report clinical, virological, and epidemiological features of the first death caused by a H5N6 avian influenza virus in Yunnan Province, China. Method: The case was described in clinical expression, chest radiography, blood test and treatment. Real-time RT-PCR was used to detect H5N6 virus RNA in clinical and environment samples. Epidemiological investigation was performed including case exposure history determinant, close contacts follow up, and environment sample collection. Results: The patient initially developed sore throat and coughs on 27 January 2015. The disease progressed to severe pneumonia, multiple organ dysfunction syndrome, and acute respiratory distress syndrome. And the patient died on 6 February. A highly pathogenic avian influenza A H5N6 virus was isolated from the tracheal aspirate specimen of the patient. The viral genome analyses revealed that the H5 hemmagglutinin gene belongs to 2.3.4.4 clade. Epidemiological investigation showed that the patient had exposure to wild bird. All close contacts of the patient did not present the same disease in seven consecutive days. A high H5 positive rate was detected in environmental samples from local live poultry markets. Conclusion: The findings suggest that studies on the source of the virus, transmission models, serologic investigations, vaccines, and enhancing surveillance in both humans and birds are necessary. PMID:27489694

  3. A human-infecting H10N8 influenza virus retains a strong preference for avian-type receptors.

    PubMed

    Zhang, Heng; de Vries, Robert P; Tzarum, Netanel; Zhu, Xueyong; Yu, Wenli; McBride, Ryan; Paulson, James C; Wilson, Ian A

    2015-03-11

    Recent avian-origin H10N8 influenza A viruses that have infected humans pose a potential pandemic threat. Alterations in the viral surface glycoprotein, hemagglutinin (HA), typically are required for influenza A viruses to cross the species barrier for adaptation to a new host, but whether H10N8 contains adaptations supporting human infection remains incompletely understood. We investigated whether H10N8 HA can bind human receptors. Sialoside glycan microarray analysis showed that the H10 HA retains a strong preference for avian receptor analogs and negligible binding to human receptor analogs. Crystal structures of H10 HA with avian and human receptor analogs revealed the basis for preferential recognition of avian-like receptors. Furthermore, introduction of mutations into the H10 receptor-binding site (RBS) known to convert other HA subtypes from avian to human receptor specificity failed to switch preference to human receptors. Collectively, these findings suggest that the current H10N8 human isolates are poorly adapted for efficient human-to-human transmission. PMID:25766296

  4. A human-infecting H10N8 influenza virus retains a strong preference for avian-type receptors

    PubMed Central

    Zhu, Xueyong; Yu, Wenli; McBride, Ryan; Paulson, James C.; Wilson, Ian A.

    2015-01-01

    SUMMARY Recent avian-origin H10N8 influenza A viruses that have infected humans pose a potential pandemic threat. Alterations in the viral surface glycoprotein, hemagglutinin (HA), typically allow influenza A viruses to cross the species barrier for adaptation to a new host, but whether H10N8 contains adaptations supporting human infection remains incompletely understood. We investigated whether the H10N8 HA can bind human receptors. Sialoside glycan microarray analysis showed that the H10 HA retains a strong preference for avian receptor analogs and negligible binding to human receptor analogs. Crystal structures of H10 HA with avian and human receptor analogs revealed the basis for preferential recognition of avian-like receptors. Furthermore, introduction of mutations into the H10 receptor-binding site (RBS) known to convert other HA subtypes from avian to human receptor specificity failed to switch the preference to human receptors. Collectively, these findings suggest the current H10N8 human isolates are poorly adapted for efficient human-to-human transmission. PMID:25766296

  5. Oncolytic Activity of Avian Influenza Virus in Human Pancreatic Ductal Adenocarcinoma Cell Lines

    PubMed Central

    Pizzuto, Matteo S.; Silic-Benussi, Micol; Pavone, Silvia; Ciminale, Vincenzo; Capua, Ilaria

    2014-01-01

    ABSTRACT Pancreatic ductal adenocarcinoma (PDA) is the most lethal form of human cancer, with dismal survival rates due to late-stage diagnoses and a lack of efficacious therapies. Building on the observation that avian influenza A viruses (IAVs) have a tropism for the pancreas in vivo, the present study was aimed at testing the efficacy of IAVs as oncolytic agents for killing human PDA cell lines. Receptor characterization confirmed that human PDA cell lines express the alpha-2,3- and the alpha-2,6-linked glycan receptor for avian and human IAVs, respectively. PDA cell lines were sensitive to infection by human and avian IAV isolates, which is consistent with this finding. Growth kinetic experiments showed preferential virus replication in PDA cells over that in a nontransformed pancreatic ductal cell line. Finally, at early time points posttreatment, infection with IAVs caused higher levels of apoptosis in PDA cells than gemcitabine and cisplatin, which are the cornerstone of current therapies for PDA. In the BxPC-3 PDA cell line, apoptosis resulted from the engagement of the intrinsic mitochondrial pathway. Importantly, IAVs did not induce apoptosis in nontransformed pancreatic ductal HPDE6 cells. Using a model based on the growth of a PDA cell line as a xenograft in SCID mice, we also show that a slightly pathogenic avian IAV significantly inhibited tumor growth following intratumoral injection. Taken together, these results are the first to suggest that IAVs may hold promise as future agents of oncolytic virotherapy against pancreatic ductal adenocarcinomas. IMPORTANCE Despite intensive studies aimed at designing new therapeutic approaches, PDA still retains the most dismal prognosis among human cancers. In the present study, we provide the first evidence indicating that avian IAVs of low pathogenicity display a tropism for human PDA cells, resulting in viral RNA replication and a potent induction of apoptosis in vitro and antitumor effects in vivo. These

  6. Avian influenza vaccination and control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) remains an economic threat to commercial poultry throughout the world by negatively impacting animal health and trade. Vaccination with high quality efficacious vaccines that are properly delivered can contribute to the control of avian AI outbreaks when used as part of a compr...

  7. Putative Human and Avian Risk Factors for Avian Influenza Virus Infections in Backyard Poultry in Egypt

    PubMed Central

    Sheta, Basma M.; Fuller, Trevon L.; Larison, Brenda; Njabo, Kevin Y.; Ahmed, Ahmed Samy; Harrigan, Ryan; Chasar, Anthony; Aziz, Soad Abdel; Khidr, Abdel-Aziz A.; Elbokl, Mohamed M.; Habbak, Lotfy Z.; Smith, Thomas B.

    2014-01-01

    Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n=1,084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010–2012. Cloacal and tracheal swabs and serum samples from domestic (n=1242)and wild birds (n=807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n=306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n = 51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F = 15.7, p< 0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F= 29.5, p< 0.0001). PMID:24315038

  8. Putative human and avian risk factors for avian influenza virus infections in backyard poultry in Egypt.

    PubMed

    Sheta, Basma M; Fuller, Trevon L; Larison, Brenda; Njabo, Kevin Y; Ahmed, Ahmed Samy; Harrigan, Ryan; Chasar, Anthony; Abdel Aziz, Soad; Khidr, Abdel-Aziz A; Elbokl, Mohamed M; Habbak, Lotfy Z; Smith, Thomas B

    2014-01-10

    Highly pathogenic influenza A virus subtype H5N1 causes significant poultry mortality in the six countries where it is endemic and can also infect humans. Egypt has reported the third highest number of poultry outbreaks (n=1084) globally. The objective of this cross-sectional study was to identify putative risk factors for H5N1 infections in backyard poultry in 16 villages in Damietta, El Gharbia, Fayoum, and Menofia governorates from 2010-2012. Cloacal and tracheal swabs and serum samples from domestic (n=1242) and wild birds (n=807) were tested for H5N1 via RT-PCR and hemagglutination inhibition, respectively. We measured poultry rearing practices with questionnaires (n=306 households) and contact rates among domestic and wild bird species with scan sampling. Domestic birds (chickens, ducks, and geese, n=51) in three governorates tested positive for H5N1 by PCR or serology. A regression model identified a significant correlation between H5N1 in poultry and the practice of disposing of dead poultry and poultry feces in the garbage (F=15.7, p<0.0001). In addition, contact between domestic and wild birds was more frequent in villages where we detected H5N1 in backyard flocks (F=29.5, p<0.0001). PMID:24315038

  9. Avian influenza and pandemic influenza preparedness in Hong Kong.

    PubMed

    Lam, Ping Yan

    2008-06-01

    Avian influenza A H5N1 continues to be a major threat to global public health as it is a likely candidate for the next influenza pandemic. To protect public health and avert potential disruption to the economy, the Hong Kong Special Administrative Region Government has committed substantial effort in preparedness for avian and pandemic influenza. Public health infrastructures for emerging infectious diseases have been developed to enhance command, control and coordination of emergency response. Strategies against avian and pandemic influenza are formulated to reduce opportunities for human infection, detect pandemic influenza timely, and enhance emergency preparedness and response capacity. Key components of the pandemic response include strengthening disease surveillance systems, updating legislation on infectious disease prevention and control, enhancing traveller health measures, building surge capacity, maintaining adequate pharmaceutical stockpiles, and ensuring business continuity during crisis. Challenges from avian and pandemic influenza are not to be underestimated. Implementing quarantine and social distancing measures to contain or mitigate the spread of pandemic influenza is problematic in a highly urbanised city like Hong Kong as they involved complex operational and ethical issues. Sustaining effective risk communication campaigns during interpandemic times is another challenge. Being a member of the global village, Hong Kong is committed to contributing its share of efforts and collaborating with health authorities internationally in combating our common public health enemy. PMID:18618061

  10. 76 FR 24793 - Highly Pathogenic Avian Influenza

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ... Inspection Service 9 CFR Parts 93, 94, and 95 RIN 0579-AC36 Highly Pathogenic Avian Influenza AGENCY: Animal... products from regions where any subtype of highly pathogenic avian influenza is considered to exist. The... vaccinated for certain types of avian influenza, or that have moved through regions where any subtype...

  11. Sequencing of avian influenza virus genomes following random amplification

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian Influenza (AI) is a significant disease of birds and a threat to humans. Recently, as a result of the emergence of Asian H5N1 viruses capable of zoonotic spread, wild and domestic bird surveillance for Avian Influenza viruses (AIV) has increased worldwide, requiring the development of fast a...

  12. Avian influenza in Indonesia: Observations of disease detection in poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Highly pathogenic avian influenza, subtype H5N1, also known as highly pathogenic notifiable avian influenza (HPNAI), has spread throughout Indonesia since 2003. As of June 2007 there have been a total of 100 documented human cases in Indonesia, 80 of which have been fatal. Although efforts have be...

  13. Poultry food products--a source of avian influenza virus transmission to humans?

    PubMed

    Harder, T C; Buda, S; Hengel, H; Beer, M; Mettenleiter, T C

    2016-02-01

    Global human mobility and intercontinental connectivity, expansion of livestock production and encroachment of wildlife habitats by invasive agricultural land use contribute to shape the complexity of influenza epidemiology. The OneHealth approach integrates these and further elements into considerations to improve disease control and prevention. Food of animal origin for human consumption is another integral aspect; if produced from infected livestock such items may act as vehicles of spread of animal pathogens, and, in case of zoonotic agents, as a potential human health hazard. Notifiable zoonotic avian influenza viruses (AIV) have become entrenched in poultry populations in several Asian and northern African countries since 2003. Highly pathogenic (HP) AIV (e.g. H5N1) cause extensive poultry mortality and severe economic losses. HPAIV and low pathogenic AIV (e.g. H7N9) with zoonotic propensities pose risks for human health. More than 1500 human cases of AIV infection have been reported, mainly from regions with endemically infected poultry. Intense human exposure to AIV-infected poultry, e.g. during rearing, slaughtering or processing of poultry, is a major risk factor for acquiring AIV infection. In contrast, human infections through consumption of AIV-contaminated food have not been substantiated. Heating poultry products according to kitchen standards (core temperatures ≥70°C, ≥10 s) rapidly inactivates AIV infectivity and renders fully cooked products safe. Nevertheless, concerted efforts must ensure that poultry products potentially contaminated with zoonotic AIV do not reach the food chain. Stringent and sustained OneHealth measures are required to better control and eventually eradicate, HPAIV from endemic regions. PMID:26686812

  14. Virus-neutralizing antibody response of mice to consecutive infection with human and avian influenza A viruses.

    PubMed

    Janulíková, J; Stropkovská, A; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

    2015-06-01

    In this work we simulated in a mouse model a naturally occurring situation of humans, who overcame an infection with epidemic strains of influenza A, and were subsequently exposed to avian influenza A viruses (IAV). The antibody response to avian IAV in mice previously infected with human IAV was analyzed. We used two avian IAV (A/Duck/Czechoslovakia/1956 (H4N6) and the attenuated virus rA/Viet Nam/1203-2004 (H5N1)) as well as two human IAV isolates (virus A/Mississippi/1/1985 (H3N2) of medium virulence and A/Puerto Rico/8/1934 (H1N1) of high virulence). Two repeated doses of IAV of H4 or of H5 virus elicited virus-specific neutralizing antibodies in mice. Exposure of animals previously infected with human IAV (of H3 or H1 subtype) to IAV of H4 subtype led to the production of antibodies neutralizing H4 virus in a level comparable with the level of antibodies against the human IAV used for primary infection. In contrast, no measurable levels of virus-neutralizing (VN) antibodies specific to H5 virus were detected in mice infected with H5 virus following a previous infection with human IAV. In both cases the secondary infection with avian IAV led to a significant increase of the titer of VN antibodies specific to the corresponding human virus used for primary infection. Moreover, cross-reactive HA2-specific antibodies were also induced by sequential infection. By virtue of these results we suggest that the differences in the ability of avian IAV to induce specific antibodies inhibiting virus replication after previous infection of mice with human viruses can have an impact on the interspecies transmission and spread of avian IAV in the human population. PMID:26104333

  15. Novel Avian Influenza A (H7N9) Virus Induces Impaired Interferon Responses in Human Dendritic Cells

    PubMed Central

    Arilahti, Veera; Mäkelä, Sanna M.; Tynell, Janne; Julkunen, Ilkka; Österlund, Pamela

    2014-01-01

    In March 2013 a new avian influenza A(H7N9) virus emerged in China and infected humans with a case fatality rate of over 30%. Like the highly pathogenic H5N1 virus, H7N9 virus is causing severe respiratory distress syndrome in most patients. Based on genetic analysis this avian influenza A virus shows to some extent adaptation to mammalian host. In the present study, we analyzed the activation of innate immune responses by this novel H7N9 influenza A virus and compared these responses to those induced by the avian H5N1 and seasonal H3N2 viruses in human monocyte-derived dendritic cells (moDCs). We observed that in H7N9 virus-infected cells, interferon (IFN) responses were weak although the virus replicated as well as the H5N1 and H3N2 viruses in moDCs. H7N9 virus-induced expression of pro-inflammatory cytokines remained at a significantly lower level as compared to H5N1 virus-induced “cytokine storm” seen in human moDCs. However, the H7N9 virus was extremely sensitive to the antiviral effects of IFN-α and IFN-β in pretreated cells. Our data indicates that different highly pathogenic avian viruses may show considerable differences in their ability to induce host antiviral responses in human primary cell models such as moDCs. The unexpected appearance of the novel H7N9 virus clearly emphasizes the importance of the global influenza surveillance system. It is, however, equally important to systematically characterize in normal human cells the replication capacity of the new viruses and their ability to induce and respond to natural antiviral substances such as IFNs. PMID:24804732

  16. Characteristics of human infection with avian influenza viruses and development of new antiviral agents

    PubMed Central

    Liu, Qiang; Liu, Dong-ying; Yang, Zhan-qiu

    2013-01-01

    Since 1997, several epizootic avian influenza viruses (AIVs) have been transmitted to humans, causing diseases and even deaths. The recent emergence of severe human infections with AIV (H7N9) in China has raised concerns about efficient interpersonal viral transmission, polygenic traits in viral pathogenicity and the management of newly emerging strains. The symptoms associated with viral infection are different in various AI strains: H5N1 and newly emerged H7N9 induce severe pneumonia and related complications in patients, while some H7 and H9 subtypes cause only conjunctivitis or mild respiratory symptoms. The virulence and tissue tropism of viruses as well as the host responses contribute to the pathogenesis of human AIV infection. Several preventive and therapeutic approaches have been proposed to combat AIV infection, including antiviral drugs such as M2 inhibitors, neuraminidase inhibitors, RNA polymerase inhibitors, attachment inhibitors and signal-transduction inhibitors etc. In this article, we summarize the recent progress in researches on the epidemiology, clinical features, pathogenicity determinants, and available or potential antivirals of AIV. PMID:24096642

  17. Avian influenza A H5N1 virus: a continuous threat to humans

    PubMed Central

    To, Kelvin KW; Ng, Kenneth HL; Que, Tak-Lun; Chan, Jacky MC; Tsang, Kay-Yan; Tsang, Alan KL; Chen, Honglin; Yuen, Kwok-Yung

    2012-01-01

    We report the first case of severe pneumonia due to co-infection with the emerging avian influenza A (H5N1) virus subclade 2.3.2.1 and Mycoplasma pneumoniae. The patient was a returning traveller who had visited a poultry market in South China. We then review the epidemiology, virology, interspecies barrier limiting poultry-to-human transmission, clinical manifestation, laboratory diagnosis, treatment and control measures of H5N1 clades that can be transmitted to humans. The recent controversy regarding the experiments involving aerosol transmission of recombinant H5N1 virus between ferrets is discussed. We also review the relative contribution of the poor response to antiviral treatment and the virus-induced hyperinflammatory damage to the pathogenesis and the high mortality of this infection. The factors related to the host, virus or medical intervention leading to the difference in disease mortality of different countries remain unknown. Because most developing countries have difficulty in instituting effective biosecurity measures, poultry vaccination becomes an important control measure. The rapid evolution of the virus would adversely affect the efficacy of poultry vaccination unless a correctly matched vaccine was chosen, manufactured and administered in a timely manner. Vigilant surveillance must continue to allow better preparedness for another poultry or human pandemic due to new viral mutants. PMID:26038430

  18. Effects of closing and reopening live poultry markets on the epidemic of human infection with avian influenza A virus

    PubMed Central

    Lu, Jian; Liu, Wendong; Xia, Rui; Dai, Qigang; Bao, Changjun; Tang, Fenyang; Zhu, yefei; Wang, Qiao

    2016-01-01

    Abstract Live poultry markets (LPMs) are crucial places for human infection of influenza A (H7N9 virus). In Yangtze River Delta, LPMs were closed after the outbreak of human infection with avian influenza A (H7N9) virus, and then reopened when no case was found. Our purpose was to quantify the effect of LPMs’ operations in this region on the transmission of influenza A (H7N9) virus. We obtained information about dates of symptom onset and locations for all human influenza A (H7N9) cases reported from Shanghai, Jiangsu and Zhejiang provinces by May 31, 2014, and acquired dates of closures and reopening of LPMs from official media. A two-phase Bayesian model was fitted by Markov Chain Monte Carlo methods to process the spatial and temporal influence of human cases. A total of 235 cases of influenza A (H7N9) were confirmed in Shanghai, Jiangsu and Zhejiang by May 31, 2014. Using these data, our analysis showed that, after LPM closures, the influenza A (H7N9) outbreak disappeared within two weeks in Shanghai, one week in Jiangsu, and one week in Zhejiang, respectively. Local authorities reopened LPMs when there was no outbreak of influenza A (H7N9), which did not lead to reemergence of human influenza A (H7N9). LPM closures were effective in controlling the H7N9 outbreak. Reopening of LPM in summer did not increase the risk of human infection with H7N9. Our findings showed that LPMs should be closed immediately in areas where the H7N9 virus is confirmed in LPM. When there is no outbreak of H7N9 virus, LPMs can be reopened to satisfy the Chinese traditional culture of buying live poultry. In the long term, local authorities should take a cautious attitude in permanent LPM closure.

  19. Avian influenza virus RNA extraction

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The efficient extraction and purification of viral RNA is critical for down-stream molecular applications whether it is the sensitive and specific detection of virus in clinical samples, virus gene cloning and expression, or quantification of avian influenza (AI) virus by molecular methods from expe...

  20. Avian Influenza: Our current understanding

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) has become one of the most important diseases of the poultry industry around the world. The virus has a broad host range in birds and mammals, although the natural reservoir is considered to be in wild birds where it typically causes an asymptomatic to mild infection. T...

  1. Influenza vaccines for avian species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Beginning in Southeast Asia, in 2003, a multi-national epizootic outbreak of H5N1 highly pathogenic avian influenza (HPAI) was identified in commercial poultry and wild bird species. This lineage, originally identified in Southern China in 1996 and then Hong Kong in 1997, caused severe morbidity an...

  2. Prevalence and control of H7 avian influenza viruses in birds and humans.

    PubMed

    Abdelwhab, E M; Veits, J; Mettenleiter, T C

    2014-05-01

    The H7 subtype HA gene has been found in combination with all nine NA subtype genes. Most exhibit low pathogenicity and only rarely high pathogenicity in poultry (and humans). During the past few years infections of poultry and humans with H7 subtypes have increased markedly. This review summarizes the emergence of avian influenza virus H7 subtypes in birds and humans, and the possibilities of its control in poultry. All H7Nx combinations were reported from wild birds, the natural reservoir of the virus. Geographically, the most prevalent subtype is H7N7, which is endemic in wild birds in Europe and was frequently reported in domestic poultry, whereas subtype H7N3 is mostly isolated from the Americas. In humans, mild to fatal infections were caused by subtypes H7N2, H7N3, H7N7 and H7N9. While infections of humans have been associated mostly with exposure to domestic poultry, infections of poultry have been linked to wild birds or live-bird markets. Generally, depopulation of infected poultry was the main control tool; however, inactivated vaccines were also used. In contrast to recent cases caused by subtype H7N9, human infections were usually self-limiting and rarely required antiviral medication. Close genetic and antigenic relatedness of H7 viruses of different origins may be helpful in development of universal vaccines and diagnostics for both animals and humans. Due to the wide spread of H7 viruses and their zoonotic importance more research is required to better understand the epidemiology, pathobiology and virulence determinants of these viruses and to develop improved control tools. PMID:24423384

  3. A brief introduction to avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is caused by a type A influenza virus isolated from and adapted to an avian host. This chapter covers the basic physicochemical aspects of AIV including; virus family and properties, subtype classification; basic molecular biology and genetics. The avian host range and ecology...

  4. 77 FR 34783 - Highly Pathogenic Avian Influenza

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-12

    ... avian influenza (HPAI). On January 24, 2011, we published in the Federal Register (76 FR 4046-4056... Avian Influenza AGENCY: Animal and Plant Health Inspection Service, USDA. ACTION: Interim rule... importation of bird and poultry products from regions where any subtype of highly pathogenic avian...

  5. Pandemic Threat Posed by Avian Influenza A Viruses

    PubMed Central

    Horimoto, Taisuke; Kawaoka, Yoshihiro

    2001-01-01

    Influenza pandemics, defined as global outbreaks of the disease due to viruses with new antigenic subtypes, have exacted high death tolls from human populations. The last two pandemics were caused by hybrid viruses, or reassortants, that harbored a combination of avian and human viral genes. Avian influenza viruses are therefore key contributors to the emergence of human influenza pandemics. In 1997, an H5N1 influenza virus was directly transmitted from birds in live poultry markets in Hong Kong to humans. Eighteen people were infected in this outbreak, six of whom died. This avian virus exhibited high virulence in both avian and mammalian species, causing systemic infection in both chickens and mice. Subsequently, another avian virus with the H9N2 subtype was directly transmitted from birds to humans in Hong Kong. Interestingly, the genes encoding the internal proteins of the H9N2 virus are genetically highly related to those of the H5N1 virus, suggesting a unique property of these gene products. The identification of avian viruses in humans underscores the potential of these and similar strains to produce devastating influenza outbreaks in major population centers. Although highly pathogenic avian influenza viruses had been identified before the 1997 outbreak in Hong Kong, their devastating effects had been confined to poultry. With the Hong Kong outbreak, it became clear that the virulence potential of these viruses extended to humans. PMID:11148006

  6. DIVA vaccination strategies for avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccination for both low pathogenic and highly pathogenic avian influenza is commonly used for countries that have been endemic for avian influenza influenza virus, but stamping out policies are common for countries that are normally free of the disease. Stamping out policies of euthanizing infecte...

  7. Environmental connections of novel avian-origin H7N9 influenza virus infection and virus adaptation to the human.

    PubMed

    Li, Jun; Yu, Xinfen; Pu, Xiaoying; Xie, Li; Sun, Yongxiang; Xiao, Haixia; Wang, Fenjuan; Din, Hua; Wu, Ying; Liu, Di; Zhao, Guoqiu; Liu, Jun; Pan, Jingcao

    2013-06-01

    A novel H7N9 influenza A virus has been discovered as the causative identity of the emerging acute respiratory infection cases in Shanghai, China. This virus has also been identified in cases of infection in the neighboring area Hangzhou City in Zhejiang Province. In this study, epidemiologic, clinical, and virological data from three patients in Hangzhou who were confirmed to be infected by the novel H7N9 influenza A virus were collected and analyzed. Human respiratory specimens and chicken feces from a contacted free market were tested for influenza virus by real-time reverse transcription PCR (RT-PCR) and sequencing. The clinical features of the three cases were similar featured with high fever and severe respiratory symptoms; however, only one of the patients died. A certain degree of diversity was observed among the three Hangzhou viruses sequenced from human samples compared with other reported H7N9 influenza A viruses. The sequences of the novel avian-origin H7N9 influenza viruses from Hangzhou City contained important amino acid substitutions related to human adaptation. One of the Hangzhou viruses had gained a novel amino acid substitution (Q226I) in the receptor binding region of hemagglutinin. More importantly, the virus sequenced from the chicken feces had a 627E substitution in the PB2 protein instead of the mammalian-adapted 627K substitution that was found in the PB2 proteins from the Hangzhou viruses from the three patients. Therefore, the newly-emerging H7N9 virus might be under adaptation pressure that will help it "jump" from avian to human hosts. The significance of these substitutions needs further exploration, with both laboratory experiments and extensive field surveillance. PMID:23657795

  8. Avian-to-human transmission of the PB1 gene of influenza A viruses in the 1957 and 1968 pandemics.

    PubMed Central

    Kawaoka, Y; Krauss, S; Webster, R G

    1989-01-01

    We determined the origin and evolutionary pathways of the PB1 genes of influenza A viruses responsible for the 1957 and 1968 human pandemics and obtained information on the variable or conserved region of the PB1 protein. The evolutionary tree constructed from nucleotide sequences suggested the following: (i) the PB1 gene of the 1957 human pandemic strain, A/Singapore/1/57 (H2N2), was probably introduced from avian species and was maintained in humans until 1968; (ii) in the 1968 pandemic strain, A/NT/60/68 (H3N2), the PB1 gene was not derived from the previously circulating virus in humans but probably from another avian virus; and (iii) a current human H3N2 virus inherited the PB1 gene from an A/NT/60/68-like virus. Nucleotide sequence analysis also showed that the avian PB1 gene was introduced into pigs. Hence, transmission of the PB1 gene from avian to mammalian species is a relatively frequent event. Comparative analysis of deduced amino acid sequences disclosed highly conserved regions in PB1 proteins, which may be key structures required for PB1 activities. PMID:2795713

  9. An overview of the characteristics of the novel avian influenza A H7N9 virus in humans

    PubMed Central

    Tan, Kei-Xian; Jacob, Sabrina A.; Chan, Kok-Gan; Lee, Learn-Han

    2015-01-01

    The novel avian influenza A H7N9 virus which caused the first human infection in Shanghai, China; was reported on the 31st of March 2013 before spreading rapidly to other Chinese provinces and municipal cities. This is the first time the low pathogenic avian influenza A virus has caused human infections and deaths; with cases of severe respiratory disease with pneumonia being reported. There were 440 confirmed cases with 122 fatalities by 16 May 2014; with a fatality risk of ∼28%. The median age of patients was 61 years with a male-to-female ratio of 2.4:1. The main source of infection was identified as exposure to poultry and there is so far no definitive evidence of sustained person-to-person transmission. The neuraminidase inhibitors, namely oseltamivir, zanamivir, and peramivir; have shown good efficacy in the management of the novel H7N9 virus. Treatment is recommended for all hospitalized patients, and for confirmed and probable outpatient cases; and should ideally be initiated within 48 h of the onset of illness for the best outcome. Phylogenetic analysis found that the novel H7N9 virus is avian in origin and evolved from multiple reassortments of at least four origins. Indeed the novel H7N9 virus acquired human adaptation via mutations in its eight RNA gene segments. Enhanced surveillance and effective global control are essential to prevent pandemic outbreaks of the novel H7N9 virus. PMID:25798131

  10. Emergence in China of human disease due to avian influenza A(H10N8)--cause for concern?

    PubMed

    To, Kelvin K W; Tsang, Alan K L; Chan, Jasper F W; Cheng, Vincent C C; Chen, Honglin; Yuen, Kwok-Yung

    2014-03-01

    In December 2013, China reported the first human case of avian influenza A(H10N8). A 73-year-old female with chronic diseases who had visited a live poultry market succumbed with community-acquired pneumonia. While human infections with avian influenza viruses are usually associated with subtypes prevalent in poultries, A(H10N8) isolates were mostly found in migratory birds and only recently in poultries. Although not possible to predict whether this single intrusion by A(H10N8) is an accident or the start of another epidemic like the preceding A(H7N9) and A(H5N1), several features suggest that A(H10N8) is a potential threat to humans. Recombinant H10 could attach to human respiratory epithelium, and A(H10N4) virus could cause severe infections in minks and chickens. A(H10N8) viruses contain genetic markers for mammalian adaptation and virulence in the haemagglutinin (A135T, S138A[H3 numbering]), M1(N30D, T215A), NS1(P42S) and PB2(E627K) protein. Studies on this human A(H10N8) isolate will reveal its adaptability to humans. Clinicians should alert the laboratory to test for A(H5,6,7,9,10) viruses in patients with epidemiological exposure in endemic geographical areas especially when human influenza A(H1,3) and B are negative. Vigilant virological and serological surveillance for A(H10N8) in human, poultry and wild bird is important for following the trajectory of this emerging influenza virus. PMID:24406432

  11. Avian influenza: the Canadian experience.

    PubMed

    Pasick, J; Berhane, Y; Hooper-McGrevy, K

    2009-04-01

    Reports of sporadic avian influenza outbreaks involving domestic poultry date back to the 1960s. With the exception of A/turkey/Ontario/7732/1966 (H5N9), which was isolated from a turkey breeding establishment, all viruses characterised prior to 2004 fit the criteria of low pathogenic avian influenza (LPAI). Only in retrospect was A/turkey/Ontario/7732/1966 shown to meet the criteria of a highly pathogenic avian influenza (HPAI). In 2004, Canada reported its first case of HPAI to the World Organisation for Animal Health (OIE). The outbreak, which began in a broiler breeder farm in the Fraser Valley of British Columbia, involved an H7N3 LPAI virus which underwent a sudden virulence shift to HPAI. More than 17 million birds were culled and CAN$380 million in gross economic costs incurred before the outbreak was eventually brought under control. In its aftermath a number of changes were implemented to mitigate the impact of any future HPAI outbreaks. These changes involved various aspects of avian influenza detection and control, including self-quarantine, biosecurity, surveillance, and laboratory testing. In 2005, a national surveillance programme for influenza A viruses in wild birds was initiated. Results of this survey provided evidence for wild birds as the likely source of an H5N2 LPAI outbreak that occurred in domestic ducks in the Fraser Valley in the autumn of 2005. Wild birds were once again implicated in an H7N3 HPAI outbreak involving a broiler breeder operation in Saskatchewan in 2007. Fortunately, both of these outbreaks were limited in extent, a consequence of some of the changes implemented in response to the 2004 British Columbia outbreak. PMID:19618638

  12. Avian Influenza in Birds

    MedlinePlus

    ... and even kill certain domesticated bird species including chickens, ducks, and turkeys. Infected birds can shed avian ... virus’ ability to cause disease and mortality in chickens in a laboratory setting [2.5 MB, 64 ...

  13. Avian and pandemic human influenza policy in South-East Asia: the interface between economic and public health imperatives.

    PubMed

    Pongcharoensuk, Petcharat; Adisasmito, Wiku; Sat, Le Minh; Silkavute, Pornpit; Muchlisoh, Lilis; Cong Hoat, Pham; Coker, Richard

    2012-08-01

    The aim of this study was to analyse the contemporary policies regarding avian and human pandemic influenza control in three South-East Asia countries: Thailand, Indonesia and Vietnam. An analysis of poultry vaccination policy was used to explore the broader policy of influenza A H5N1 control in the region. The policy of antiviral stockpiling with oseltamivir, a scarce regional resource, was used to explore human pandemic influenza preparedness policy. Several policy analysis theories were applied to analyse the debate on the use of vaccination for poultry and stockpiling of antiviral drugs in each country case study. We conducted a comparative analysis across emergent themes. The study found that whilst Indonesia and Vietnam introduced poultry vaccination programmes, Thailand rejected this policy approach. By contrast, all three countries adopted similar strategic policies for antiviral stockpiling in preparation. In relation to highly pathogenic avian influenza, economic imperatives are of critical importance. Whilst Thailand's poultry industry is large and principally an export economy, Vietnam's and Indonesia's are for domestic consumption. The introduction of a poultry vaccination policy in Thailand would have threatened its potential to trade and had a major impact on its economy. Powerful domestic stakeholders in Vietnam and Indonesia, by contrast, were concerned less about international trade and more about maintaining a healthy domestic poultry population. Evidence on vaccination was drawn upon differently depending upon strategic economic positioning either to support or oppose the policy. With influenza A H5N1 endemic in some countries of the region, these policy differences raise questions around regional coherence of policies and the pursuit of an agreed overarching goal, be that eradication or mitigation. Moreover, whilst economic imperatives have been critically important in guiding policy formulation in the agriculture sector, questions arise

  14. Single assay for simultaneous detection and differential identification of human and avian influenza virus types, subtypes, and emergent variants.

    PubMed

    Metzgar, David; Myers, Christopher A; Russell, Kevin L; Faix, Dennis; Blair, Patrick J; Brown, Jason; Vo, Scott; Swayne, David E; Thomas, Colleen; Stenger, David A; Lin, Baochuan; Malanoski, Anthony P; Wang, Zheng; Blaney, Kate M; Long, Nina C; Schnur, Joel M; Saad, Magdi D; Borsuk, Lisa A; Lichanska, Agnieszka M; Lorence, Matthew C; Weslowski, Brian; Schafer, Klaus O; Tibbetts, Clark

    2010-01-01

    For more than four decades the cause of most type A influenza virus infections of humans has been attributed to only two viral subtypes, A/H1N1 or A/H3N2. In contrast, avian and other vertebrate species are a reservoir of type A influenza virus genome diversity, hosting strains representing at least 120 of 144 combinations of 16 viral hemagglutinin and 9 viral neuraminidase subtypes. Viral genome segment reassortments and mutations emerging within this reservoir may spawn new influenza virus strains as imminent epidemic or pandemic threats to human health and poultry production. Traditional methods to detect and differentiate influenza virus subtypes are either time-consuming and labor-intensive (culture-based) or remarkably insensitive (antibody-based). Molecular diagnostic assays based upon reverse transcriptase-polymerase chain reaction (RT-PCR) have short assay cycle time, and high analytical sensitivity and specificity. However, none of these diagnostic tests determine viral gene nucleotide sequences to distinguish strains and variants of a detected pathogen from one specimen to the next. Decision-quality, strain- and variant-specific pathogen gene sequence information may be critical for public health, infection control, surveillance, epidemiology, or medical/veterinary treatment planning. The Resequencing Pathogen Microarray (RPM-Flu) is a robust, highly multiplexed and target gene sequencing-based alternative to both traditional culture- or biomarker-based diagnostic tests. RPM-Flu is a single, simultaneous differential diagnostic assay for all subtype combinations of type A influenza viruses and for 30 other viral and bacterial pathogens that may cause influenza-like illness. These other pathogen targets of RPM-Flu may co-infect and compound the morbidity and/or mortality of patients with influenza. The informative specificity of a single RPM-Flu test represents specimen-specific viral gene sequences as determinants of virus type, A/HN subtype, virulence

  15. Human infection with an avian influenza A (H9N2) virus in the middle region of China.

    PubMed

    Huang, Yiwei; Li, Xiaodan; Zhang, Hong; Chen, Bozhong; Jiang, Yonglin; Yang, Lei; Zhu, Wenfei; Hu, Shixiong; Zhou, Siyu; Tang, Yunli; Xiang, Xingyu; Li, Fangcai; Li, Wenchao; Gao, Lidong

    2015-10-01

    During the epidemic period of the novel H7N9 viruses, an influenza A (H9N2) virus was isolated from a 7-year-old boy with influenza-like illness in Yongzhou city of Hunan province in November 2013. To identify the possible source of infection, environmental specimens collected from local live poultry markets epidemiologically linked to the human case in Yongzhou city were tested for influenza type A and its subtypes H5, H7, and H9 using real-time RT-PCR methods as well as virus isolation, and four other H9N2 viruses were isolated. The real-time RT-PCR results showed that the environment was highly contaminated with avian influenza H9 subtype viruses (18.0%). Sequencing analyses revealed that the virus isolated from the patient, which was highly similar (98.5-99.8%) to one of isolates from environment in complete genome sequences, was of avian origin. Based on phylogenetic and antigenic analyses, it belonged to genotype S and Y280 lineage. In addition, the virus exhibited high homology (95.7-99.5%) of all six internal gene lineages with the novel H7N9 and H10N8 viruses which caused epidemic and endemic in China. Meanwhile, it carried several mammalian adapted molecular residues including Q226L in HA protein, L13P in PB1 protein, K356R, S409N in PA protein, V15I in M1 protein, I28V, L55F in M2 protein, and E227K in NS protein. These findings reinforce the significance of continuous surveillance of H9N2 influenza viruses. PMID:25965534

  16. Poultry farms as a source of avian influenza A (H7N9) virus reassortment and human infection

    PubMed Central

    Wu, Donglin; Zou, Shumei; Bai, Tian; Li, Jing; Zhao, Xiang; Yang, Lei; Liu, Hongmin; Li, Xiaodan; Yang, Xianda; Xin, Li; Xu, Shuang; Zou, Xiaohui; Li, Xiyan; Wang, Ao; Guo, Junfeng; Sun, Bingxin; Huang, Weijuan; Zhang, Ye; Li, Xiang; Gao, Rongbao; Shen, Bo; Chen, Tao; Dong, Jie; Wei, Hejiang; Wang, Shiwen; Li, Qun; Li, Dexin; Wu, Guizhen; Feng, Zijian; Gao, George F.; Wang, Yu; Wang, Dayan; Fan, Ming; Shu, Yuelong

    2015-01-01

    Live poultry markets are a source of human infection with avian influenza A (H7N9) virus. On February 21, 2014, a poultry farmer infected with H7N9 virus was identified in Jilin, China, and H7N9 and H9N2 viruses were isolated from the patient's farm. Reassortment between these subtype viruses generated five genotypes, one of which caused the human infection. The date of H7N9 virus introduction to the farm is estimated to be between August 21, 2013 (95% confidence interval [CI] June 6, 2013-October 6, 2013) and September 25, 2013 (95% CI May 28, 2013-January 4, 2014), suggesting that the most likely source of virus introduction was the first batch of poultry purchased in August 2013. The reassortment event that led to the human virus may have occurred between January 2, 2014 (95% CI November 8, 2013-February 12, 2014) and February 12, 2014 (95% CI January 19, 2014-February 18, 2014). Our findings demonstrate that poultry farms could be a source of reassortment between H7N9 virus and H9N2 virus as well as human infection, which emphasizes the importance to public health of active avian influenza surveillance at poultry farms. PMID:25591105

  17. Biology and transmission of avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The natural host and reservoir for avian influenza is in wild birds where the viral infection is typically asymptomatic. The virus primarily replicates in the enteric tract and transmission is thought to be primarily by fecal-oral transmission. Avian influenza can infect a broad host range, but fo...

  18. Avian influenza diagnostics and surveillance methods

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The clinical presentation of avian influenza (AI) varies by virus strain and host species. The clinical disease and lesions the virus produces in poultry are not pathognomonic for avian influenza; therefore, diagnosis of AI virus (AIV) infection requires a laboratory test. Detection of AIV infecti...

  19. Avian influenza biology and disease transmission

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The natural host and reservoir for avian influenza is in wild birds where the viral infection is typically asymptomatic. The virus primarily replicates in the enteric tract and transmission is thought to be primarily by fecal oral transmission. Avian influenza can infect a broad host range, but fo...

  20. Avian influenza: preparedness and response strategies

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus is naturally found in wild birds, primarily waterfowl, but the virus may also be found in poultry. In the United States we have a strong passive and active surveillance program for avian influenza in poultry. This includes serologic testing on most flocks that go through the ...

  1. 76 FR 4046 - Highly Pathogenic Avian Influenza

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-24

    ...We are amending the regulations concerning the importation of animals and animal products to prohibit or restrict the importation of bird and poultry products from regions where any subtype of highly pathogenic avian influenza is considered to exist. We are also adding restrictions concerning importation of live poultry and birds that have been vaccinated for certain types of avian influenza,......

  2. The global nature of avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus is a global virus which knows no geographic boundaries, has no political agenda, and can infect poultry irrespective of their agricultural or anthropocentric production systems. Avian influenza viruses or evidence of their infection have been detected in poultry and wild birds...

  3. A brief introduction to avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) causes a disease of high economic importance for poultry production worldwide. The earliest recorded cases of probable high pathogenicity AIV in poultry were reported in Italy in the 1870’s and avian influenza been recognized in domestic poultry through the modern era of ...

  4. Measurement of antibodies to avian influenza virus A(H7N7) in humans by hemagglutination inhibition test.

    PubMed

    Meijer, Adam; Bosman, Arnold; van de Kamp, Esther E H M; Wilbrink, Berry; Du Ry van Beest Holle, Mirna; Koopmans, Marion

    2006-03-01

    During the epizootic of highly pathogenic avian influenza A(H7N7) in 2003 in The Netherlands, RT-PCR and culture confirmed infection was detected in 89 persons who were ill. A modified hemagglutination inhibition (HI) test using horse erythrocytes and 2 hemagglutinating units of virus was applied to assess retrospectively the extent of human (subclinical) infection. Validation of the HI-test with sera from 34 RT-PCR and culture confirmed A(H7) infected persons and sera from 100 persons from a human influenza vaccine trial in autumn 2002 showed that this HI-test had a sensitivity of 85% and a specificity of 100% when using a cut-off titer of > or =10. Using this cut-off value, A(H7) specific antibodies were detected in 49% of 508 persons exposed to poultry and in 64% of 63 persons exposed to A(H7) infected persons. Correlation of seropositivity with the occurrence of eye symptoms in exposed persons who had not received antiviral prophylaxis and of reduced seropositivity with taking antiviral prophylaxis provided further evidence that the A(H7) HI antibody titers were real. In conclusion, by applying an HI-test using horse erythrocytes human antibodies against the avian A(H7N7) virus were detected with high sensitivity and specificity in an unexpectedly high proportion of exposed persons. PMID:16271401

  5. Human infection with a highly pathogenic avian influenza A (H5N6) virus in Yunnan province, China.

    PubMed

    Xu, Wen; Li, Hong; Jiang, Li

    2016-01-01

    Highly pathogenic avian influenza A H5N6 virus has caused four human infections in China. This study reports the preliminary findings of the first known human case of H5N6 in Yunnan province. The patient initially developed symptoms of sore throat and coughing on 27 January 2015. The disease rapidly progressed to severe pneumonia, multiple organ dysfunctions and acute respiratory distress syndrome and the patient died on 6 February. Virological analysis determined that the virus belonged to H5 clade 2.3.4.4 and it has obtained partial ability for mammalian adaptation and amantadine resistance. Environmental investigation found H5 in 63% of the samples including poultry faeces, tissues, cage surface swabs and sewage from local live poultry markets by real-time RT-PCR. These findings suggest that the expanding and enhancing of surveillance in both avian and humans are necessary to monitor the evolution of H5 influenza virus and to facilitate early detection of suspected cases. PMID:27030920

  6. Avian influenza: Public health and food safety concerns

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian Influenza (AI) is an asymptomatic infection or disease caused by Influenza virus A. AI viruses are species specific and rarely crosses the species barrier. However subtypes H5, H7 and H9 have caused sporadic infections in humans mostly as a result of direct contact with infected birds. H5N1 hi...

  7. Evidence of previous avian influenza infection among US turkey workers.

    PubMed

    Kayali, G; Ortiz, E J; Chorazy, M L; Gray, G C

    2010-06-01

    The threat of an influenza pandemic is looming, with new cases of sporadic avian influenza infections in man frequently reported. Exposure to diseased poultry is a leading risk factor for these infections. In this study, we used logistic regression to investigate serological evidence of previous infection with avian influenza subtypes H4, H5, H6, H7, H8, H9, H10, and H11 among 95 adults occupationally exposed to turkeys in the US Midwest and 82 unexposed controls. Our results indicate that farmers practising backyard, organic or free-ranging turkey production methods are at an increased risk of infection with avian influenza. Among these farmers, the adjusted odds ratios (ORs) for elevated microneutralization assay titres against avian H4, H5, H6, H9, and H10 influenza strains ranged between 3.9 (95% CI 1.2-12.8) and 15.3 (95% CI 2.0-115.2) when compared to non-exposed controls. The measured ORs were adjusted for antibody titres against human influenza viruses and other exposure variables. These data suggest that sometime in their lives, the workers had been exposed to low pathogenicity avian influenza viruses. These findings support calls for inclusion of agricultural workers in priority groups in pandemic influenza preparedness efforts. These data further support increasing surveillance and other preparedness efforts to include not only confinement poultry facilities, but more importantly, also small scale farms. PMID:19486492

  8. Ambient Influenza and Avian Influenza Virus during Dust Storm Days and Background Days

    PubMed Central

    Chen, Pei-Shih; Tsai, Feng Ta; Lin, Chien Kun; Yang, Chun-Yuh; Chan, Chang-Chuan; Young, Chea-Yuan; Lee, Chien-Hung

    2010-01-01

    Background The spread of influenza and highly pathogenic avian influenza (H5N1) presents a significant threat to human health. Avian influenza outbreaks in downwind areas of Asian dust storms (ADS) suggest that viruses might be transported by dust storms. Objectives We developed a technique to measure ambient influenza and avian influenza viruses. We then used this technique to measure concentrations of these viruses on ADS days and background days, and to assess the relationships between ambient influenza and avian influenza viruses, and air pollutants. Methods A high-volume air sampler was used in parallel with a filter cassette to evaluate spiked samples and unspiked samples. Then, air samples were monitored during ADS seasons using a filter cassette coupled with a real-time quantitative polymerase chain reaction (qPCR) assay. Air samples were monitored during ADS season (1 January to 31 May 2006). Results We successfully quantified ambient influenza virus using the filtration/real-time qPCR method during ADS days and background days. To our knowledge, this is the first report describing the concentration of influenza virus in ambient air. In both the spiked and unspiked samples, the concentration of influenza virus sampled using the filter cassette was higher than that using the high-volume sampler. The concentration of ambient influenza A virus was significantly higher during the ADS days than during the background days. Conclusions Our data imply the possibility of long-range transport of influenza virus. PMID:20435545

  9. Avian influenza: Current world situation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The human pandemic H1N1 (pH1N1) virus had its origin with animal influenza viruses, likely through a reassortment event between a North American swine influenza virus and another unidentified virus. The first turkey flock to be diagnosed with pH1N1 occurred in Chile, in August 2009. The flock suff...

  10. Modelling the species jump: towards assessing the risk of human infection from novel avian influenzas

    PubMed Central

    Hill, A. A.; Dewé, T.; Kosmider, R.; Von Dobschuetz, S.; Munoz, O.; Hanna, A.; Fusaro, A.; De Nardi, M.; Howard, W.; Stevens, K.; Kelly, L.; Havelaar, A.; Stärk, K.

    2015-01-01

    The scientific understanding of the driving factors behind zoonotic and pandemic influenzas is hampered by complex interactions between viruses, animal hosts and humans. This complexity makes identifying influenza viruses of high zoonotic or pandemic risk, before they emerge from animal populations, extremely difficult and uncertain. As a first step towards assessing zoonotic risk of influenza, we demonstrate a risk assessment framework to assess the relative likelihood of influenza A viruses, circulating in animal populations, making the species jump into humans. The intention is that such a risk assessment framework could assist decision-makers to compare multiple influenza viruses for zoonotic potential and hence to develop appropriate strain-specific control measures. It also provides a first step towards showing proof of principle for an eventual pandemic risk model. We show that the spatial and temporal epidemiology is as important in assessing the risk of an influenza A species jump as understanding the innate molecular capability of the virus. We also demonstrate data deficiencies that need to be addressed in order to consistently combine both epidemiological and molecular virology data into a risk assessment framework. PMID:26473042

  11. Modelling the species jump: towards assessing the risk of human infection from novel avian influenzas.

    PubMed

    Hill, A A; Dewé, T; Kosmider, R; Von Dobschuetz, S; Munoz, O; Hanna, A; Fusaro, A; De Nardi, M; Howard, W; Stevens, K; Kelly, L; Havelaar, A; Stärk, K

    2015-09-01

    The scientific understanding of the driving factors behind zoonotic and pandemic influenzas is hampered by complex interactions between viruses, animal hosts and humans. This complexity makes identifying influenza viruses of high zoonotic or pandemic risk, before they emerge from animal populations, extremely difficult and uncertain. As a first step towards assessing zoonotic risk of influenza, we demonstrate a risk assessment framework to assess the relative likelihood of influenza A viruses, circulating in animal populations, making the species jump into humans. The intention is that such a risk assessment framework could assist decision-makers to compare multiple influenza viruses for zoonotic potential and hence to develop appropriate strain-specific control measures. It also provides a first step towards showing proof of principle for an eventual pandemic risk model. We show that the spatial and temporal epidemiology is as important in assessing the risk of an influenza A species jump as understanding the innate molecular capability of the virus. We also demonstrate data deficiencies that need to be addressed in order to consistently combine both epidemiological and molecular virology data into a risk assessment framework. PMID:26473042

  12. Global Dynamics of Avian Influenza Epidemic Models with Psychological Effect

    PubMed Central

    Liu, Sanhong; Pang, Liuyong; Ruan, Shigui

    2015-01-01

    Cross-sectional surveys conducted in Thailand and China after the outbreaks of the avian influenza A H5N1 and H7N9 viruses show a high degree of awareness of human avian influenza in both urban and rural populations, a higher level of proper hygienic practice among urban residents, and in particular a dramatically reduced number of visits to live markets in urban population after the influenza A H7N9 outbreak in China in 2013. In this paper, taking into account the psychological effect toward avian influenza in the human population, a bird-to-human transmission model in which the avian population exhibits saturation effect is constructed. The dynamical behavior of the model is studied by using the basic reproduction number. The results demonstrate that the saturation effect within avian population and the psychological effect in human population cannot change the stability of equilibria but can affect the number of infected humans if the disease is prevalent. Numerical simulations are given to support the theoretical results and sensitivity analyses of the basic reproduction number in terms of model parameters that are performed to seek for effective control measures for avian influenza. PMID:25861378

  13. Clinical, epidemiological and virological characteristics of the first detected human case of avian influenza A(H5N6) virus

    PubMed Central

    Zhang, Rusheng; Chen, Tianmu; Ou, Xinhua; Liu, Ruchun; Yang, Yang; Ye, Wen; Chen, Jingfang; Yao, Dong; Sun, Biancheng; Zhang, Xixing; Zhou, Jianxiang; Sun, Yan; Chen, Faming; Wang, Shi-Ping

    2016-01-01

    A human infection with novel avian influenza A H5N6 virus emerged in Changsha city, China in February, 2014. This is the first detected human case among all human cases identified from 2014 to early 2016. We obtained and summarized clinical, epidemiological, and virological data from this patient. Complete genome of the virus was determined and compared to other avian influenza viruses via the construction of phylogenetic trees using the neighbor-joining approach. A girl aged five and half years developed fever and mild respiratory symptoms on Feb. 16, 2014 and visited hospital on Feb. 17. Throat swab specimens were obtained from the patient and a novel reassortant avian influenza A H5N6 virus was detected. All eight viral gene segments were of avian origin. The hemagglutinin (HA) and neuraminidase (NA) gene segments were closely related to A/duck/Sichuan/NCXN11/2014(H5N1) and A/chicken/Jiangxi/12782/2014(H10N6) viruses, respectively. The six internal genes were homologous to avian influenza A (H5N2) viruses isolated in duck from Jiangxi in China. This H5N6 virus has not gained genetic mutations necessary for human infection and was suggested to be sensitive to neuraminidase inhibitors, but resistant to adamantanes. Epidemiological investigation of the exposure history of the patient found that a live poultry market could be the source place of infection and the incubation period was 2–5 days. This novel reassortant Avian influenza A(H5N6) virus could be low pathogenic in humans. The prevalence and genetic evolution of this virus should be closely monitored. PMID:26973295

  14. Clinical, epidemiological and virological characteristics of the first detected human case of avian influenza A(H5N6) virus.

    PubMed

    Zhang, Rusheng; Chen, Tianmu; Ou, Xinhua; Liu, Ruchun; Yang, Yang; Ye, Wen; Chen, Jingfang; Yao, Dong; Sun, Biancheng; Zhang, Xixing; Zhou, Jianxiang; Sun, Yan; Chen, Faming; Wang, Shi-Ping

    2016-06-01

    A human infection with novel avian influenza A H5N6 virus emerged in Changsha city, China in February, 2014. This is the first detected human case among all human cases identified from 2014 to early 2016. We obtained and summarized clinical, epidemiological, and virological data from this patient. Complete genome of the virus was determined and compared to other avian influenza viruses via the construction of phylogenetic trees using the neighbor-joining approach. A girl aged five and half years developed fever and mild respiratory symptoms on Feb. 16, 2014 and visited hospital on Feb. 17. Throat swab specimens were obtained from the patient and a novel reassortant avian influenza A H5N6 virus was detected. All eight viral gene segments were of avian origin. The hemagglutinin (HA) and neuraminidase (NA) gene segments were closely related to A/duck/Sichuan/NCXN11/2014(H5N1) and A/chicken/Jiangxi/12782/2014(H10N6) viruses, respectively. The six internal genes were homologous to avian influenza A (H5N2) viruses isolated in duck from Jiangxi in China. This H5N6 virus has not gained genetic mutations necessary for human infection and was suggested to be sensitive to neuraminidase inhibitors, but resistant to adamantanes. Epidemiological investigation of the exposure history of the patient found that a live poultry market could be the source place of infection and the incubation period was 2-5days. This novel reassortant Avian influenza A(H5N6) virus could be low pathogenic in humans. The prevalence and genetic evolution of this virus should be closely monitored. PMID:26973295

  15. Analysis of human infectious avian influenza virus: hemagglutinin genetic characteristics in Asia and Africa from 2004 to 2009.

    PubMed

    Zhang, Jirong; Lei, Fumin

    2010-09-01

    In the present study, we used nucleotide and protein sequences of avian influenza virus H5N1, which were obtained in Asia and Africa, analyzed HA proteins using ClustalX1.83 and MEGA4.0, and built a genetic evolutionary tree of HA nucleotides. The analysis revealed that the receptor specificity amino acid of A/HK/213/2003, A/Turkey/65596/2006 and etc mutated into QNG, which could bind with á-2, 3 galactose and á-2, 6 galactose. A mutation might thus take place and lead to an outbreak of human infections of avian influenza virus. The mutations of HA protein amino acids from 2004 to 2009 coincided with human infections provided by the World Health Organization, indicating a "low-high-highest-high-low" pattern. We also found out that virus strains in Asia are from different origins: strains from Southeast Asia and East Asia are of the same origin, whereas those from West Asia, South Asia and Africa descend from one ancestor. The composition of the phylogenetic tree and mutations of key site amino acids in HA proteins reflected the fact that the majority of strains are regional and long term, and virus diffusions exist between China, Laos, Malaysia, Indonesia, Azerbaijan, Turkey and Iraq. We would advise that pertinent vaccines be developed and due attention be paid to the spread of viruses between neighboring countries and the dangers of virus mutation and evolution. PMID:21392344

  16. Adenovirus as a carrier for the development of influenza virus-free avian influenza vaccines

    PubMed Central

    Tang, De-chu C; Zhang, Jianfeng; Toro, Haroldo; Shi, Zhongkai; Van Kampen, Kent R

    2009-01-01

    A long-sought goal during the battle against avian influenza is to develop a new generation of vaccines capable of mass immunizing humans as well as poultry (the major source of avian influenza for human infections) in a timely manner. Although administration of the currently licensed influenza vaccine is effective in eliciting protective immunity against seasonal influenza, this approach is associated with a number of insurmountable problems for preventing an avian influenza pandemic. Many of the hurdles may be eliminated by developing new avian influenza vaccines that do not require the propagation of an influenza virus during vaccine production. Replication-competent adenovirus-free adenovirus vectors hold promise as a carrier for influenza virus-free avian influenza vaccines owing to their safety profile and rapid manufacture using cultured suspension cells in a serum-free medium. Simple and efficient mass-immunization protocols, including nasal spray for people and automated in ovo vaccination for poultry, convey another advantage for this class of vaccines. In contrast to parenteral injection of adenovirus vector, the potency of adenovirus-vectored nasal vaccine is not appreciably interfered by pre-existing immunity to adenovirus. PMID:19348562

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

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

  18. An update on avian influenza in Mexico.

    PubMed

    Villarreal-Chávez, C; Rivera-Cruz, E

    2003-01-01

    The avian influenza high-pathogenicity virus was eradicated in poultry of Mexico in a relatively short period by the use of inactivated emulsified vaccine, enforcing biosecurity, and controlling movement of poultry and poultry products. Mexico maintains a permanent and reliable monitoring program for AI. H5N2 is the only avian influenza subtype identified. It is possible to control and eradicate the avian influenza low-pathogenicity virus mainly by controlled depopulation of positive poultry, reinforcing biosecurity, and the use of vaccines. PMID:14575101

  19. USGS highly pathogenic avian influenza research strategy

    USGS Publications Warehouse

    Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

    2015-01-01

    Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

  20. Host-Specific and Segment-Specific Evolutionary Dynamics of Avian and Human Influenza A Viruses: A Systematic Review

    PubMed Central

    Kim, Kiyeon; Omori, Ryosuke; Ueno, Keisuke; Iida, Sayaka; Ito, Kimihito

    2016-01-01

    Understanding the evolutionary dynamics of influenza viruses is essential to control both avian and human influenza. Here, we analyze host-specific and segment-specific Tajima’s D trends of influenza A virus through a systematic review using viral sequences registered in the National Center for Biotechnology Information. To avoid bias from viral population subdivision, viral sequences were stratified according to their sampling locations and sampling years. As a result, we obtained a total of 580 datasets each of which consists of nucleotide sequences of influenza A viruses isolated from a single population of hosts at a single sampling site within a single year. By analyzing nucleotide sequences in the datasets, we found that Tajima’s D values of viral sequences were different depending on hosts and gene segments. Tajima’s D values of viruses isolated from chicken and human samples showed negative, suggesting purifying selection or a rapid population growth of the viruses. The negative Tajima’s D values in rapidly growing viral population were also observed in computer simulations. Tajima’s D values of PB2, PB1, PA, NP, and M genes of the viruses circulating in wild mallards were close to zero, suggesting that these genes have undergone neutral selection in constant-sized population. On the other hand, Tajima’s D values of HA and NA genes of these viruses were positive, indicating HA and NA have undergone balancing selection in wild mallards. Taken together, these results indicated the existence of unknown factors that maintain viral subtypes in wild mallards. PMID:26760775

  1. Ecology of avian influenza virus in birds.

    PubMed

    Causey, Douglas; Edwards, Scott V

    2008-02-15

    Avian influenza A virus (an orthomyxovirus) is a zoonotic pathogen with a natural reservoir entirely in birds. The influenza virus genome is an 8-segment single-stranded RNA with high potential for in situ recombination. Two segments code for the hemagglutinin (H) and neuraminidase (N) antigens used for host-cell entry. At present, 16 H and 9 N subtypes are known, for a total of 144 possible different influenza subtypes, each with potentially different host susceptibility. With >10,000 species of birds found in nearly every terrestrial and aquatic habitat, there are few places on earth where birds cannot be found. The avian immune system differs from that of humans in several important features, including asynchronous B and T lymphocyte systems and a polymorphic multigene immune complex, but little is known about the immunogenetics of pathogenic response. Postbreeding dispersal and migration and a naturally high degree of environmental vagility mean that wild birds have the potential to be vectors that transmit highly pathogenic variants great distances from the original sources of infection. PMID:18269325

  2. Testing of human specimens for the presence of highly pathogenic zoonotic avian influenza virus A(H5N1) in Poland in 2006-2008 - justified or unnecessary steps?

    PubMed

    Romanowska, Magdalena; Nowak, Iwona; Brydak, Lidia; Wojtyla, Andrzej

    2009-01-01

    Since 1997, human infections with highly pathogenic zoonotic avian influenza viruses have shown that the risk of influenza pandemic is significant. In Europe, infections caused by the highly pathogenic avian influenza A(H7N7) virus were confirmed in the human population in 2003 in the Netherlands. Moreover, outbreaks of A(H5N1) infections were observed in wild and farm birds in different European regions, including Poland in 2006-2008. This study presents 16 patients in Poland from whom clinical specimens were collected and tested for A(H5N1) highly pathogenic avian influenza. This article shows the results of laboratory tests and discusses the legitimacy of the collection and testing of the specimens. All patients were negative for A(H5N1) infection. Nevertheless, only two patients met clinical and epidemiological criteria from the avian influenza case definition. The conclusion is that there is still a strong necessity for increasing the awareness of medical and laboratory staff, as well as the awareness of some occupational groups about human infections with avian influenza viruses, including the importance of seasonal influenza vaccination. It should also be emphasized that in the case of patients suspected of being infected with avian influenza, the information about clinical symptoms is insufficient and must be accompanied by a wide epidemiological investigation. PMID:20047257

  3. Avian influenza: an emerging pandemic threat.

    PubMed

    Jin, Xian Wen; Mossad, Sherif B

    2005-12-01

    While we are facing the threat of an emerging pandemic from the current avian flu outbreak in Asia, we have learned important traits of the virus responsible for the 1918 Spanish influenza pandemic that made it so deadly. By using stockpiled antiviral drugs effectively and developing an effective vaccine, we can be in a better position than ever to mitigate the global impact of an avian influenza pandemic. PMID:16392727

  4. Swine influenza virus: zoonotic potential and vaccination strategies for the control of avian and swine influenzas.

    PubMed

    Thacker, Eileen; Janke, Bruce

    2008-02-15

    Influenza viruses are able to infect humans, swine, and avian species, and swine have long been considered a potential source of new influenza viruses that can infect humans. Swine have receptors to which both avian and mammalian influenza viruses bind, which increases the potential for viruses to exchange genetic sequences and produce new reassortant viruses in swine. A number of genetically diverse viruses are circulating in swine herds throughout the world and are a major cause of concern to the swine industry. Control of swine influenza is primarily through the vaccination of sows, to protect young pigs through maternally derived antibodies. However, influenza viruses continue to circulate in pigs after the decay of maternal antibodies, providing a continuing source of virus on a herd basis. Measures to control avian influenza in commercial poultry operations are dictated by the virulence of the virus. Detection of a highly pathogenic avian influenza (HPAI) virus results in immediate elimination of the flock. Low-pathogenic avian influenza viruses are controlled through vaccination, which is done primarily in turkey flocks. Maintenance of the current HPAI virus-free status of poultry in the United States is through constant surveillance of poultry flocks. Although current influenza vaccines for poultry and swine are inactivated and adjuvanted, ongoing research into the development of newer vaccines, such as DNA, live-virus, or vectored vaccines, is being done. Control of influenza virus infection in poultry and swine is critical to the reduction of potential cross-species adaptation and spread of influenza viruses, which will minimize the risk of animals being the source of the next pandemic. PMID:18269323

  5. Avian influenza: the political economy of disease control in Cambodia.

    PubMed

    Ear, Sophal

    2011-01-01

    Abstract In the wake of avian flu outbreaks in 2004, Cambodia received $45 million in commitments from international donors to help combat the spread of animal and human influenza, particularly avian influenza (H5N1). How countries leverage foreign aid to address the specific needs of donors and the endemic needs of the nation is a complex and nuanced issue throughout the developing world. Cambodia is a particularly compelling study in pandemic preparedness and the management of avian influenza because of its multilayered network of competing local, national, and global needs, and because the level of aid in Cambodia represents approximately $2.65 million per human case-a disproportionately high number when compared with neighbors Vietnam and Indonesia. This paper examines how the Cambodian government has made use of animal and human influenza funds to protect (or fail to protect) its citizens and the global community. It asks how effective donor and government responses were to combating avian influenza in Cambodia, and what improvements could be made at the local and international level to help prepare for and respond to future outbreaks. Based on original interviews, a field survey of policy stakeholders, and detailed examination of Cambodia's health infrastructure and policies, the findings illustrate that while pandemic preparedness has shown improvements since 2004, new outbreaks and human fatalities accelerated in 2011, and more work needs to be done to align the specific goals of funders with the endemic needs of developing nations. PMID:22702421

  6. Monitoring Avian Influenza A(H7N9) Virus through National Influenza-like Illness Surveillance, China

    PubMed Central

    Xu, Cuiling; Havers, Fiona; Wang, Lijie; Chen, Tao; Shi, Jinghong; Wang, Dayan; Yang, Jing; Yang, Lei; Widdowson, Marc-Alain

    2013-01-01

    In China during March 4–April 28, 2013, avian influenza A(H7N9) virus testing was performed on 20,739 specimens from patients with influenza-like illness in 10 provinces with confirmed human cases: 6 (0.03%) were positive, and increased numbers of unsubtypeable influenza-positive specimens were not seen. Careful monitoring and rapid characterization of influenza A(H7N9) and other influenza viruses remain critical. PMID:23879887

  7. Structure and Receptor Binding Preferences of Recombinant Hemagglutinins from Avian and Human H6 and H10 Influenza A Virus Subtypes

    PubMed Central

    Yang, Hua; Carney, Paul J.; Chang, Jessie C.; Villanueva, Julie M.

    2015-01-01

    ABSTRACT During 2013, three new avian influenza A virus subtypes, A(H7N9), A(H6N1), and A(H10N8), resulted in human infections. While the A(H7N9) virus resulted in a significant epidemic in China across 19 provinces and municipalities, both A(H6N1) and A(H10N8) viruses resulted in only a few human infections. This study focuses on the major surface glycoprotein hemagglutinins from both of these novel human viruses. The detailed structural and glycan microarray analyses presented here highlight the idea that both A(H6N1) and A(H10N8) virus hemagglutinins retain a strong avian receptor binding preference and thus currently pose a low risk for sustained human infections. IMPORTANCE Human infections with zoonotic influenza virus subtypes continue to be a great public health concern. We report detailed structural analysis and glycan microarray data for recombinant hemagglutinins from A(H6N1) and A(H10N8) viruses, isolated from human infections in 2013, and compare them with hemagglutinins of avian origin. This is the first structural report of an H6 hemagglutinin, and our results should further the understanding of these viruses and provide useful information to aid in the continuous surveillance of these zoonotic influenza viruses. PMID:25673707

  8. Avian influenza viruses that cause highly virulent infections in humans exhibit distinct replicative properties in contrast to human H1N1 viruses

    NASA Astrophysics Data System (ADS)

    Simon, Philippe F.; de La Vega, Marc-Antoine; Paradis, Éric; Mendoza, Emelissa; Coombs, Kevin M.; Kobasa, Darwyn; Beauchemin, Catherine A. A.

    2016-04-01

    Avian influenza viruses present an emerging epidemiological concern as some strains of H5N1 avian influenza can cause severe infections in humans with lethality rates of up to 60%. These have been in circulation since 1997 and recently a novel H7N9-subtyped virus has been causing epizootics in China with lethality rates around 20%. To better understand the replication kinetics of these viruses, we combined several extensive viral kinetics experiments with mathematical modelling of in vitro infections in human A549 cells. We extracted fundamental replication parameters revealing that, while both the H5N1 and H7N9 viruses replicate faster and to higher titers than two low-pathogenicity H1N1 strains, they accomplish this via different mechanisms. While the H7N9 virions exhibit a faster rate of infection, the H5N1 virions are produced at a higher rate. Of the two H1N1 strains studied, the 2009 pandemic H1N1 strain exhibits the longest eclipse phase, possibly indicative of a less effective neuraminidase activity, but causes infection more rapidly than the seasonal strain. This explains, in part, the pandemic strain’s generally slower growth kinetics and permissiveness to accept mutations causing neuraminidase inhibitor resistance without significant loss in fitness. Our results highlight differential growth properties of H1N1, H5N1 and H7N9 influenza viruses.

  9. Avian influenza viruses that cause highly virulent infections in humans exhibit distinct replicative properties in contrast to human H1N1 viruses

    PubMed Central

    Simon, Philippe F.; de La Vega, Marc-Antoine; Paradis, Éric; Mendoza, Emelissa; Coombs, Kevin M.; Kobasa, Darwyn; Beauchemin, Catherine A. A.

    2016-01-01

    Avian influenza viruses present an emerging epidemiological concern as some strains of H5N1 avian influenza can cause severe infections in humans with lethality rates of up to 60%. These have been in circulation since 1997 and recently a novel H7N9-subtyped virus has been causing epizootics in China with lethality rates around 20%. To better understand the replication kinetics of these viruses, we combined several extensive viral kinetics experiments with mathematical modelling of in vitro infections in human A549 cells. We extracted fundamental replication parameters revealing that, while both the H5N1 and H7N9 viruses replicate faster and to higher titers than two low-pathogenicity H1N1 strains, they accomplish this via different mechanisms. While the H7N9 virions exhibit a faster rate of infection, the H5N1 virions are produced at a higher rate. Of the two H1N1 strains studied, the 2009 pandemic H1N1 strain exhibits the longest eclipse phase, possibly indicative of a less effective neuraminidase activity, but causes infection more rapidly than the seasonal strain. This explains, in part, the pandemic strain’s generally slower growth kinetics and permissiveness to accept mutations causing neuraminidase inhibitor resistance without significant loss in fitness. Our results highlight differential growth properties of H1N1, H5N1 and H7N9 influenza viruses. PMID:27080193

  10. Avian influenza viruses that cause highly virulent infections in humans exhibit distinct replicative properties in contrast to human H1N1 viruses.

    PubMed

    Simon, Philippe F; de La Vega, Marc-Antoine; Paradis, Éric; Mendoza, Emelissa; Coombs, Kevin M; Kobasa, Darwyn; Beauchemin, Catherine A A

    2016-01-01

    Avian influenza viruses present an emerging epidemiological concern as some strains of H5N1 avian influenza can cause severe infections in humans with lethality rates of up to 60%. These have been in circulation since 1997 and recently a novel H7N9-subtyped virus has been causing epizootics in China with lethality rates around 20%. To better understand the replication kinetics of these viruses, we combined several extensive viral kinetics experiments with mathematical modelling of in vitro infections in human A549 cells. We extracted fundamental replication parameters revealing that, while both the H5N1 and H7N9 viruses replicate faster and to higher titers than two low-pathogenicity H1N1 strains, they accomplish this via different mechanisms. While the H7N9 virions exhibit a faster rate of infection, the H5N1 virions are produced at a higher rate. Of the two H1N1 strains studied, the 2009 pandemic H1N1 strain exhibits the longest eclipse phase, possibly indicative of a less effective neuraminidase activity, but causes infection more rapidly than the seasonal strain. This explains, in part, the pandemic strain's generally slower growth kinetics and permissiveness to accept mutations causing neuraminidase inhibitor resistance without significant loss in fitness. Our results highlight differential growth properties of H1N1, H5N1 and H7N9 influenza viruses. PMID:27080193

  11. Prevention and Treatment of Avian Influenza A Viruses in People

    MedlinePlus

    ... Research Making a Candidate Vaccine Virus Related Links Influenza Types Seasonal Avian Swine Variant Pandemic Other Get ... Button Past Newsletters Prevention and Treatment of Avian Influenza A Viruses in People Language: English Español ...

  12. Avian influenza vaccination in chickens and pigs with replication-competent adenovirus-free human recombinant adenovirus 5.

    PubMed

    Toro, Haroldo; van Ginkel, Frederik W; Tang, De-Chu C; Schemera, Bettina; Rodning, Soren; Newton, Joseph

    2010-03-01

    Protective immunity to avian influenza (AI) virus can be elicited in chickens by in ovo or intramuscular vaccination with replication-competent adenovirus (RCA)-free human recombinant adenovirus serotype 5 (Ad5) encoding AI virus H5 (AdTW68.H5) or H7 (AdCN94.H7) hemagglutinins. We evaluated bivalent in ovo vaccination with AdTW68.H5 and AdCN94.H7 and determined that vaccinated chickens developed robust hemagglutination inhibition (HI) antibody levels to both H5 and H7 AI strains. Additionally, we evaluated immune responses of 1-day-old chickens vaccinated via spray with AdCN94.H7. These birds showed increased immunoglobulin A responses in lachrymal fluids and increased interleukin-6 expression in Harderian gland-derived lymphocytes. However, specific HI antibodies were not detected in the sera of these birds. Because pigs might play a role as a "mixing vessel" for the generation of pandemic influenza viruses we explored the use of RCA-free adenovirus technology to immunize pigs against AI virus. Weanling piglets vaccinated intramuscularly with a single dose of RCA-free AdTW68.H5 developed strong systemic antibody responses 3 wk postvaccination. Intranasal application of AdTW68.H5 in piglets resulted in reduced vaccine coverage, i.e., 33% of pigs (2/6) developed an antibody response, but serum antibody levels in those successfully immunized animals were similar to intramuscularly vaccinated animals. PMID:20521636

  13. [Analysis of decrease in sensitivity in influenza A (H5N1) avian and human strains to neuraminidase inhibitors].

    PubMed

    Reina, J

    2008-03-01

    The options for efficient control of avian influenza A (H5N1) viruses include specific vaccination and antiviral prophylaxis and treatment. However, because H5N1 viruses undergo continuous antigen mutations, the production of a matched vaccine strain is currently not possible. Thus, during the early pandemic period, specific control measures would rely solely on antiviral drugs. Now only neuraminidase inhibitors (NIs) (zanamivir and oseltamivir) are considered for prophylaxis and therapy in patients with H5N1 infection. The sensitivies of H5N1 strains to the NIs fell into 3 groups. The clade I viruses isolated before 2004 were as sensitive to NIs than reference strains (first group). But the clade I viruses isolated from 2004 were 6 to 7-fold less sensitivity to NIs (second group). The clade II strains isolated from 2005 to 2007 demonstrated a 15 to 30 fold decrease in sensitivity to oseltamivir compared with clade I viruses (third group). The specific decrease in sensitivity to oseltamivir of both Cambodian and Indonesian clade 2 influenza H5N1 isolates is disturbing, especially because they maintain their pathogenicity and transmissibility in birds and are clearly pathogenic in humans. No altered sensitivity to zanamivir has been detected. Zanamivir may also play an important role in pandemic stockpiles. Because the clade 2 virus is now spread through parts of Europe and Africa, continued global collaboration and phenotypic testing of NIs sensitivity are critical for a future pandemic. PMID:18443931

  14. Different pH requirements are associated with divergent inhibitory effects of chloroquine on human and avian influenza A viruses

    PubMed Central

    Di Trani, Livia; Savarino, Andrea; Campitelli, Laura; Norelli, Sandro; Puzelli, Simona; D'Ostilio, Daniela; Vignolo, Edoardo; Donatelli, Isabella; Cassone, Antonio

    2007-01-01

    Chloroquine is a 4-aminoquinoline previously used in malaria therapy and now becoming an emerging investigational antiviral drug due to its broad spectrum of antiviral activities. To explore whether the low pH-dependency of influenza A viruses might affect the antiviral effects of chloroquine at clinically achievable concentrations, we tested the antiviral effects of this drug on selected human and avian viruses belonging to different subtypes and displaying different pH requirements. Results showed a correlation between the responses to chloroquine and NH4Cl, a lysosomotropic agent known to increase the pH of intracellular vesicles. Time-of-addition experiments showed that the inhibitory effect of chloroquine was maximal when the drug had been added at the time of infection and was lost after 2 h post-infection. This timing approximately corresponds to that of virus/cell fusion. Moreover, there was a clear correlation between the EC50 of chloroquine in vitro and the electrostatic potential of the HA subunit (HA2) mediating the virus/cell fusion process. Overall, the present study highlights the critical importance of a host cell factor such as intravesicular pH in determining the anti-influenza activity of chloroquine and other lysosomotropic agents. PMID:17477867

  15. Avian influenza surveillance of wild birds

    USGS Publications Warehouse

    Slota, Paul

    2007-01-01

    The President's National Strategy for Pandemic Influenza directs federal agencies to expand the surveillance of United States domestic livestock and wildlife to ensure early warning of hightly pathogenic avian influenza (HPAI) in the U.S. The immediate concern is a potential introduction of HPAI H5N1 virus into the U.S. The presidential directive resulted in the U.S. Interagency Strategic Plan for Early Detection of H5N1 Highly Pathogenic Avian Influenza in Wild Migratory Birds (referred to as the Wild Bird Surveillance Plan or the Plan).

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

    PubMed

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

    2015-01-01

    It has been documented that the epidemiological characteristics of human infections with H7N9 differ significantly between H5N1. However, potential factors that may explain the different spatial distributions remain unexplored. We use boosted regression tree (BRT) models to explore the association of agro-ecological, environmental and meteorological variables with the occurrence of human cases of H7N9 and H5N1, and map the probabilities of occurrence of human cases. Live poultry markets, density of human, coverage of built-up land, relative humidity and precipitation were significant predictors for both. In addition, density of poultry, coverage of shrub and temperature played important roles for human H7N9 infection, whereas human H5N1 infection was associated with coverage of forest and water body. Based on the risks and distribution of ecological characteristics which may facilitate the circulation of the two viruses, we found Yangtze River Delta and Pearl River Delta, along with a few spots on the southeast coastline, to be the high risk areas for H7N9 and H5N1. Additional, H5N1 risk spots were identified in eastern Sichuan and southern Yunnan Provinces. Surveillance of the two viruses needs to be enhanced in these high risk areas to reduce the risk of future epidemics of avian influenza in China. PMID:26691585

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

    PubMed Central

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

    2015-01-01

    It has been documented that the epidemiological characteristics of human infections with H7N9 differ significantly between H5N1. However, potential factors that may explain the different spatial distributions remain unexplored. We use boosted regression tree (BRT) models to explore the association of agro-ecological, environmental and meteorological variables with the occurrence of human cases of H7N9 and H5N1, and map the probabilities of occurrence of human cases. Live poultry markets, density of human, coverage of built-up land, relative humidity and precipitation were significant predictors for both. In addition, density of poultry, coverage of shrub and temperature played important roles for human H7N9 infection, whereas human H5N1 infection was associated with coverage of forest and water body. Based on the risks and distribution of ecological characteristics which may facilitate the circulation of the two viruses, we found Yangtze River Delta and Pearl River Delta, along with a few spots on the southeast coastline, to be the high risk areas for H7N9 and H5N1. Additional, H5N1 risk spots were identified in eastern Sichuan and southern Yunnan Provinces. Surveillance of the two viruses needs to be enhanced in these high risk areas to reduce the risk of future epidemics of avian influenza in China. PMID:26691585

  18. The distinct binding properties between avian/human influenza A virus NS1 and Postsynaptic density protein-95 (PSD-95), and inhibition of nitric oxide production

    PubMed Central

    2011-01-01

    Background The NS1 protein of influenza A virus is able to bind with many proteins that affect cellular signal transduction and protein synthesis in infected cells. The NS1 protein consists of approximately 230 amino acids and the last 4 amino acids of the NS1 C-terminal form a PDZ binding motif. Postsynaptic Density Protein-95 (PSD-95), which is mainly expressed in neurons, has 3 PDZ domains. We hypothesise that NS1 binds to PSD-95, and this binding is able to affect neuronal function. Result We conducted a yeast two-hybrid analysis, GST-pull down assays and co-immunoprecipitations to detect the interaction between NS1 and PSD-95. The results showed that NS1 of avian influenza virus H5N1 (A/chicken/Guangdong/1/2005) is able to bind to PSD-95, whereas NS1 of human influenza virus H1N1 (A/Shantou/169/2006) is unable to do so. The results also revealed that NS1 of H5N1 significantly reduces the production of nitric oxide (NO) in rat hippocampal neurons. Conclusion In summary, our study indicates that NS1 of influenza A virus can bind with neuronal PSD-95, and the avian H5N1 and human H1N1 influenza A viruses possess distinct binding properties. PMID:21668967

  19. Surveillance of avian influenza viruses in Papua New Guinean poultry, June 2011 to April 2012

    PubMed Central

    Jonduo, Marinjho; Wong, Sook-San; Kapo, Nime; Ominipi, Paskalis; Abdad, Mohammad; Siba, Peter; McKenzie, Pamela; Webby, Richard

    2013-01-01

    We investigated the circulation of avian influenza viruses in poultry populations throughout Papua New Guinea to assess the risk to the poultry industry and human health. Oropharyngeal swabs, cloacal swabs and serum were collected from 537 poultry from 14 provinces of Papua New Guinea over an 11–month period (June 2011 through April 2012). Virological and serological investigations were undertaken to determine the prevalence of avian influenza viruses. Neither influenza A viruses nor antibodies were detected in any of the samples. This study demonstrated that avian influenza viruses were not circulating at detectable levels in poultry populations in Papua New Guinea during the sampling period. However, avian influenza remains a significant risk to Papua New Guinea due to the close proximity of countries having previously reported highly pathogenic avian influenza viruses and the low biosecurity precautions associated with the rearing of most poultry populations in the country. PMID:24478918

  20. Avian Influenza: a global threat needing a global solution

    PubMed Central

    Koh, GCH; Wong, TY; Cheong, SK; Koh, DSQ

    2008-01-01

    There have been three influenza pandemics since the 1900s, of which the 1919–1919 flu pandemic had the highest mortality rates. The influenza virus infects both humans and birds, and mutates using two mechanisms: antigenic drift and antigenic shift. Currently, the H5N1 avian flu virus is limited to outbreaks among poultry and persons in direct contact to infected poultry, but the mortality rate among infected humans is high. Avian influenza (AI) is endemic in Asia as a result of unregulated poultry rearing in rural areas. Such birds often live in close proximity to humans and this increases the chance of genetic re-assortment between avian and human influenza viruses which may produce a mutant strain that is easily transmitted between humans. Once this happens, a global pandemic is likely. Unlike SARS, a person with influenza infection is contagious before the onset of case-defining symptoms which limits the effectiveness of case isolation as a control strategy. Researchers have shown that carefully orchestrated of public health measures could potentially limit the spread of an AI pandemic if implemented soon after the first cases appear. To successfully contain and control an AI pandemic, both national and global strategies are needed. National strategies include source surveillance and control, adequate stockpiles of anti-viral agents, timely production of flu vaccines and healthcare system readiness. Global strategies such as early integrated response, curbing the disease outbreak at source, utilization of global resources, continuing research and open communication are also critical. PMID:19014538

  1. Impact of host genes on resistance to avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    H5N1 high pathogenicity avian influenza (HPAI) virus has caused massive outbreaks of infection and disease in poultry, significant numbers of infections in wild aquatic birds and some infections in mammals and humans in Asia, Europe and Africa. The primary intervention strategy in poultry within de...

  2. The prevention and control of avian influenza: The avian influenza coordinated agriculture project1

    PubMed Central

    Cardona, C.; Slemons, R.; Perez, D.

    2015-01-01

    The Avian Influenza Coordinated Agriculture Project (AICAP) entitled “Prevention and Control of Avian Influenza in the US” strives to be a significant point of reference for the poultry industry and the general public in matters related to the biology, risks associated with, and the methods used to prevent and control avian influenza. To this end, AICAP has been remarkably successful in generating research data, publications through an extensive network of university- and agency-based researchers, and extending findings to stakeholders. An overview of the highlights of AICAP research is presented. PMID:19276431

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

    PubMed Central

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

    2015-01-01

    Understanding the mechanism of protective antibody recognition against highly pathogenic avian influenza A virus H5N1 in humans is critical for the development of effective therapies and vaccines. Here we report the crystal structure of three H5-specific human monoclonal antibodies bound to the globular head of hemagglutinin (HA) with distinct epitope specificities, neutralization potencies and breadth. A structural and functional analysis of these epitopes combined with those reported elsewhere identifies four major vulnerable sites on the globular head of H5N1 HA. Chimeric and vulnerable site-specific mutant pseudoviruses are generated to delineate broad neutralization specificities of convalescent sera from two individuals who recovered from the infection with H5N1 virus. Our results show that the four vulnerable sites on the globular head rather than the stem region are the major neutralizing targets, suggesting that during natural H5N1 infection neutralizing antibodies against the globular head work in concert to provide protective antibody-mediated immunity. PMID:26635249

  4. Microevolution of Highly Pathogenic Avian Influenza A(H5N1) Viruses Isolated from Humans, Egypt, 2007–2011

    PubMed Central

    Younan, Mary; Poh, Mee Kian; Elassal, Emad; Davis, Todd; Rivailler, Pierre; Balish, Amanda L.; Simpson, Natosha; Jones, Joyce; Deyde, Varough; Loughlin, Rosette; Perry, Ije; Gubareva, Larisa; ElBadry, Maha A.; Truelove, Shaun; Gaynor, Anne M.; Mohareb, Emad; Amin, Magdy; Cornelius, Claire; Pimentel, Guillermo; Earhart, Kenneth; Naguib, Amel; Abdelghani, Ahmed S.; Refaey, Samir; Klimov, Alexander I.; Kandeel, Amr

    2013-01-01

    We analyzed highly pathogenic avian influenza A(H5N1) viruses isolated from humans infected in Egypt during 2007–2011. All analyzed viruses evolved from the lineage of subtype H5N1 viruses introduced into Egypt in 2006; we found minimal evidence of reassortment and no exotic introductions. The hemagglutinin genes of the viruses from 2011 formed a monophyletic group within clade 2.2.1 that also included human viruses from 2009 and 2010 and contemporary viruses from poultry; this finding is consistent with zoonotic transmission. Although molecular markers suggestive of decreased susceptibility to antiviral drugs were detected sporadically in the neuraminidase and matrix 2 proteins, functional neuraminidase inhibition assays did not identify resistant viruses. No other mutations suggesting a change in the threat to public health were detected in the viral proteomes. However, a comparison of representative subtype H5N1 viruses from 2011 with older subtype H5N1 viruses from Egypt revealed substantial antigenic drift. PMID:23260983

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

    PubMed

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

    2015-01-01

    Understanding the mechanism of protective antibody recognition against highly pathogenic avian influenza A virus H5N1 in humans is critical for the development of effective therapies and vaccines. Here we report the crystal structure of three H5-specific human monoclonal antibodies bound to the globular head of hemagglutinin (HA) with distinct epitope specificities, neutralization potencies and breadth. A structural and functional analysis of these epitopes combined with those reported elsewhere identifies four major vulnerable sites on the globular head of H5N1 HA. Chimeric and vulnerable site-specific mutant pseudoviruses are generated to delineate broad neutralization specificities of convalescent sera from two individuals who recovered from the infection with H5N1 virus. Our results show that the four vulnerable sites on the globular head rather than the stem region are the major neutralizing targets, suggesting that during natural H5N1 infection neutralizing antibodies against the globular head work in concert to provide protective antibody-mediated immunity. PMID:26635249

  6. Comparison of pathogenicities of H7 avian influenza viruses via intranasal and conjunctival inoculation in cynomolgus macaques.

    PubMed

    Shichinohe, Shintaro; Itoh, Yasushi; Nakayama, Misako; Ozaki, Hiroichi; Soda, Kosuke; Ishigaki, Hirohito; Okamatsu, Masatoshi; Sakoda, Yoshihiro; Kida, Hiroshi; Ogasawara, Kazumasa

    2016-06-01

    The outbreak of H7N9 low pathogenic avian influenza viruses in China has attracted attention to H7 influenza virus infection in humans. Since we have shown that the pathogenicity of H1N1 and H5N1 influenza viruses in macaques was almost the same as that in humans, we compared the pathogenicities of H7 avian influenza viruses in cynomolgus macaques via intranasal and conjunctival inoculation, which mimics natural infection in humans. H7N9 virus, as well as H7N7 highly pathogenic avian influenza virus, showed more efficient replication and higher pathogenicity in macaques than did H7N1 and H7N3 highly pathogenic avian influenza viruses. These results are different from pathogenicity in chickens as reported previously. Therefore, our results obtained in macaques help to estimate the pathogenicity of H7 avian influenza viruses in humans. PMID:26994587

  7. Avian influenza: Myth or mass murder?

    PubMed Central

    Louie, Carol

    2005-01-01

    The purpose of the present article was to determine whether avian influenza (AI) is capable of causing a pandemic. Using research from a variety of medical journals, books and texts, the present paper evaluates the probability of the AI virus becoming sufficiently virulent to pose a global threat. Previous influenza A pandemics from the past century are reviewed, focusing on the mortality rate and the qualities of the virus that distinguish it from other viruses. Each of the influenza A viruses reviewed were classified as pandemic because they met three key criteria: first, the viruses were highly pathogenic within the human population; second, the viruses were easily transmissible from person to person; and finally, the viruses were novel, such that a large proportion of the population was susceptible to infection. Information about the H5N1 subtype of AI has also been critically assessed. Evidence suggests that this AI subtype is both novel and highly pathogenic. The mortality rate from epidemics in Thailand in 2004 was as high as 66%. Clearly, this virus is aggressive. It causes a high death rate, proving that humans have a low immunity to the disease. To date, there has been little evidence to suggest that AI can spread among humans. There have been cases where the virus has transferred from birds to humans, in settings such as farms or open markets with live animal vending. If AI were to undergo a genetic reassortment that allowed itself to transmit easily from person to person, then a serious pandemic could ensue, resulting in high morbidity and mortality. Experts at the World Health Organization and the United States Centers for Disease Control and Prevention agree that AI has the potential to undergo an antigenic shift, thus triggering the next pandemic. PMID:18159544

  8. Avian Influenza A Viruses: Evolution and Zoonotic Infection.

    PubMed

    Kim, Se Mi; Kim, Young-Il; Pascua, Philippe Noriel Q; Choi, Young Ki

    2016-08-01

    Although efficient human-to-human transmission of avian influenza virus has yet to be seen, in the past two decades avian-to-human transmission of influenza A viruses has been reported. Influenza A/H5N1, in particular, has repeatedly caused human infections associated with high mortality, and since 1998 the virus has evolved into many clades of variants with significant antigenic diversity. In 2013, three (A/H7N9, A/H6N1, and A/H10N8) novel avian influenza viruses (AIVs) breached the animal-human host species barrier in Asia. In humans, roughly 35% of A/H7N9-infected patients succumbed to the zoonotic infection, and two of three A/H10N8 human infections were also lethal; however, neither of these viruses cause influenza-like symptoms in poultry. While most of these cases were associated with direct contact with infected poultry, some involved sustained human-to-human transmission. Thus, these events elicited concern regarding potential AIV pandemics. This article reviews the human incursions associated with AIV variants and the potential role of pigs as an intermediate host that may hasten AIV evolution. In addition, we discuss the known influenza A virus virulence and transmission factors and their evaluation in animal models. With the growing number of human AIV infections, constant vigilance for the emergence of novel viruses is of utmost importance. In addition, careful characterization and pathobiological assessment of these novel variants will help to identify strains of particular concern for future pandemics. PMID:27486732

  9. Troop education and avian influenza surveillance in military barracks in Ghana, 2011

    PubMed Central

    2012-01-01

    Background Influenza A viruses that cause highly pathogenic avian influenza (HPAI) also infect humans. In many developing countries such as Ghana, poultry and humans live in close proximity in both the general and military populations, increasing risk for the spread of HPAI from birds to humans. Respiratory infections such as influenza are especially prone to rapid spread among military populations living in close quarters such as barracks making this a key population for targeted avian influenza surveillance and public health education. Method Twelve military barracks situated in the coastal, tropical rain forest and northern savannah belts of the country were visited and the troops and their families educated on pandemic avian influenza. Attendants at each site was obtained from the attendance sheet provided for registration. The seminars focused on zoonotic diseases, influenza surveillance, pathogenesis of avian influenza, prevention of emerging infections and biosecurity. To help direct public health policies, a questionnaire was used to collect information on animal populations and handling practices from 102 households in the military barracks. Cloacal and tracheal samples were taken from 680 domestic and domesticated wild birds and analysed for influenza A using molecular methods for virus detection. Results Of the 1028 participants that took part in the seminars, 668 (65%) showed good knowledge of pandemic avian influenza and the risks associated with its infection. Even though no evidence of the presence of avian influenza (AI) infection was found in the 680 domestic and wild birds sampled, biosecurity in the households surveyed was very poor. Conclusion Active surveillance revealed that there was no AI circulation in the military barracks in April 2011. Though participants demonstrated good knowledge of pandemic avian influenza, biosecurity practices were minimal. Sustained educational programs are needed to further strengthen avian influenza surveillance

  10. Viral vectors for avian influenza vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Prior to 2003, vaccines against avian influenza (AI) had limited, individual country or regional use in poultry. In late 2003, H5N1 high pathogenicity (HP) AI spread from China to multiple Southeast Asian countries, and to Europe during 2005 and Africa during 2006, challenging governments and all p...

  11. Rapid molecular diagnostic tools for avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An accurate and early diagnosis of a foreign animal disease is crucial for rapid control and eradication of an outbreak in a country previously free of the disease. Historically many animal diseases have been controlled based solely on clinical signs of disease. However with avian influenza virus ...

  12. Pathobiology of avian influenza in domestic ducks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Domestic ducks are an important source of food and income in many parts of the world. The susceptibility of domestic ducks to avian influenza (AI) viruses varies depending on many factors, including the species and the age of the ducks, the virus strain, and management practices. Although wild wat...

  13. Avian influenza vaccines and therapies for poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines have been used in avian influenza (AI) control programs to prevent, manage or eradicate AI from poultry and other birds. The best protection is produced from the humoral response against the hemagglutinin (HA) protein. A variety of vaccines have been developed and tested under experimenta...

  14. Avian influenza vaccines and vaccination for poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines against avian influenza (AI) have had more limited use in poultry than vaccines against other poultry diseases such as Newcastle disease (ND) and infectious bronchitis, and have been used more commonly in the developing world. Over the past 40 years, AI vaccines have been primarily based o...

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

    PubMed

    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. THE MOLECULAR BIOLOGY OF AVIAN INFLUENZA VIRUS IN SHORT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza virus (AIV) is an important pathogen of poultry as it can cause severe economic losses through disease, including respiratory signs and mortality, and effects on trade. Avian influenza virus is classified as type A influenza, which is a member of the orthomyxoviridae family. Charact...

  17. Early apoptosis of porcine alveolar macrophages limits avian influenza virus replication and pro-inflammatory dysregulation

    PubMed Central

    Chang, Pengxiang; Kuchipudi, Suresh V.; Mellits, Kenneth H.; Sebastian, Sujith; James, Joe; Liu, Jinhua; Shelton, Holly; Chang, Kin-Chow

    2015-01-01

    Pigs are evidently more resistant to avian than swine influenza A viruses, mediated in part through frontline epithelial cells and alveolar macrophages (AM). Although porcine AM (PAM) are crucial in influenza virus control, their mode of control is unclear. To gain insight into the possible role of PAM in the mediation of avian influenza virus resistance, we compared the host effects and replication of two avian (H2N3 and H6N1) and three mammalian (swine H1N1, human H1N1 and pandemic H1N1) influenza viruses in PAM. We found that PAM were readily susceptible to initial infection with all five avian and mammalian influenza viruses but only avian viruses caused early and extensive apoptosis (by 6 h of infection) resulting in reduced virus progeny and moderated pro-inflammation. Full length viral PB1-F2 present only in avian influenza viruses is a virulence factor that targets AM for mitochondrial-associated apoptotic cell death. With the use of reverse genetics on an avian H5N1 virus, we found that full length PB1-F2 contributed to increased apoptosis and pro-inflammation but not to reduced virus replication. Taken together, we propose that early apoptosis of PAM limits the spread of avian influenza viruses and that PB1-F2 could play a contributory role in the process. PMID:26642934

  18. Early apoptosis of porcine alveolar macrophages limits avian influenza virus replication and pro-inflammatory dysregulation.

    PubMed

    Chang, Pengxiang; Kuchipudi, Suresh V; Mellits, Kenneth H; Sebastian, Sujith; James, Joe; Liu, Jinhua; Shelton, Holly; Chang, Kin-Chow

    2015-01-01

    Pigs are evidently more resistant to avian than swine influenza A viruses, mediated in part through frontline epithelial cells and alveolar macrophages (AM). Although porcine AM (PAM) are crucial in influenza virus control, their mode of control is unclear. To gain insight into the possible role of PAM in the mediation of avian influenza virus resistance, we compared the host effects and replication of two avian (H2N3 and H6N1) and three mammalian (swine H1N1, human H1N1 and pandemic H1N1) influenza viruses in PAM. We found that PAM were readily susceptible to initial infection with all five avian and mammalian influenza viruses but only avian viruses caused early and extensive apoptosis (by 6 h of infection) resulting in reduced virus progeny and moderated pro-inflammation. Full length viral PB1-F2 present only in avian influenza viruses is a virulence factor that targets AM for mitochondrial-associated apoptotic cell death. With the use of reverse genetics on an avian H5N1 virus, we found that full length PB1-F2 contributed to increased apoptosis and pro-inflammation but not to reduced virus replication. Taken together, we propose that early apoptosis of PAM limits the spread of avian influenza viruses and that PB1-F2 could play a contributory role in the process. PMID:26642934

  19. Avian influenza in shorebirds: experimental infection of ruddy turnstones (Arenaria interpres) with avian influenza virus

    USGS Publications Warehouse

    Hall, Jeffrey S.; Krauss, Scott; Franson, J. Christian; TeSlaa, Joshua L.; Nashold, Sean W.; Stallknecht, David E.; Webby, Richard J.; Webster, Robert G.

    2013-01-01

    Background: Low pathogenic avian influenza viruses (LPAIV) have been reported in shorebirds, especially at Delaware Bay, USA, during spring migration. However, data on patterns of virus excretion, minimal infectious doses, and clinical outcome are lacking. The ruddy turnstone (Arenaria interpres) is the shorebird species with the highest prevalence of influenza virus at Delaware Bay. Objectives: The primary objective of this study was to experimentally assess the patterns of influenza virus excretion, minimal infectious doses, and clinical outcome in ruddy turnstones. Methods: We experimentally challenged ruddy turnstones using a common LPAIV shorebird isolate, an LPAIV waterfowl isolate, or a highly pathogenic H5N1 avian influenza virus. Cloacal and oral swabs and sera were analyzed from each bird. Results: Most ruddy turnstones had pre-existing antibodies to avian influenza virus, and many were infected at the time of capture. The infectious doses for each challenge virus were similar (103·6–104·16 EID50), regardless of exposure history. All infected birds excreted similar amounts of virus and showed no clinical signs of disease or mortality. Influenza A-specific antibodies remained detectable for at least 2 months after inoculation. Conclusions: These results provide a reference for interpretation of surveillance data, modeling, and predicting the risks of avian influenza transmission and movement in these important hosts.

  20. Avian influenza virus and free-ranging wild birds

    USGS Publications Warehouse

    Dierauf, Leslie A.; Karesh, W.B.; Ip, Hon S.; Gilardi, K.V.; Fischer, John R.

    2006-01-01

    Recent media and news reports and other information implicate wild birds in the spread of highly pathogenic avian influenza in Asia and Eastern Europe. Although there is little information concerning highly pathogenic avian influenza viruses in wild birds, scientists have amassed a large amount of data on low-pathogenicity avian influenza viruses during decades of research with wild birds. This knowledge can provide sound guidance to veterinarians, public health professionals, the general public, government agencies, and other entities with concerns about avian influenza.

  1. A cross-sectional study of avian influenza in one district of Guangzhou, 2013.

    PubMed

    Zhang, Haiming; Peng, Cong; Duan, Xiaodong; Shen, Dan; Lan, Guanghua; Xiao, Wutao; Tan, Hai; Wang, Ling; Hou, Jialei; Zhu, Jiancui; He, Riwen; Zhang, Haibing; Zheng, Lilan; Yang, Jianyu; Zhang, Zhen; Zhou, Zhiwei; Li, Wenhua; Hu, Mailing; Zhong, Jinhui; Chen, Yuhua

    2014-01-01

    Since Feb, 2013, more than 100 human beings had been infected with novel H7N9 avian influenza virus. As of May 2013, several H7N9 viruses had been found in retail live bird markets (LBMs) in Guangdong province of southern China where several human cases were confirmed later. However, the real avian influenza virus infection status especially H7N9 in Guangzhou remains unclear. Therefore, a cross-sectional study of avian influenza in commercial poultry farms, the wholesale LBM and retail LBMs in one district of Guangzhou was conducted from October to November, 2013. A total of 1505 cloacal and environmental samples from 52 commercial poultry farms, 1 wholesale LBM and 18 retail LBMs were collected and detected using real-time RT-PCR for type A, H7, H7N9 and H9 subtype avian influenza virus, respectively. Of all the flocks randomly sampled, 6 farms, 12 vendors of the wholesale LBM and 18 retail LBMs were type A avian influenza virus positive with 0, 3 and 11 positive for H9, respectively. The pooled prevalence and individual prevalence of type A avian influenza virus were 33.9% and 7.9% which for H9 subtype was 7.6% and 1.6%, respectively. None was H7 and H7N9 subtype virus positive. Different prevalence and prevalence ratio were found in different poultry species with partridges having the highest prevalence for both type A and H9 subtype avian influenza virus. Our results suggest that LBM may have a higher risk for sustaining and transmission of avian influenza virus than commercial poultry farms. The present study also indicates that different species may play different roles in the evolution and transmission of avian influenza virus. Therefore, risk-based surveillance and management measures should be conducted in future in this area. PMID:25356738

  2. Mycophenolic acid, an immunomodulator, has potent and broad-spectrum in vitro antiviral activity against pandemic, seasonal and avian influenza viruses affecting humans.

    PubMed

    To, Kelvin K W; Mok, Ka-Yi; Chan, Andy S F; Cheung, Nam N; Wang, Pui; Lui, Yin-Ming; Chan, Jasper F W; Chen, Honglin; Chan, Kwok-Hung; Kao, Richard Y T; Yuen, Kwok-Yung

    2016-08-01

    Immunomodulators have been shown to improve the outcome of severe pneumonia. We have previously shown that mycophenolic acid (MPA), an immunomodulator, has antiviral activity against influenza A/WSN/1933(H1N1) using a high-throughput chemical screening assay. This study further investigated the antiviral activity and mechanism of action of MPA against contemporary clinical isolates of influenza A and B viruses. The 50 % cellular cytotoxicity (CC50) of MPA in Madin Darby canine kidney cell line was over 50 µM. MPA prevented influenza virus-induced cell death in the cell-protection assay, with significantly lower IC50 for influenza B virus B/411 than that of influenza A(H1N1)pdm09 virus H1/415 (0.208 vs 1.510 µM, P=0.0001). For H1/415, MPA interfered with the early stage of viral replication before protein synthesis. For B/411, MPA may also act at a later stage since MPA was active against B/411 even when added 12 h post-infection. Virus-yield reduction assay showed that the replication of B/411 was completely inhibited by MPA at concentrations ≥0.78 µM, while there was a dose-dependent reduction of viral titer for H1/415. The antiviral effect of MPA was completely reverted by guanosine supplementation. Plaque reduction assay showed that MPA had antiviral activity against eight different clinical isolates of A(H1N1), A(H3N2), A(H7N9) and influenza B viruses (IC50 <1 µM). In summary, MPA has broad-spectrum antiviral activity against human and avian-origin influenza viruses, in addition to its immunomodulatory activity. Together with a high chemotherapeutic index, the use of MPA as an antiviral agent should be further investigated in vivo. PMID:27259985

  3. Avian Influenza A(H5N1) Virus in Egypt

    PubMed Central

    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

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

    PubMed

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

    2016-03-01

    In Egypt, avian influenza A subtype H5N1 and H9N2 viruses are enzootic in poultry. The control plan devised by veterinary authorities in Egypt to prevent infections in poultry focused mainly on vaccination and ultimately failed. Recently, widespread H5N1 infections in poultry and a substantial increase in the number of human cases of H5N1 infection were observed. We summarize surveillance data from 2009 through 2014 and show that avian influenza viruses are established in poultry in Egypt and are continuously evolving genetically and antigenically. We also discuss the epidemiology of human infection with avian influenza in Egypt and describe how the true burden of disease is underestimated. We discuss the failures of relying on vaccinating poultry as the sole intervention tool. We conclude by highlighting the key components that need to be included in a new strategy to control avian influenza infections in poultry and humans in Egypt. PMID:26886164

  5. Detection of Evolutionarily Distinct Avian Influenza A Viruses in Antarctica

    PubMed Central

    Vijaykrishna, Dhanasekaran; Butler, Jeffrey; Baas, Chantal; Maurer-Stroh, Sebastian; Silva-de-la-Fuente, M. Carolina; Medina-Vogel, Gonzalo; Olsen, Bjorn; Kelso, Anne; Barr, Ian G.; González-Acuña, Daniel

    2014-01-01

    ABSTRACT Distinct lineages of avian influenza viruses (AIVs) are harbored by spatially segregated birds, yet significant surveillance gaps exist around the globe. Virtually nothing is known from the Antarctic. Using virus culture, molecular analysis, full genome sequencing, and serology of samples from Adélie penguins in Antarctica, we confirmed infection by H11N2 subtype AIVs. Their genetic segments were distinct from all known contemporary influenza viruses, including South American AIVs, suggesting spatial separation from other lineages. Only in the matrix and polymerase acidic gene phylogenies did the Antarctic sequences form a sister relationship to South American AIVs, whereas distant phylogenetic relationships were evident in all other gene segments. Interestingly, their neuraminidase genes formed a distant relationship to all avian and human influenza lineages, and the polymerase basic 1 and polymerase acidic formed a sister relationship to the equine H3N8 influenza virus lineage that emerged during 1963 and whose avian origins were previously unknown. We also estimated that each gene segment had diverged for 49 to 80 years from its most closely related sequences, highlighting a significant gap in our AIV knowledge in the region. We also show that the receptor binding properties of the H11N2 viruses are predominantly avian and that they were unable to replicate efficiently in experimentally inoculated ferrets, suggesting their continuous evolution in avian hosts. These findings add substantially to our understanding of both the ecology and the intra- and intercontinental movement of Antarctic AIVs and highlight the potential risk of an incursion of highly pathogenic AIVs into this fragile environment. PMID:24803521

  6. Avian Influenza Virus and DIVA Strategies.

    PubMed

    Hasan, Noor Haliza; Ignjatovic, Jagoda; Peaston, Anne; Hemmatzadeh, Farhid

    2016-05-01

    Vaccination is becoming a more acceptable option in the effort to eradicate avian influenza viruses (AIV) from commercial poultry, especially in countries where AIV is endemic. The main concern surrounding this option has been the inability of the conventional serological tests to differentiate antibodies produced due to vaccination from antibodies produced in response to virus infection. In attempts to address this issue, at least six strategies have been formulated, aiming to differentiate infected from vaccinated animals (DIVA), namely (i) sentinel birds, (ii) subunit vaccine, (iii) heterologous neuraminidase (NA), (iv) nonstructural 1 (NS1) protein, (v) matrix 2 ectodomain (M2e) protein, and (vi) haemagglutinin subunit 2 (HA2) glycoprotein. This short review briefly discusses the strengths and limitations of these DIVA strategies, together with the feasibility and practicality of the options as a part of the surveillance program directed toward the eventual eradication of AIV from poultry in countries where highly pathogenic avian influenza is endemic. PMID:26900835

  7. Origin of the European avian-like swine influenza viruses.

    PubMed

    Krumbholz, Andi; Lange, Jeannette; Sauerbrei, Andreas; Groth, Marco; Platzer, Matthias; Kanrai, Pumaree; Pleschka, Stephan; Scholtissek, Christoph; Büttner, Mathias; Dürrwald, Ralf; Zell, Roland

    2014-11-01

    The avian-like swine influenza viruses emerged in 1979 in Belgium and Germany. Thereafter, they spread through many European swine-producing countries, replaced the circulating classical swine H1N1 influenza viruses, and became endemic. Serological and subsequent molecular data indicated an avian source, but details remained obscure due to a lack of relevant avian influenza virus sequence data. Here, the origin of the European avian-like swine influenza viruses was analysed using a collection of 16 European swine H1N1 influenza viruses sampled in 1979-1981 in Germany, the Netherlands, Belgium, Italy and France, as well as several contemporaneous avian influenza viruses of various serotypes. The phylogenetic trees suggested a triple reassortant with a unique genotype constellation. Time-resolved maximum clade credibility trees indicated times to the most recent common ancestors of 34-46 years (before 2008) depending on the RNA segment and the method of tree inference. PMID:25073465

  8. Evaluating the cell mediated immune response of avian species to avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The measurement of avian cellular immunity is critical to understanding the role and regulation of avian lymphocytes following avian influenza virus infection. Although the ability to measure avian T cell responses has steadily increased over the last few years, few studies have examined the role o...

  9. Clinical Characteristics of 26 Human Cases of Highly Pathogenic Avian Influenza A (H5N1) Virus Infection in China

    PubMed Central

    Xiang, Nijuan; Zhou, Lei; Huai, Yang; Feng, Luzhao; Peng, Zhibin; Li, Zhongjie; Xu, Cuiling; Li, Junhua; Hu, Chengping; Li, Qun; Xu, Xiaoling; Liu, Xuecheng; Liu, Zigui; Xu, Longshan; Chen, Yusheng; Luo, Huiming; Wei, Liping; Zhang, Xianfeng; Xin, Jianbao; Guo, Junqiao; Wang, Qiuyue; Yuan, Zhengan; Zhou, Longnv; Zhang, Kunzhao; Zhang, Wei; Yang, Jinye; Zhong, Xiaoning; Xia, Shichang; Li, Lanjuan; Cheng, Jinquan; Ma, Erdang; He, Pingping; Lee, Shui Shan; Wang, Yu; Uyeki, Timothy M.; Yang, Weizhong

    2008-01-01

    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 (64.5×109 cells/L vs 93.0×109 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. PMID:18716658

  10. Impact of live poultry market closure in reducing bird-to-human transmission of avian influenza A(H7N9) virus: an ecological study

    PubMed Central

    Yu, Hongjie; Wu, Joseph T.; Cowling, Benjamin J.; Liao, Qiaohong; Fang, Vicky J.; Zhou, Sheng; Wu, Peng; Zhou, Hang; Lau, Eric H. Y.; Guo, Danhuai; Ni, Michael Y.; Peng, Zhibin; Feng, Luzhao; Jiang, Hui; Luo, Huiming; Li, Qun; Feng, Zijian; Wang, Yu; Yang, Weizhong; Leung, Gabriel M.

    2014-01-01

    Background A novel influenza A(H7N9) virus has emerged in China during the past few months. Inter-species zoonotic transmission appears to be the predominant route of spread. Live poultry markets (LPMs) in the major cities of Shanghai, Hangzhou, Huzhou and Nanjing, where the majority of cases have occurred, were swiftly closed as a precautionary public health measure. Our objective was to quantify the impact of LPM closure in reducing bird-to-human transmission of avian influenza A(H7N9) virus. Methods We used data on the illness onset dates and geographical locations of laboratory-confirmed influenza A(H7N9) cases that were officially announced by 7 June 2013. We constructed a statistical model to explain the patterns in incident cases reported in each city based on the assumption of a constant force of infection prior to closure, and a different constant force of infection after closure. We fitted the model using Markov chain Monte Carlo methods. Findings There were 85 confirmed influenza A(H7N9) cases in Shanghai, Hangzhou, Huzhou and Nanjing out of a total of 130 confirmed cases in mainland China by 7 June 2013. Closure of LPMs in those four cities reduced the risk of human infections by 97%–99% (range 68%–100%) in each city. Given that LPMs were the predominant source of influenza A(H7N9) exposure in those locations, we estimated the mean incubation period to be 3.3 days. Interpretation LPM closures were extremely effective in controlling human risk of influenza A(H7N9). If the influenza A(H7N9) epizootic/epidemic continues, LPM closure should be sustained in at-risk areas and implemented in any urban areas where influenza A(H7N9) reappears in future. In the longer term, evidence-based discussions and deliberations about the role of central slaughtering of all live poultry should be renewed. Funding Ministry of Science and Technology, China; Research Fund for the Control of Infectious Disease and University Grants Committee, Hong Kong Special

  11. Practical aspects of vaccination of poultry against avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although little has changed in vaccine technology for avian influenza virus (AIV) in the past 20 years, the approach to vaccination of poultry (chickens, turkeys and ducks) for avian influenza has evolved as highly pathogenic (HP) AIV has become endemic in several regions of the world. Vaccination f...

  12. Pathogenesis and pathobiology of avian influenza virus infection in birds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian Influenza (AI) viruses vary in their ability to produce infection, disease and death in different bird species. Based on the pathobiological features in chickens, AI viruses are categorized as, low (LP) and high pathogenicity (HP). Typically, LPAI (low pathogenicity avian influenza) viruses ...

  13. Experimental vaccinations for avian influenza virus including DIVA approaches

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is a viral disease of poultry that remains an economic threat to commercial poultry throughout the world by negatively impacting animal health and trade. Strategies to control avian influenza (AI) virus are developed to prevent, manage or eradicate the virus from the country, re...

  14. Vaccine induced protection from egg production losses in commercial turkey breeder hens following experimental challenge with a triple reassortant H3N2 avian influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) infection in turkey breeder hens can cause decreases in both egg production and quality which results in significant production losses. Recently, an H3N2 subtype of avian influenza triple reassortant containing human, swine, and avian gene segments was isolated from turkey bree...

  15. New USDA licensed avian influenza vaccine (rHVT-AI) for protection against H5 avian influenza and usage discussion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, a new avian influenza vaccine was licensed by USDA for use in the United States for protection of commercial poultry. The vaccine is a recombinant herpes virus of turkeys expressing the hemagglutinin gene of an H5 subtype avian influenza virus belonging to the 2.2 clade of the H5N1 highly ...

  16. Systems-Level Comparison of Host-Responses Elicited by Avian H5N1 and Seasonal H1N1 Influenza Viruses in Primary Human Macrophages

    PubMed Central

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

    2009-01-01

    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)-α genes. A network-based analysis suggests that the synergy between IFN-β and TNF-α 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. PMID:20011590

  17. Sialic acid receptor specificity on erythrocytes affects detection of antibody to avian influenza haemagglutinin.

    PubMed

    Stephenson, I; Wood, J M; Nicholson, K G; Zambon, M C

    2003-07-01

    Haemagglutination-inhibition tests (HI) are used to detect increases in influenza antibody in serum. However, they are relatively insensitive for the detection of human antibody responses to avian haemagglutinin, even in the presence of high titres of neutralising antibody after confirmed infection or vaccination. Human influenza viruses bind preferentially sialic acid containing N-acetylneuraminic acid alpha2,6-galactose (SAalpha2,6Gal) linkages while avian and equine viruses bind preferentially those containing N-acetylneuraminic acid alpha2,3-galactose (SAalpha2,3Gal) linkages. Increasing the proportion of SAalpha2,3Gal linkages on the erythrocytes used, by enzymatic modification or change of species, improves the ability of erythrocytes to bind to avian influenza strains and thereby improves the sensitivity of detection of antibody to avian and equine HA in a range of mammalian and human sera using HI tests. PMID:12767002

  18. Early Indicators of Disease in Ferrets Infected with a High Dose of Avian Influenza H5N1

    PubMed Central

    Long, James P.; Vela, Eric M.; Stark, Gregory V.; Jones, Kelly J.; Miller, Stephen T.; Bigger, John E.

    2012-01-01

    Avian influenza viruses are widespread in birds, contagious in humans, and are categorized as low pathogenicity avian influenza or highly pathogenic avian influenza. Ferrets are susceptible to infection with avian and human influenza A and B viruses and have been widely used as a model to study pathogenicity and vaccine efficacy. In this report, the natural history of the H5N1 influenza virus A/Vietnam/1203/04 influenza infection in ferrets was examined to determine clinical and laboratory parameters that may indicate (1) the onset of disease and (2) survival. In all, twenty of 24 animals infected with 7 × 105 TCID50 of A/Vietnam/1203/04 succumbed. A statistical analysis identified a combination of parameters including weight loss, nasal wash TCID50, eosinophils, and liver enzymes such as alanine amino transferase that might possibly serve as indicators of both disease onset and challenge survival. PMID:23240077

  19. Novel avian influenza A (H5N6) viruses isolated in migratory waterfowl before the first human case reported in China, 2014

    PubMed Central

    Bi, Yuhai; Liu, Haizhou; Xiong, Chaochao; Di Liu; Shi, Weifeng; Li, Mingxin; Liu, Siling; Chen, Jing; Chen, Guang; Li, Yong; Yang, Guoxiang; Lei, Yongsong; Xiong, Yanping; Lei, Fumin; Wang, Hanzhong; Chen, Quanjiao; Chen, Jianjun; Gao, George F.

    2016-01-01

    In May 2014, China formally confirmed the first human infection with the novel H5N6 avian influenza virus (AIV) in Sichuan Province. Before the first human case was reported, surveillance of AIVs in wild birds resulted in the detection of three H5N6 viruses in faecal samples from migratory waterfowl in Chenhu wetlands, Hubei Province, China. Genetic and phylogenetic analyses revealed that these three novel viruses were closely related to the H5N6 virus that has caused human infections in China since 2014. A Bayesian phylogenetic reconstruction of all eight segments suggests multiple reassortment events in the evolution of these viruses. The hemagglutinin (HA) and neuraminidase (NA) originated from the H5N2 and H6N6 AIVs, respectively, whereas all six internal genes were derived from avian H5N1 viruses. The reassortant may have occurred in eastern China during 2012–2013. A phylogeographic analysis of the HA and NA genes traced the viruses to southern China, from where they spread to other areas via eastern China. A receptor-binding test showed that H5N6 viruses from migratory waterfowl had human-type receptor-binding activity, suggesting a potential for transmission to humans. These data suggest that migratory waterfowl may play a role in the dissemination of novel H5N6 viruses. PMID:27431568

  20. Novel avian influenza A (H5N6) viruses isolated in migratory waterfowl before the first human case reported in China, 2014.

    PubMed

    Bi, Yuhai; Liu, Haizhou; Xiong, Chaochao; Di Liu; Shi, Weifeng; Li, Mingxin; Liu, Siling; Chen, Jing; Chen, Guang; Li, Yong; Yang, Guoxiang; Lei, Yongsong; Xiong, Yanping; Lei, Fumin; Wang, Hanzhong; Chen, Quanjiao; Chen, Jianjun; Gao, George F

    2016-01-01

    In May 2014, China formally confirmed the first human infection with the novel H5N6 avian influenza virus (AIV) in Sichuan Province. Before the first human case was reported, surveillance of AIVs in wild birds resulted in the detection of three H5N6 viruses in faecal samples from migratory waterfowl in Chenhu wetlands, Hubei Province, China. Genetic and phylogenetic analyses revealed that these three novel viruses were closely related to the H5N6 virus that has caused human infections in China since 2014. A Bayesian phylogenetic reconstruction of all eight segments suggests multiple reassortment events in the evolution of these viruses. The hemagglutinin (HA) and neuraminidase (NA) originated from the H5N2 and H6N6 AIVs, respectively, whereas all six internal genes were derived from avian H5N1 viruses. The reassortant may have occurred in eastern China during 2012-2013. A phylogeographic analysis of the HA and NA genes traced the viruses to southern China, from where they spread to other areas via eastern China. A receptor-binding test showed that H5N6 viruses from migratory waterfowl had human-type receptor-binding activity, suggesting a potential for transmission to humans. These data suggest that migratory waterfowl may play a role in the dissemination of novel H5N6 viruses. PMID:27431568

  1. Avian Influenza Viruses, Inflammation, and CD8(+) T Cell Immunity.

    PubMed

    Wang, Zhongfang; Loh, Liyen; Kedzierski, Lukasz; Kedzierska, Katherine

    2016-01-01

    Avian influenza viruses (AIVs) circulate naturally in wild aquatic birds, infect domestic poultry, and are capable of causing sporadic bird-to-human transmissions. AIVs capable of infecting humans include a highly pathogenic AIV H5N1, first detected in humans in 1997, and a low pathogenic AIV H7N9, reported in humans in 2013. Both H5N1 and H7N9 cause severe influenza disease in humans, manifested by acute respiratory distress syndrome, multi-organ failure, and high mortality rates of 60% and 35%, respectively. Ongoing circulation of H5N1 and H7N9 viruses in wild birds and poultry, and their ability to infect humans emphasizes their epidemic and pandemic potential and poses a public health threat. It is, thus, imperative to understand the host immune responses to the AIVs so we can control severe influenza disease caused by H5N1 or H7N9 and rationally design new immunotherapies and vaccines. This review summarizes our current knowledge on AIV epidemiology, disease symptoms, inflammatory processes underlying the AIV infection in humans, and recent studies on universal pre-existing CD8(+) T cell immunity to AIVs. Immune responses driving the host recovery from AIV infection in patients hospitalized with severe influenza disease are also discussed. PMID:26973644

  2. Avian Influenza Viruses, Inflammation, and CD8+ T Cell Immunity

    PubMed Central

    Wang, Zhongfang; Loh, Liyen; Kedzierski, Lukasz; Kedzierska, Katherine

    2016-01-01

    Avian influenza viruses (AIVs) circulate naturally in wild aquatic birds, infect domestic poultry, and are capable of causing sporadic bird-to-human transmissions. AIVs capable of infecting humans include a highly pathogenic AIV H5N1, first detected in humans in 1997, and a low pathogenic AIV H7N9, reported in humans in 2013. Both H5N1 and H7N9 cause severe influenza disease in humans, manifested by acute respiratory distress syndrome, multi-organ failure, and high mortality rates of 60% and 35%, respectively. Ongoing circulation of H5N1 and H7N9 viruses in wild birds and poultry, and their ability to infect humans emphasizes their epidemic and pandemic potential and poses a public health threat. It is, thus, imperative to understand the host immune responses to the AIVs so we can control severe influenza disease caused by H5N1 or H7N9 and rationally design new immunotherapies and vaccines. This review summarizes our current knowledge on AIV epidemiology, disease symptoms, inflammatory processes underlying the AIV infection in humans, and recent studies on universal pre-existing CD8+ T cell immunity to AIVs. Immune responses driving the host recovery from AIV infection in patients hospitalized with severe influenza disease are also discussed. PMID:26973644

  3. Emerging Infections of CNS: Avian Influenza A, Rift Valley Fever and Human Parecho Viruses

    PubMed Central

    Wiley, Clayton A.; Bhardwaj, Nitin; Ross, Ted M.; Bissel, Stephanie J.

    2015-01-01

    History is replete with emergent pandemic infections that have decimated the human population. Given the shear mass of humans that now crowd the earth, there is every reason to suspect history will repeat itself. We describe three RNA viruses that have recently emerged in the human population to mediate severe neurological disease. These new diseases are results of new mutations in the infectious agents or new exposure pathways to the agents or both. To appreciate their pathogenesis, we summarize the essential virology and immune response to each agent. Infection is described in the context of known host defenses. Once the viruses evade immune defenses and enter CNS cells, they rapidly co-opt host RNA processing to a cataclysmic extent. It is not clear why the brain is particularly susceptible to RNA viruses; but perhaps because of its tremendous dependence on RNA processing for physiological functioning, classical mechanisms of host defense (e.g. interferon disruption of viral replication) are diminished or not available. Effectiveness of immunity, immunization and pharmacological therapies is reviewed to contextualize the scope of the public health challenge. Unfortunately, vaccines that confer protection from systemic disease do not necessarily confer protection for the brain after exposure through unconventional routes. PMID:26276027

  4. IDENTIFYING AREAS WITH A HIGH RISK OF HUMAN INFECTION WITH THE AVIAN INFLUENZA A (H7N9) VIRUS IN EAST ASIA

    PubMed Central

    Fuller, Trevon; Havers, Fiona; Xu, Cuiling; Fang, Li-Qun; Cao, Wu-Chun; Shu, Yuelong; Widdowson, Marc-Alain; Smith, Thomas B.

    2014-01-01

    Summary Objectives The rapid emergence, spread, and disease severity of avian influenza A(H7N9) in China has prompted concerns about a possible pandemic and regional spread in the coming months. The objective of this study was to predict the risk of future human infections with H7N9 in China and neighboring countries by assessing the association between H7N9 cases at sentinel hospitals and putative agricultural, climatic, and demographic risk factors. Methods This cross-sectional study used the locations of H7N9 cases and negative cases from China’s influenza-like illness surveillance network. After identifying H7N9 risk factors with logistic regression, we used Geographic Information Systems (GIS) to construct predictive maps of H7N9 risk across Asia. Results Live bird market density was associated with human H7N9 infections reported in China from March-May 2013. Based on these cases, our model accurately predicted the virus’ spread into Guangxi autonomous region in February 2014. Outside China, we find there is a high risk that the virus will spread to northern Vietnam, due to the import of poultry from China. Conclusions Our risk map can focus efforts to improve surveillance in poultry and humans, which may facilitate early identification and treatment of human cases. PMID:24642206

  5. Pro-inflammatory cytokine dysregulation is associated with novel avian influenza A (H7N9) virus in primary human macrophages.

    PubMed

    Zhao, Chihao; Qi, Xian; Ding, Meng; Sun, Xinlei; Zhou, Zhen; Zhang, Shuo; Zen, Ke; Li, Xihan

    2016-02-01

    Since March 2013, more than 500 laboratory-confirmed human H7N9 influenza A virus infection cases have been recorded, with a case fatality rate of more than 30%. Clinical research has shown that cytokine and chemokine dysregulation contributes to the pathogenicity of the H7N9 virus. Here, we investigated cytokine profiles in primary human macrophages infected with the novel H7N9 virus, using cytokine antibody arrays. The levels of several pro-inflammatory cytokines, particularly TNF-α, were increased in H7N9-infected macrophages. Induction of the transcriptional and translational levels of the pro-inflammatory cytokines by H7N9 virus seemed to be intermediate between those induced by highly pathogenic avian H5N1 and pandemic human H1N1 viruses, which were detected by ELISA and real-time quantitative PCR, respectively. Additionally, compared with H5N1, the upregulation of pro-inflammatory cytokines caused by H7N9 infection occurred rapidly but mildly. Our results identified the overall profiles of cytokine and chemokine induction by the H7N9 influenza virus in an in vitro cell-culture model, and could provide potential therapeutic targets for the control of severe human H7N9 disease. PMID:26644088

  6. Differences in the epidemiology and virology of mild, severe and fatal human infections with avian influenza A (H7N9) virus.

    PubMed

    Sha, Jianping; Chen, Xiaowen; Ren, Yajin; Chen, Haijun; Wu, Zuqun; Ying, Dong; Zhang, Zhiruo; Liu, Shelan

    2016-05-01

    A novel avian influenza A (H7N9) virus caused 5-10 % mild and 30.5 % fatal human infections as of December 10, 2015. In order to investigate the reason for the higher rate of fatal outcome of this infection, this study compared the molecular epidemiology and virology of avian influenza A (H7N9) viruses from mild (N = 14), severe (N = 50) and fatal (N = 35) cases, as well as from non-human hosts (N = 73). The epidemiological results showed that the average age of the people in the mild, severe and fatal groups was 27.6, 52 and 62 years old, respectively (p < 0.001). Males accounted for 42.9 % (6/14), 58.0 % (29/50), and 74.3 % (26/35) of cases in the mild, severe and fatal group respectively (p = 0.094). Median days from onset to start of antiviral treatment were 2, 5 and 7 days in the mild, severe and fatal group, respectively (p = 0.002). The median time from onset to discharge/death was 12, 40 and 19 days in the mild, severe and fatal group, respectively (p < 0.001). Analysis of whole genome sequences showed that PB2 (E627K), NA (R294K) and PA (V100A) mutations were markedly associated with an increased fatality rate, while HA (N276D) and PB2 (N559T) mutations were clearly related to mild cases. There were no differences in the genotypes, adaptation to mammalian hosts, and genetic identity between the three types of infection. In conclusion, advanced age and delayed confirmation of diagnosis and antiviral intervention were risk factors for death. Furthermore, PB2 (E627K), NA (R294K) and PA (V100A) mutations might contribute to a fatal outcome in human H7N9 infection. PMID:26887968

  7. USGS role and response to highly pathogenic avian influenza

    USGS Publications Warehouse

    Harris, M. Camille; Miles, A. Keith; Pearce, John M.; Prosser, Diann J.; Sleeman, Jonathan M.; Whalen, Mary E.

    2015-01-01

    Avian influenza viruses are naturally occurring in wild birds such as ducks, geese, swans, and gulls. These viruses generally do not cause illness in wild birds, however, when spread to poultry they can be highly pathogenic and cause illness and death in backyard and commercial farms. Outbreaks may cause devastating agricultural economic losses and some viral strains have the potential to infect people directly. Furthermore, the combination of avian influenza viruses with mammalian viruses can result in strains with the ability to transmit from person to person, possibly leading to viruses with pandemic potential. All known pandemic influenza viruses have had some genetic material of avian origin. Since 1996, a strain of highly pathogenic avian influenza (HPAI) virus, H5N1, has caused infection in wild birds, losses to poultry farms in Eurasia and North Africa, and led to the deaths of several hundred people. Spread of the H5N1 virus and other influenza strains from China was likely facilitated by migratory birds. In December 2014, HPAI was detected in poultry in Canada and migratory birds in the United States. Since then, HPAI viruses have spread to large parts of the United States and will likely continue to spread through migratory bird flyways and other mechanisms throughout North America. In the United States, HPAI viruses have severely affected the poultry industry with millions of domestic birds dead or culled. These strains of HPAI are not known to cause disease in humans; however, the Centers for Disease Control and Prevention (CDC) advise caution when in close contact with infected birds. Experts agree that HPAI strains currently circulating in wild birds of North America will likely persist for the next few years. This unprecedented situation presents risks to the poultry industry, natural resource management, and potentially human health. Scientific knowledge and decision support tools are urgently needed to understand factors affecting the persistence

  8. Case-control study of risk factors for human infection with avian influenza A(H7N9) virus in Shanghai, China, 2013.

    PubMed

    Li, J; Chen, J; Yang, G; Zheng, Y X; Mao, S H; Zhu, W P; Yu, X L; Gao, Y; Pan, Q C; Yuan, Z A

    2015-07-01

    The first human infection with avian influenza A(H7N9) virus was reported in Shanghai, China in March 2013. An additional 32 cases of human H7N9 infection were identified in the following months from March to April 2013 in Shanghai. Here we conducted a case-control study of the patients with H7N9 infection (n = 25) using controls matched by age, sex, and residence to determine risk factors for H7N9 infection. Our findings suggest that chronic disease and frequency of visiting a live poultry market (>10 times, or 1-9 times during the 2 weeks before illness onset) were likely to be significantly associated with H7N9 infection, with the odds ratios being 4.07 [95% confidence interval (CI) 1.32-12.56], 10.61 (95% CI 1.85-60.74), and 3.76 (95% CI 1.31-10.79), respectively. Effective strategies for live poultry market control should be reinforced and ongoing education of the public is warranted to promote behavioural changes that can help to eliminate direct or indirect contact with influenza A(H7N9) virus. PMID:25471822

  9. A confirmed severe case of human infection with avian-origin influenza H7N9: A case report

    PubMed Central

    CAO, HUI-FANG; LIANG, ZHONG-HUI; FENG, YING; ZHANG, ZI-NAN; XU, JING; HE, HE

    2015-01-01

    A male patient, aged 77 years, was admitted to hospital with the chief complaint of persistent hyperpyrexia that had presented for four days. The patient also suffered from hypoxemia, and a large white shadow in the left lung was observed on a chest radiograph, indicating inflammation. No therapeutic effect was observed with anti-infection treatment. The patient admitted a history of direct contact with live chickens two weeks prior to hospital admission. The day after admission to the Jingnan District Centre Hospital of Shanghai (Shanghai, China), the patient was diagnosed with severe H7N9 avian influenza infection by nasopharyngeal swab and blood sampling detection. Although the patient received anti-infective drugs, intubated assisted ventilation and circulation support, the condition of the patient continued to rapidly deteriorate. Oxygen saturation decreased and gastrointestinal bleeding occurred, with the body temperature fluctuating between 39 and 40°C. By day 6 after admission, the patient presented with circulatory failure, with liver and renal failure. On day 7, the blood pressure of the patient was unable to be measured, and the patient was diagnosed with multiple organ dysfunction. Subsequently, clinical death was declared with the patient exhibiting asystole and no spontaneous breathing. PMID:25667615

  10. Characterizing Loop Dynamics and Ligand Recognition in Human- and Avian-Type Influenza Neuraminidases via Generalized Born Molecular Dynamics and End-Point Free Energy Calculations

    SciTech Connect

    Amaro, Rommie E; Cheng, Xiaolin; Ivanov, Ivaylo N; Xu, Dong; McCammon, Jonathan

    2009-01-01

    The comparative dynamics and inhibitor binding free energies of group-1 and group-2 pathogenic influenza A subtype neuraminidase (NA) enzymes are of fundamental biological interest and relevant to structure-based drug design studies for antiviral compounds. In this work, we present seven generalized Born molecular dynamics simulations of avian (N1)- and human (N9)-type NAs in order to probe the comparative flexibility of the two subtypes, both with and without the inhibitor oseltamivir bound. The enhanced sampling obtained through the implicit solvent treatment suggests several provocative insights into the dynamics of the two subtypes, including that the group-2 enzymes may exhibit similar motion in the 430-binding site regions but different 150-loop motion. End-point free energy calculations elucidate the contributions to inhibitor binding free energies and suggest that entropic considerations cannot be neglected when comparing across the subtypes. We anticipate the findings presented here will have broad implications for the development of novel antiviral compounds against both seasonal and pandemic influenza strains.

  11. Serologic cross reactivity of avian influenza H1 vaccinated commercial U.S. turkeys to the emergent H1N1 influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, the 2009 human H1N1 influenza virus was identified in turkey breeders in Chile, Canada and the U.S. resulting in infection and production losses. In these studies sera from turkeys vaccinated against avian influenza H1 were tested against the recent human pandemic H1N1 virus. Genetic ana...

  12. Avian Influenza Virus Infection of Immortalized Human Respiratory Epithelial Cells Depends upon a Delicate Balance between Hemagglutinin Acid Stability and Endosomal pH.

    PubMed

    Daidoji, Tomo; Watanabe, Yohei; Ibrahim, Madiha S; Yasugi, Mayo; Maruyama, Hisataka; Masuda, Taisuke; Arai, Fumihito; Ohba, Tomoyuki; Honda, Ayae; Ikuta, Kazuyoshi; Nakaya, Takaaki

    2015-04-24

    The highly pathogenic avian influenza (AI) virus, H5N1, is a serious threat to public health worldwide. Both the currently circulating H5N1 and previously circulating AI viruses recognize avian-type receptors; however, only the H5N1 is highly infectious and virulent in humans. The mechanism(s) underlying this difference in infectivity remains unclear. The aim of this study was to clarify the mechanisms responsible for the difference in infectivity between the current and previously circulating strains. Primary human small airway epithelial cells (SAECs) were transformed with the SV40 large T-antigen to establish a series of clones (SAEC-Ts). These clones were then used to test the infectivity of AI strains. Human SAEC-Ts could be broadly categorized into two different types based on their susceptibility (high or low) to the viruses. SAEC-T clones were poorly susceptible to previously circulating AI but were completely susceptible to the currently circulating H5N1. The hemagglutinin (HA) of the current H5N1 virus showed greater membrane fusion activity at higher pH levels than that of previous AI viruses, resulting in broader cell tropism. Moreover, the endosomal pH was lower in high susceptibility SAEC-T clones than that in low susceptibility SAEC-T clones. Taken together, the results of this study suggest that the infectivity of AI viruses, including H5N1, depends upon a delicate balance between the acid sensitivity of the viral HA and the pH within the endosomes of the target cell. Thus, one of the mechanisms underlying H5N1 pathogenesis in humans relies on its ability to fuse efficiently with the endosomes in human airway epithelial cells. PMID:25673693

  13. Rapid diagnostics for avian influenza -- Advances in testing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A variety of tools are available for the diagnosis of avian influenza virus. They can be generally divided into the serologic diagnostic tests and direct virus detection tests. The serologic tests are important primarily for active surveillance to assure our poultry flocks are free of avian influe...

  14. Design of Multiplexed Detection Assays for Identification of Avian Influenza A Virus Subtypes Pathogenic to Humans by SmartCycler Real-Time Reverse Transcription-PCR ▿

    PubMed Central

    Wang, Wei; Ren, Peijun; Mardi, Sek; Hou, Lili; Tsai, Cheguo; Chan, Kwok Hung; Cheng, Peter; Sheng, Jun; Buchy, Philippe; Sun, Bing; Toyoda, Tetsuya; Lim, Wilina; Peiris, J. S. Malik; Zhou, Paul; Deubel, Vincent

    2009-01-01

    Influenza A virus (IAV) epidemics are the result of human-to-human or poultry-to-human transmission. Tracking seasonal outbreaks of IAV and other avian influenza virus (AIV) subtypes that can infect humans, aquatic and migratory birds, poultry, and pigs is essential for epidemiological surveillance and outbreak alerts. In this study, we performed four real-time reverse transcription-PCR (rRT-PCR) assays for identification of the IAV M and hemagglutinin (HA) genes from six known AIVs infecting pigs, birds, and humans. IAV M1 gene-positive samples tested by single-step rRT-PCR and a fluorogenic Sybr green I detection system were further processed for H5 subtype identification by using two-primer-set multiplex and Sybr green I rRT-PCR assays. H5 subtype-negative samples were then tested with either a TaqMan assay for subtypes H1 and H3 or a TaqMan assay for subtypes H2, H7, and H9 and a beacon multiplex rRT-PCR identification assay. The four-tube strategy was able to detect 10 RNA copies of the HA genes of subtypes H1, H2, H3, H5, and H7 and 100 RNA copies of the HA gene of subtype H9. At least six H5 clades of H5N1 viruses isolated in Southeast Asia and China were detected by that test. Using rRT-PCR assays for the M1 and HA genes in 202 nasopharyngeal swab specimens from children with acute respiratory infections, we identified a total of 39 samples positive for the IAV M1 gene and subtypes H1 and H3. When performed with a portable SmartCycler instrument, the assays offer an efficient, flexible, and reliable platform for investigations of IAV and AIV in remote hospitals and in the field. PMID:18971359

  15. Avian Influenza spread and transmission dynamics

    USGS Publications Warehouse

    Bourouiba, Lydia; Gourley, Stephen A.; Liu, Rongsong; Takekawa, John Y.; Wu, Jianhong

    2015-01-01

    The spread of highly pathogenic avian influenza (HPAI) viruses of type A of subtype H5N1 has been a serious threat to global public health. Understanding the roles of various (migratory, wild, poultry) bird species in the transmission of these viruses is critical for designing and implementing effective control and intervention measures. Developing appropriate models and mathematical techniques to understand these roles and to evaluate the effectiveness of mitigation strategies have been a challenge. Recent development of the global health surveillance (especially satellite tracking and GIS techniques) and the mathematical theory of dynamical systems combined have gradually shown the promise of some cutting-edge methodologies and techniques in mathematical biology to meet this challenge.

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

    PubMed

    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

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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...

  18. Efficacy of inactivated influenza vaccines for protection of poultry against the H7N9 low pathogenic avian influenza virus isolated in China during 2013

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recent outbreak in China of avian influenza (AI) H7N9 in birds and humans underscores the interspecies movement of these viruses. Interestingly, the genetic composition of these H7N9 viruses appears to be solely of avian origin and of low pathogenicity in birds. Although few isolations of these ...

  19. Generation of Influenza Virus from Avian Cells Infected by Salmonella Carrying the Viral Genome

    PubMed Central

    Zhang, Xiangmin; Kong, Wei; Wanda, Soo-Young; Xin, Wei; Alamuri, Praveen; Curtiss, Roy

    2015-01-01

    Domestic poultry serve as intermediates for transmission of influenza A virus from the wild aquatic bird reservoir to humans, resulting in influenza outbreaks in poultry and potential epidemics/pandemics among human beings. To combat emerging avian influenza virus, an inexpensive, heat-stable, and orally administered influenza vaccine would be useful to vaccinate large commercial poultry flocks and even migratory birds. Our hypothesized vaccine is a recombinant attenuated bacterial strain able to mediate production of attenuated influenza virus in vivo to induce protective immunity against influenza. Here we report the feasibility and technical limitations toward such an ideal vaccine based on our exploratory study. Five 8-unit plasmids carrying a chloramphenicol resistance gene or free of an antibiotic resistance marker were constructed. Influenza virus was successfully generated in avian cells transfected by each of the plasmids. The Salmonella carrier was engineered to allow stable maintenance and conditional release of the 8-unit plasmid into the avian cells for recovery of influenza virus. Influenza A virus up to 107 50% tissue culture infective doses (TCID50)/ml were recovered from 11 out of 26 co-cultures of chicken embryonic fibroblasts (CEF) and Madin-Darby canine kidney (MDCK) cells upon infection by the recombinant Salmonella carrying the 8-unit plasmid. Our data prove that a bacterial carrier can mediate generation of influenza virus by delivering its DNA cargoes into permissive host cells. Although we have made progress in developing this Salmonella influenza virus vaccine delivery system, further improvements are necessary to achieve efficient virus production, especially in vivo. PMID:25742162

  20. A Complete Molecular Diagnostic Procedure for Applications in Surveillance and Subtyping of Avian Influenza Virus

    PubMed Central

    Tseng, Chun-Hsien; Tsai, Hsiang-Jung; Chang, Chung-Ming

    2014-01-01

    Introduction. The following complete molecular diagnostic procedure we developed, based on real-time quantitative PCR and traditional PCR, is effective for avian influenza surveillance, virus subtyping, and viral genome sequencing. Method. This study provides a specific and sensitive step-by-step procedure for efficient avian influenza identification of 16 hemagglutinin and 9 neuraminidase avian influenza subtypes. Result and Conclusion. This diagnostic procedure may prove exceedingly useful for virological and ecological advancements in global avian influenza research. PMID:25057497

  1. Avian influenza viruses and avian paramyxoviruses in wintering and breeding waterfowl populations in North Carolina, USA

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Although wild ducks are recognized reservoirs for avian influenza (AIV) and avian paramyxoviruses (APMV), information related to the prevalence of these viruses in breeding and migratory duck populations on North American wintering grounds is limited. Wintering (n=2,889) and resident breeding (n=524...

  2. Serologic cross reactivity of serum samples from avian influenza vaccinated commercial U.S. turkeys to the emergent H1N1 influenza virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Recently, the 2009 human H1N1 influenza virus was identified in turkey breeders in Chile and Canada resulting in infection and egg production losses. In the U.S., vaccination of turkeys against avian influenza may include H1 and H3 viruses also isolated from swine. We tested whether sera from turk...

  3. Inhibiting avian influenza virus shedding using a novel RNAi antiviral vector technology: proof of concept in an avian cell model.

    PubMed

    Linke, Lyndsey M; Wilusz, Jeffrey; Pabilonia, Kristy L; Fruehauf, Johannes; Magnuson, Roberta; Olea-Popelka, Francisco; Triantis, Joni; Landolt, Gabriele; Salman, Mo

    2016-03-01

    Influenza A viruses pose significant health and economic threats to humans and animals. Outbreaks of avian influenza virus (AIV) are a liability to the poultry industry and increase the risk for transmission to humans. There are limitations to using the AIV vaccine in poultry, creating barriers to controlling outbreaks and a need for alternative effective control measures. Application of RNA interference (RNAi) techniques hold potential; however, the delivery of RNAi-mediating agents is a well-known obstacle to harnessing its clinical application. We introduce a novel antiviral approach using bacterial vectors that target avian mucosal epithelial cells and deliver (small interfering RNA) siRNAs against two AIV genes, nucleoprotein (NP) and polymerase acidic protein (PA). Using a red fluorescent reporter, we first demonstrated vector delivery and intracellular expression in avian epithelial cells. Subsequently, we demonstrated significant reductions in AIV shedding when applying these anti-AIV vectors prophylactically. These antiviral vectors provided up to a 10,000-fold reduction in viral titers shed, demonstrating in vitro proof-of-concept for using these novel anti-AIV vectors to inhibit AIV shedding. Our results indicate this siRNA vector technology could represent a scalable and clinically applicable antiviral technology for avian and human influenza and a prototype for RNAi-based vectors against other viruses. PMID:26910902

  4. Susceptibility of avian species to north american H13 low pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gulls are widely recognized reservoirs for low pathogenic avian influenza (LPAI) viruses; however, the subtypes maintained in these populations and/or the transmission mechanisms involved are poorly understood. Although, a wide diversity of influenza viruses have been isolated from gulls, two hemag...

  5. Comparative susceptibility of avian species to low pathogenic avian influenza viruses of the H13 subtype

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Gulls are widely recognized reservoirs for low pathogenic avian influenza (LPAI) viruses; however, the subtypes maintained in these populations and/or the transmission mechanisms involved are poorly understood. Although, a wide diversity of influenza viruses have been isolated from gulls, two hemag...

  6. In ovo and in vitro susceptibility of American alligators (Alligator mississippiensis) to avian influenza virus infection.

    PubMed

    Temple, Bradley L; Finger, John W; Jones, Cheryl A; Gabbard, Jon D; Jelesijevic, Tomislav; Uhl, Elizabeth W; Hogan, Robert J; Glenn, Travis C; Tompkins, S Mark

    2015-01-01

    Avian influenza has emerged as one of the most ubiquitous viruses within our biosphere. Wild aquatic birds are believed to be the primary reservoir of all influenza viruses; however, the spillover of H5N1 highly pathogenic avian influenza (HPAI) and the recent swine-origin pandemic H1N1 viruses have sparked increased interest in identifying and understanding which and how many species can be infected. Moreover, novel influenza virus sequences were recently isolated from New World bats. Crocodilians have a slow rate of molecular evolution and are the sister group to birds; thus they are a logical reptilian group to explore susceptibility to influenza virus infection and they provide a link between birds and mammals. A primary American alligator (Alligator mississippiensis) cell line, and embryos, were infected with four, low pathogenic avian influenza (LPAI) strains to assess susceptibility to infection. Embryonated alligator eggs supported virus replication, as evidenced by the influenza virus M gene and infectious virus detected in allantoic fluid and by virus antigen staining in embryo tissues. Primary alligator cells were also inoculated with the LPAI viruses and showed susceptibility based upon antigen staining; however, the requirement for trypsin to support replication in cell culture limited replication. To assess influenza virus replication in culture, primary alligator cells were inoculated with H1N1 human influenza or H5N1 HPAI viruses that replicate independent of trypsin. Both viruses replicated efficiently in culture, even at the 30 C temperature preferred by the alligator cells. This research demonstrates the ability of wild-type influenza viruses to infect and replicate within two crocodilian substrates and suggests the need for further research to assess crocodilians as a species potentially susceptible to influenza virus infection. PMID:25380354

  7. Little Evidence of Subclinical Avian Influenza Virus Infections among Rural Villagers in Cambodia

    PubMed Central

    Gray, Gregory C.; Krueger, Whitney S.; Chum, Channimol; Putnam, Shannon D.; Wierzba, Thomas F.; Heil, Gary L.; Anderson, Benjamin D.; Yasuda, Chadwick Y.; Williams, Maya; Kasper, Matthew R.; Saphonn, Vonthanak; Blair, Patrick J.

    2014-01-01

    In 2008, 800 adults living within rural Kampong Cham Province, Cambodia were enrolled in a prospective cohort study of zoonotic influenza transmission. After enrollment, participants were contacted weekly for 24 months to identify acute influenza-like illnesses (ILI). Follow-up sera were collected at 12 and 24 months. A transmission substudy was also conducted among the family contacts of cohort members reporting ILI who were influenza A positive. Samples were assessed using serological or molecular techniques looking for evidence of infection with human and avian influenza viruses. Over 24 months, 438 ILI investigations among 284 cohort members were conducted. One cohort member was hospitalized with a H5N1 highly pathogenic avian influenza (HPAI) virus infection and withdrew from the study. Ninety-seven ILI cases (22.1%) were identified as influenza A virus infections by real-time RT-PCR; none yielded evidence for AIV. During the 2 years of follow-up, 21 participants (3.0%) had detectable antibody titers (≥1∶10) against the studied AIVs: 1 against an avian-like A/Migratory duck/Hong Kong/MPS180/2003(H4N6), 3 against an avian-like A/Teal/Hong Kong/w312/97(H6N1), 9 (3 of which had detectible antibody titers at both 12- and 24-month follow-up) against an avian-like A/Hong Kong/1073/1999(H9N2), 6 (1 detected at both 12- and 24-month follow-up) against an avian-like A/Duck/Memphis/546/74(H11N9), and 2 against an avian-like A/Duck/Alberta/60/76(H12N5). With the exception of the one hospitalized cohort member with H5N1 infection, no other symptomatic avian influenza infections were detected among the cohort. Serological evidence for subclinical infections was sparse with only one subject showing a 4-fold rise in microneutralization titer over time against AvH12N5. In summary, despite conducting this closely monitored cohort study in a region enzootic for H5N1 HPAI, we were unable to detect subclinical avian influenza infections, suggesting either that these

  8. Dynamic quantification of avian influenza H7N9(A) virus in a human infection during clinical treatment using droplet digital PCR.

    PubMed

    Yan, Yong; Jia, Xiao-Jun; Wang, Heng-Hui; Fu, Xiao-Fei; Ji, Ji-Mei; He, Pei-Yan; Chen, Li-Xia; Luo, Jian-Yong; Chen, Zhong-Wen

    2016-08-01

    This study involved a human infection with avian influenza H7N9(A) virus in Zhejiang province, the first one after implementing the closure measures of living poultry markets in China. The clinical symptoms, epidemiological and virological characteristics of the case were described briefly, and as the emphasis, H7N9 virus was detected quantitatively and continuously from the collected samples in 10 different periods of the patient's treatment in order to reveal changes of viral load in patient's body during the treatment. This study first used reverse-transcription droplet digital PCR (RT-ddPCR) assays to monitor viral load dynamically for human H7N9 infection, synchronously performing real-time RT-PCR as a reference technology to obtain more comprehensive data for comparison. Our results indicated that RT-ddPCR compared to real-time RT-PCR is more sensitive and accurate for quantifying H7N9 viral load without the use of standard curves. Furthermore it can provide reference data for clinical policies including infectivity judgement, ward transferring and therapy adjustment for the patient during treatment. PMID:27058642

  9. Synergistic Effect of S224P and N383D Substitutions in the PA of H5N1 Avian Influenza Virus Contributes to Mammalian Adaptation

    PubMed Central

    Song, Jiasheng; Xu, Jing; Shi, Jianzhong; Li, Yanbing; Chen, Hualan

    2015-01-01

    The adaptation of H5N1 avian influenza viruses to human poses a great threat to public health. Previous studies indicate the adaptive mutations in viral polymerase of avian influenza viruses are major contributors in overcoming the host species barrier, with the majority of mammalian adaptive mutations occurring in the PB2 protein. However, the adaptive mutations in the PA protein of the H5N1 avian influenza virus are less defined and poorly understood. In this study, we identified the synergistic effect of the PA/224P + 383D of H5N1 avian influenza viruses and its ability to enhance the pathogenicity and viral replication in a mammalian mouse model. Interestingly, the signature of PA/224P + 383D mainly exists in mammalian isolates of the H5N1 influenza virus and pdmH1N1 influenza virus, providing a potential pathway for the natural adaptation to mammals which imply the effects of natural adaptation to mammals. Notably, the mutation of PA/383D, which is highly conserved in avian influenza viruses, increases the polymerase activity in both avian and human cells, and may have roles in maintaining the avian influenza virus in their avian reservoirs, and jumping species to infect humans. PMID:26000865

  10. Highly Pathogenic Avian Influenza H5N1, Thailand, 2004

    PubMed Central

    Chaitaweesub, Prasit; Songserm, Thaweesak; Chaisingh, Arunee; Hoonsuwan, Wirongrong; Buranathai, Chantanee; Parakamawongsa, Tippawon; Premashthira, Sith; Amonsin, Alongkorn; Gilbert, Marius; Nielen, Mirjam; Stegeman, Arjan

    2005-01-01

    In January 2004, highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype was first confirmed in poultry and humans in Thailand. Control measures, e.g., culling poultry flocks, restricting poultry movement, and improving hygiene, were implemented. Poultry populations in 1,417 villages in 60 of 76 provinces were affected in 2004. A total of 83% of infected flocks confirmed by laboratories were backyard chickens (56%) or ducks (27%). Outbreaks were concentrated in the Central, the southern part of the Northern, and Eastern Regions of Thailand, which are wetlands, water reservoirs, and dense poultry areas. More than 62 million birds were either killed by HPAI viruses or culled. H5N1 virus from poultry caused 17 human cases and 12 deaths in Thailand; a number of domestic cats, captive tigers, and leopards also died of the H5N1 virus. In 2005, the epidemic is ongoing in Thailand. PMID:16318716

  11. Erythrocyte binding preference of avian influenza H5N1 viruses.

    PubMed

    Louisirirotchanakul, Suda; Lerdsamran, Hatairat; Wiriyarat, Witthawat; Sangsiriwut, Kantima; Chaichoune, Kridsda; Pooruk, Phisanu; Songserm, Taweesak; Kitphati, Rungrueng; Sawanpanyalert, Pathom; Komoltri, Chulaluk; Auewarakul, Prasert; Puthavathana, Pilaipan

    2007-07-01

    Five erythrocyte species (horse, goose, chicken, guinea pig, and human) were used to agglutinate avian influenza H5N1 viruses by hemagglutination assay and to detect specific antibody by hemagglutination inhibition test. We found that goose erythrocytes confer a greater advantage over other erythrocyte species in both assays. PMID:17522271

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

    Technology Transfer Automated Retrieval System (TEKTRAN)

    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 ...

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

    PubMed

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

    2015-02-01

    Since 1997, human infection with avian H5N1, having about 60% mortality, has posed a threat to public health. In this review, we describe the epidemiology of H5N1 transmission, advantages and disadvantages of different influenza vaccine types, and characteristics of adenovirus, finally summarizing advances in adenovirus-based H5N1 systemic and mucosal vaccines. PMID:25479556

  14. Avian Influenza Biosecurity: Filling the Gaps with Non-Traditional Education

    ERIC Educational Resources Information Center

    Madsen, Jennifer; Tablante, Nathaniel

    2013-01-01

    Outbreaks of highly pathogenic avian influenza have become endemic, crippling trade and livelihood for many, and in rare cases, resulting in human fatalities. It is imperative that up-to-date education and training in accessible and interactive formats be available to key target audiences like poultry producers, backyard flock owners, and…

  15. Global avian influenza surveillance in wild birds: A strategy to capture viral diversity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is a global threat to food animal production and distribution systems as well as human health. However, a sustained, comprehensive and coordinated global effort to monitor the continually changing genetic diversity of AI viruses (AIVs) circulating in nature is lacking. Two strai...

  16. Protection of chickens against avian influenza with non-replicating adenovirus-vectored vaccine

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Protective immunity against avian influenza (AI) virus was elicited in chickens by single-dose vaccination with a replication competent adenovirus (RCA) -free human adenovirus (Ad) vector encoding a H7 hemagglutinin gene from a low pathogenic North American isolate (AdChNY94.H7). Chickens vaccinate...

  17. Airborne transmission of H5N1 high pathogenicity avian influenza viruses during simulated home slaughter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Most H5N1 human infections have occurred following exposure to H5N1 high pathogenicity avian influenza (HPAI) virus-infected poultry, especially when poultry are home slaughtered or slaughtered in live poultry markets. Previous studies have demonstrated that slaughter of clade 1 isolate A/Vietnam/1...

  18. Cross talk between animal and human influenza viruses.

    PubMed

    Ozawa, Makoto; Kawaoka, Yoshihiro

    2013-01-01

    Although outbreaks of highly pathogenic avian influenza in wild and domestic birds have been posing the threat of a new influenza pandemic for the past decade, the first pandemic of the twenty-first century came from swine viruses. This fact emphasizes the complexity of influenza viral ecology and the difficulty of predicting influenza viral dynamics. Complete control of influenza viruses seems impossible. However, we must minimize the impact of animal and human influenza outbreaks by learning lessons from past experiences and recognizing the current status. Here, we review the most recent influenza virology data in the veterinary field, including aspects of zoonotic agents and recent studies that assess the pandemic potential of H5N1 highly pathogenic avian influenza viruses. PMID:25387011

  19. Single assay for simultaneous detection and differential identification of human and avian influenza virus types, subtypes, and emergent variants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rapid and accurate detection, identification and genetic characterization are essential for effective surveillance and epidemiological tracking of influenza viruses. This report describes applications of a resequencing pathogen microarray (RPM) assay that is capable of simultaneous sequencing of su...

  20. Frequently Asked Questions on Human Infection Caused by the Avian Influenza A (H7N9) Virus

    MedlinePlus

    ... to eat meat/animal products, for example, poultry, eggs, and pork? Because influenza viruses are inactivated by ... not be eaten. 10. How can meat and eggs be safely prepared? Always keep raw meat and ...

  1. The use of nonhuman primates in research on seasonal, pandemic and avian influenza, 1893-2014.

    PubMed

    Davis, A Sally; Taubenberger, Jeffery K; Bray, Mike

    2015-05-01

    Attempts to reproduce the features of human influenza in laboratory animals date from the early 1890s, when Richard Pfeiffer inoculated apes with bacteria recovered from influenza patients and produced a mild respiratory illness. Numerous studies employing nonhuman primates (NHPs) were performed during the 1918 pandemic and the following decade. Most used bacterial preparations to infect animals, but some sought a filterable agent for the disease. Since the viral etiology of influenza was established in the early 1930s, studies in NHPs have been supplemented by a much larger number of experiments in mice, ferrets and human volunteers. However, the emergence of a novel swine-origin H1N1 influenza virus in 1976 and the highly pathogenic H5N1 avian influenza virus in 1997 stimulated an increase in NHP research, because these agents are difficult to study in naturally infected patients and cannot be administered to human volunteers. In this paper, we review the published literature on the use of NHPs in influenza research from 1893 through the end of 2014. The first section summarizes observational studies of naturally occurring influenza-like syndromes in wild and captive primates, including serologic investigations. The second provides a chronological account of experimental infections of NHPs, beginning with Pfeiffer's study and covering all published research on seasonal and pandemic influenza viruses, including vaccine and antiviral drug testing. The third section reviews experimental infections of NHPs with avian influenza viruses that have caused disease in humans since 1997. The paper concludes with suggestions for further studies to more clearly define and optimize the role of NHPs as experimental animals for influenza research. PMID:25746173

  2. The use of nonhuman primates in research on seasonal, pandemic and avian influenza, 1893–2014

    PubMed Central

    Davis, A. Sally; Taubenberger, Jeffery K.; Bray, Mike

    2015-01-01

    Attempts to reproduce the features of human influenza in laboratory animals date from the early 1890s, when Richard Pfeiffer inoculated apes with bacteria recovered from influenza patients and produced a mild respiratory illness. Numerous studies employing nonhuman primates (NHPs) were performed during the 1918 pandemic and the following decade. Most used bacterial preparations to infect animals, but some sought a filterable agent for the disease. Since the viral etiology of influenza was established in the early 1930s, studies in NHPs have been supplemented by a much larger number of experiments in mice, ferrets and human volunteers. However, the emergence of a novel swine-origin H1N1 influenza virus in 1976 and the highly pathogenic H5N1 avian influenza virus in 1997 stimulated an increase in NHP research, because these agents are difficult to study in naturally infected patients and cannot be administered to human volunteers. In this paper, we review the published literature on the use of NHPs in influenza research from 1893 through the end of 2014. The first section summarizes observational studies of naturally occurring influenza-like syndromes in wild and captive primates, including serologic investigations. The second provides a chronological account of experimental infections of NHPs, beginning with Pfeiffer’s study and covering all published research on seasonal and pandemic influenza viruses, including vaccine and antiviral drug testing. The third section reviews experimental infections of NHPs with avian influenza viruses that have caused disease in humans since 1997. The paper concludes with suggestions for further studies to more clearly define and optimize the role of NHPs as experimental animals for influenza research. PMID:25746173

  3. Free-grazing Ducks and Highly Pathogenic Avian Influenza, Thailand

    PubMed Central

    Chaitaweesub, Prasit; Parakamawongsa, Tippawon; Premashthira, Sith; Tiensin, Thanawat; Kalpravidh, Wantanee; Wagner, Hans; Slingenbergh, Jan

    2006-01-01

    Thailand has recently had 3 epidemic waves of highly pathogenic avian influenza (HPAI); virus was again detected in July 2005. Risk factors need to be identified to better understand disease ecology and assist HPAI surveillance and detection. This study analyzed the spatial distribution of HPAI outbreaks in relation to poultry, land use, and other anthropogenic variables from the start of the second epidemic wave (July 2004–May 2005). Results demonstrate a strong association between H5N1 virus in Thailand and abundance of free-grazing ducks and, to a lesser extent, native chickens, cocks, wetlands, and humans. Wetlands used for double-crop rice production, where free-grazing duck feed year round in rice paddies, appear to be a critical factor in HPAI persistence and spread. This finding could be important for other duck-producing regions in eastern and southeastern Asian countries affected by HPAI. PMID:16494747

  4. Verification of poultry carcass composting research through application during actual avian influenza outbreaks.

    PubMed

    Flory, Gary A; Peer, Robert W

    2010-01-01

    An avian influenza outbreak in 2002 affected 197 poultry farms in Virginia and cost an estimated $130 million in losses and cleanup. In 2004-2005, researchers initiated a project to investigate the feasibility and practicality of in-house composting of turkey mortalities (heavy hens and toms) as a method of disposal and disease containment. Occurrences of low pathogenic avian influenza (LPAI) in West Virginia and Virginia in 2007 provided an opportunity for first responders to verify composting as an effective carcass disposal method. Many lessons learned from these experiences have led to improvements in the application of this technology. Market-weight turkeys, once thought too large for effective composting, were composted sufficiently for land application within 4 to 6 weeks. Additionally, fire-fighting foam, a new method of mass depopulation, proved to be compatible with composting. Knowledge gained from these incidents will be valuable not only for future responses to LPAI but also for outbreaks of highly pathogenic avian influenza such as the H5N1 virus, which currently causes disease in both animals and humans in many parts of the world. Since three-quarters of all recent emerging infectious diseases (EIDs) have arisen from animals, control of disease in animals is the principal way to reduce human exposure and prevent EIDs. Many of the general approaches and specific techniques used to eradicate the avian influenza virus can also be used to control other EIDs such as H1N1, Nipah virus, Rift Valley Fever, and plague. PMID:20375437

  5. The Irrationality of GOF Avian Influenza Virus Research

    PubMed Central

    Wain-Hobson, Simon

    2014-01-01

    The last two and a half years have witnessed a curious debate in virology characterized by a remarkable lack of discussion. It goes by the misleading epithet “gain of function” (GOF) influenza virus research, or simply GOF. As will be seen, there is nothing good to be gained. The controversial experiments confer aerosol transmission on avian influenza virus strains that can infect humans, but which are not naturally transmitted between humans. Some of the newer strains are clearly highly pathogenic for man. It will be shown here that the benefits of the work are erroneous and overstated while the risk of an accident is finite, if small. The consequence of any accident would be anywhere from a handful of infections to a catastrophic pandemic. There has been a single open international meeting in this period, which is surprising given that openness and discussion are essential to good science. Despite US and EU government funding, no risk–benefit analysis has been published, which again is surprising. This research can be duplicated readily in many labs and requires little high tech. It falls under the definition of DURC without the slightest shadow of a doubt and constitutes the most important challenge facing contemporary biology. PMID:25077136

  6. Avian influenza in Chile: a successful experience.

    PubMed

    Max, Vanessa; Herrera, José; Moreira, Rubén; Rojas, Hernán

    2007-03-01

    Avian influenza (AI) was diagnosed in May 2002 for the first time in Chile and South America. The epidemic was caused by the highly pathogenic AI (HPAI) virus subtype H7N3 that emerged from a low pathogenic virus. The index farm was a broiler breeder, located in San Antonio, V Region, which at the time was a densely populated poultry area. Stamping of 465,000 breeders, in 27 sheds, was immediately conducted. Surveillance activities detected a second outbreak, 1 wk later, at a turkey breeding farm from the same company. The second farm was located 4 km from the index case. Only 25% of the sheds were infected, and 18,500 turkeys were destroyed. In both outbreaks, surveillance zones and across-country control measures were established: prediagnosis quarantine, depopulation, intensive surveillance, movement control, and increased biosecurity. Other measures included cleaning, disinfection, and controlling the farms with sentinels to detect the potential presence of the virus. Zoning procedures were implemented to allow the international trade of poultry products from unaffected areas. Positive serologic results to H5N2 virus also were detected in other poultry farms, but there was no evidence of clinical signs or virus isolation. Epidemiological investigation and laboratory confirmation determined that positive serology was related to a contaminated imported batch of vaccine against inclusion body hepatitis. All actions taken allowed the control of the epidemic, and within 7 mo, Chile was free of AI. Epidemic and control measures that prevented further spread are described in this article, which illustrates the importance of a combination of control measures during and after an outbreak of AI. This study is a good example of how veterinary services need to respond if their country is affected by HPAI. PMID:17494584

  7. Respiratory transmission of an avian H3N8 influenza virus isolated from a harbour seal

    PubMed Central

    Karlsson, Erik A.; Ip, Hon S.; Hall, Jeffrey S.; Yoon, Sun Woo; Johnson, Jordan; Beck, Melinda A.; Webby, Richard J.; Schultz-Cherry, Stacey

    2016-01-01

    The ongoing human H7N9 influenza infections highlight the threat of emerging avian influenza viruses. In 2011, an avian H3N8 influenza virus isolated from moribund New England harbour seals was shown to have naturally acquired mutations known to increase the transmissibility of highly pathogenic H5N1 influenza viruses. To elucidate the potential human health threat, here we evaluate a panel of avian H3N8 viruses and find that the harbour seal virus displays increased affinity for mammalian receptors, transmits via respiratory droplets in ferrets and replicates in human lung cells. Analysis of a panel of human sera for H3N8 neutralizing antibodies suggests that there is no population-wide immunity to these viruses. The prevalence of H3N8 viruses in birds and multiple mammalian species including recent isolations from pigs and evidence that it was a past human pandemic virus make the need for surveillance and risk analysis of these viruses of public health importance. PMID:25183346

  8. Respiratory transmission of an avian H3N8 influenza virus isolated from a harbour seal

    USGS Publications Warehouse

    Karlsson, Erik A.; Ip, Hon S.; Hall, Jeffrey S.; Yoon, Sun W.; Johnson, Jordan; Beck, Melinda A.; Webby, Richard J.; Schultz-Cherry, Stacey

    2014-01-01

    The ongoing human H7N9 influenza infections highlight the threat of emerging avian influenza viruses. In 2011, an avian H3N8 influenza virus isolated from moribund New England harbour seals was shown to have naturally acquired mutations known to increase the transmissibility of highly pathogenic H5N1 influenza viruses. To elucidate the potential human health threat, here we evaluate a panel of avian H3N8 viruses and find that the harbour seal virus displays increased affinity for mammalian receptors, transmits via respiratory droplets in ferrets and replicates in human lung cells. Analysis of a panel of human sera for H3N8 neutralizing antibodies suggests that there is no population-wide immunity to these viruses. The prevalence of H3N8 viruses in birds and multiple mammalian species including recent isolations from pigs and evidence that it was a past human pandemic virus make the need for surveillance and risk analysis of these viruses of public health importance.

  9. Selective Bottlenecks Shape Evolutionary Pathways Taken during Mammalian Adaptation of a 1918-like Avian Influenza Virus.

    PubMed

    Moncla, Louise H; Zhong, Gongxun; Nelson, Chase W; Dinis, Jorge M; Mutschler, James; Hughes, Austin L; Watanabe, Tokiko; Kawaoka, Yoshihiro; Friedrich, Thomas C

    2016-02-10

    Avian influenza virus reassortants resembling the 1918 human pandemic virus can become transmissible among mammals by acquiring mutations in hemagglutinin (HA) and polymerase. Using the ferret model, we trace the evolutionary pathway by which an avian-like virus evolves the capacity for mammalian replication and airborne transmission. During initial infection, within-host HA diversity increased drastically. Then, airborne transmission fixed two polymerase mutations that do not confer a detectable replication advantage. In later transmissions, selection fixed advantageous HA1 variants. Transmission initially involved a "loose" bottleneck, which became strongly selective after additional HA mutations emerged. The stringency and evolutionary forces governing between-host bottlenecks may therefore change throughout host adaptation. Mutations occurred in multiple combinations in transmitted viruses, suggesting that mammalian transmissibility can evolve through multiple genetic pathways despite phenotypic constraints. Our data provide a glimpse into avian influenza virus adaptation in mammals, with broad implications for surveillance on potentially zoonotic viruses. PMID:26867176

  10. Control strategies for highly pathogenic avian influenza: a global perspective.

    PubMed

    Lubroth, J

    2007-01-01

    Comprehensive programmes for the prevention, detection and control of highly pathogenic avian influenza (HPAI) require a national dimension and relevant national legislation in which veterinary services can conduct surveillance, competent diagnosis and rapid response. Avian influenza was controlled and prevented by vaccination long before the current H5N1 crisis. The use of vaccine cannot be separated from other essential elements of a vaccination campaign, which include education in poultry production practices, such as hygiene, all in-all out production concepts, separation of species, biosecurity (bio-exclusion to keep the disease out and biocontainment to keep the disease from spreading once suspected or detected), competence in giving the vaccine and the role of vaccination teams, post-vaccination monitoring to ensure efficacy and to detect the circulation of wild-type virus, surveillance and buffer zones in outbreak areas, and performance indicators to determine when vaccination can cease. Reporting of disease can be improved through well-structured, adequately financed veterinary services and also by fair compensation for producers who suffer financial loss. A rapid response to suspected cases of HPAI should be ensured in simulation exercises involving various sectors of the food production and marketing chain, policy-makers, official veterinary structures and other government personnel. As for other transboundary animal diseases, national approaches must be part of a regional strategy and regional networks for cooperation and information sharing, which in turn reflect global policies and international standards, such as the quality of vaccines, reporting obligations, humane interventions, cleaning and disinfection methods, restocking times, monitoring and safe trade. PMID:18411931

  11. Within-host variation of avian influenza viruses

    PubMed Central

    Iqbal, Munir; Xiao, Hiaxia; Baillie, Greg; Warry, Andrew; Essen, Steve C.; Londt, Brandon; Brookes, Sharon M.; Brown, Ian H.; McCauley, John W.

    2009-01-01

    The emergence and spread of H5N1 avian influenza viruses from Asia through to Europe and Africa pose a significant animal disease problem and have raised concerns that the virus may pose a pandemic threat to humans. The epizootological factors that have influenced the wide distribution of the virus are complex, and the variety of viruses currently circulating reflects these factors. Sequence analysis of the virus genes sheds light on the H5N1 virus evolution during its emergence and spread, but the degree of virus variation at the level of an individual infected bird has been described in only a few studies. Here, we describe some results of a study in which turkeys, ducks and chickens were infected with either one of two H5N1 or one of three H7N1 viruses, and the degree of sequence variation within an individual infected avian host was examined. We developed ‘deep amplicon’ sequence analysis for this work, and the methods and results provide a background framework for application to disease outbreaks in the field. PMID:19687042

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

    PubMed Central

    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

  13. Conducting influenza virus pathogenesis studies in avian species

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian infection studies with influenza A are an important means of assessing host susceptibility, viral pathogenesis, host responses to infection, mechanisms of transmission and viral pathotype. Complex systems and natural settings may also be explored with carefully designed infection studies. In ...

  14. DETECTION OF AVIAN INFLUENZA VIRUS USING AN INTERFEROMETRIC BIOSENSOR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An optical interferometric waveguide immunoassay for direct and label-less detection of avian influenza virus is described. The assay response is based on index of refraction changes that occur upon binding of virus particles to antigen (hemagglutinin) specific antibodies on the waveguide surface. ...

  15. Practical aspects of surveillance for avian influenza in poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The overall approach to surveillance for avian influenza virus (AIV) in poultry will vary depending on the situation, resources, and goals of a given surveillance program. However, the optimal methods for sample collection, transport, and handling are universal. Many practical questions have been ...

  16. Review of rapid molecular diagnostic tools for avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Molecular diagnostics tests are commonly used to diagnose avian influenza virus (AIV) because they are sensitive, can be performed rapidly, with high throughput, and at a moderate cost. Molecular diagnostic tests have recently proven themselves to be invaluable in controlling disease outbreaks arou...

  17. Recent worldwide outbreaks of avian influenza and methods for control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty-five epizootics of high pathogenicity avian influenza (HPAI) have occurred in the world since 1959. The largest of these outbreaks has been the H5N1 HPAI which has caused problems in poultry and other birds in 55 countries of Asia, Europe and Africa since 1996. These viruses have also cause...

  18. Rapidly Expanding Range of Highly Pathogenic Avian Influenza Viruses

    PubMed Central

    Dusek, Robert J.; Spackman, Erica

    2015-01-01

    The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus’ propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions. PMID:26079209

  19. Highly pathogenic avian influenza virus among wild birds in Mongolia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The central Asian country of Mongolia supports large populations of migratory water birds that migrate across much of Asia where highly pathogenic avian influenza (HPAI) virus subtype H5N1 is endemic. This, together with the near absence of domestic poultry, makes Mongolia an ideal location to unde...

  20. Thermal inactivation of avian influenza virus in liquid egg products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Thirty eight percent of the 200 million cases of shelled eggs produced per year in the U.S. are processed as liquid egg product. The U.S. also exports internationally a large amount of egg products. Although the U.S. is normally free of avian influenza, concern about contamination of egg product wit...

  1. Avian Influenza Vaccine Technologies and Laboratory Methods for Assessing Protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines can be used in avian influenza (AI) control programs to prevent, manage or eradicate AI from poultry and other birds. The best protection is produced from the humoral response against the hemagglutinin (HA) protein and such protection is HA subtype specific. A variety of vaccines have been ...

  2. Digital diffraction detection of protein markers for avian influenza.

    PubMed

    Im, Hyungsoon; Park, Yong Il; Pathania, Divya; Castro, Cesar M; Weissleder, Ralph; Lee, Hakho

    2016-04-12

    Rapid pathogen testing is expected to play a critical role in infection control and in limiting epidemics. Smartphones equipped with state-of-the-art computing and imaging technologies have emerged as new point-of-use (POU) sensing platforms. We herein report a new assay format for fast, sensitive and portable detection of avian influenza-associated antibodies. PMID:26980325

  3. Pathobiology of avian influenza virus infections in wild birds

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Individual avian Influenza (AI) viruses vary in their ability to produce infection, disease and death in different bird species. Based on the pathobiological features in chickens, AI viruses (AIV) are categorized as low pathogenicity (LPAI) or high pathogenicity (HPAI) viruses, and can be of any of...

  4. Rumor Surveillance and Avian Influenza H5N1

    PubMed Central

    Patel, Mahomed; Olowokure, Babatunde; Roces, Maria C.; Oshitani, Hitoshi

    2005-01-01

    We describe the enhanced rumor surveillance during the avian influenza H5N1 outbreak in 2004. The World Health Organization’s Western Pacific Regional Office identified 40 rumors; 9 were verified to be true. Rumor surveillance informed immediate public health action and prevented unnecessary and costly responses. PMID:15757567

  5. The changing ecology, epidemiology and pathobiology of avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Twenty-five epizootics of high pathogenicity avian influenza (HPAI) have occurred in the world since 1959. The largest of these outbreaks has been the H5N1 HPAI which has caused problems in poultry and some wild birds in over 60 countries of Asia, Europe and Africa since beginning in 1996. The H5N1 ...

  6. Avian influenza: worldwide situation and effectiveness of current vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The H5N1 high pathogenicity avian influenza (HPAI) virus emerged in China during 1996 and has spread to infect poultry and/or wild birds in 63 countries during the past 18 years. The majority of the recent outbreaks of H5N2 HPAI have occurred in Indonesia, Egypt, Vietnam, and Bangladesh, in decreasi...

  7. Prevention and control of avian influenza in Asia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The H5N1 high pathogenicity avian influenza (HPAI) virus emerged in China during 1996 and has spread to infect poultry and/or wild birds in 62 countries during the past 15 years. For 2011-2012, 19 countries reported outbreaks of H5N1 in domestic poultry, wild birds or both. The majority of the outbr...

  8. Immunohistochemical staining of avian influenza viruses in tissues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunohistochemical methods are commonly used for studying the pathogenesis of avian influenza virus by allowing the identification of sites of replication of the virus in infected tissues and the correlation with the histopathological changes observed. In this chapter, the materials and methods fo...

  9. Innate resistance to avian influenza: Of MHC's and Mx proteins

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) is an economically important virus of poultry that has significant impact on global trade. Recently, increased attention to animal genomics has been applied to enhance innate resistance to infectious diseases in poultry. Two known contributors to innate resistance are the host m...

  10. Canada geese and the epidemiology of avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Canada geese (Branta canadensis) are numerous, highly visible, and widely distributed in both migratory and resident populations in North America; as a member of the Order Anseriformes, they are often suggested as a potential reservoir and source for avian influenza (AI) viruses. To further examine...

  11. Immunohistochemical staining of avian influenza virus in tissues

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Immunohistochemical methods are commonly used for studying the pathogenesis of avian influenza (AI) virus by allowing the identification of sites of replication of the virus in infected tissues and the correlation with the histopathological changes observed. In this chapter, the materials and metho...

  12. The changing role of avian influenza on global health

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Avian influenza (AI) viruses are a diverse group divided into 144 different subtypes based on different combinations of the 16 hemagglutinin and 9 neuraminidase subtypes, and two different pathotypes (low [LP] and high pathogenicity [HP]). LPAI viruses are maintained in wild birds, and must be adapt...

  13. Rapidly expanding range of highly pathogenic avian influenza viruses

    USGS Publications Warehouse

    Hall, Jeffrey S.; Dusek, Robert J.; Spackman, Erica

    2015-01-01

    The movement of highly pathogenic avian influenza (H5N8) virus across Eurasia and into North America and the virus’ propensity to reassort with co-circulating low pathogenicity viruses raise concerns among poultry producers, wildlife biologists, aviculturists, and public health personnel worldwide. Surveillance, modeling, and experimental research will provide the knowledge required for intelligent policy and management decisions.

  14. Rapidly expanding range of highly pathogenic avian influenza viruses

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The recent introduction of highly pathogenic avian influenza virus (HPAIV) H5N8 into Europe and North America poses significant risks to poultry industries and wildlife populations and warrants continued and heightened vigilance. First discovered in South Korean poultry and wild birds in early 2014...

  15. Avian influenza worldwide: current status and successful control tools

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The H5N1 high pathogenicity avian influenza (HPAI) virus emerged in China during 1996 and has spread to infect poultry and/or wild birds in 62 countries during the past 15 years. For 2010-2011, 20 countries reported outbreaks of H5N1 in domestic poultry (n = 11), wild birds (n = 4) or both (n=5). Th...

  16. Avian Influenza vaccine technologies and laboratory methods for assessing protection

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines can be used in avian influenza (AI) control programs to prevent, manage or eradicate AI from poultry and other birds. The best protection is produced from the humoral response against the hemagglutinin (HA) protein and such protection is HA subtype specific. A variety of vaccines have been ...

  17. Avian Influenza Vaccination of Poultry and Passive Case Reporting, Egypt

    PubMed Central

    Grosbois, Vladimir; Jobre, Yilma; Saad, Ahmed; El Nabi, Amira Abd; Galal, Shereen; Kalifa, Mohamed; El Kader, Soheir Abd; Dauphin, Gwenaëlle; Roger, François; Lubroth, Juan; Peyre, Marisa

    2012-01-01

    We investigated the influence of a mass poultry vaccination campaign on passive surveillance of highly pathogenic avian influenza subtype (H5N1) outbreaks among poultry in Egypt. Passive reporting dropped during the campaign, although probability of infection remained unchanged. Future poultry vaccination campaigns should consider this negative impact on reporting for adapting surveillance strategies. PMID:23171740

  18. Movements of birds and avian influenza from Asia into Alaska

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Asian-origin avian influenza (AI) virus is spread in part by migratory birds. We describe the extensive overlap of Asian and American bird vectors in Alaska as the ‘Beringian Crucible’. Seven years of AI surveillance among waterfowl and shorebirds in this region (1998-2004; 8,255 samples) show remar...

  19. Avian influenza virus infection dynamics in shorebird hosts

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Using serial cross-sectional data from 2000-2008 and generalized linear models, we examined temporal trends of springtime avian influenza virus (AIV) prevalence and antibody prevalence in four Charadriiformes species at the Delaware Bay migratory stopover site. Prevalence of AIV in Ruddy Turnstones ...

  20. Scientific basis for use of vaccination as a strategy to control avian influenza

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Vaccines have been used to control a variety of piscian, avian, and mammalian diseases. Commercial usage of vaccines against avian influenza (AI) began in 1979, in Minnesota to control H4 and H6 low pathogenicity avian influenza (LPAI) which was causing economically significant disease in turkey br...

  1. International standards for the control of avian influenza.

    PubMed

    Pearson, J E

    2003-01-01

    The Office International des Epizooties (OIE) has developed international standards to reduce the risk of the spread of high-pathogenicity avian influenza though international trade. These standards include providing a definition of high-pathogenicity avian influenza (HPAI), procedures for prompt reporting of HPAI outbreaks, requirements that must be met for a country or zone to be defined as free of HPAI, requirements that should be met to import live birds and avian products into a HPAI-free country or zone, and the general provisions that countries should meet to reduce the risk of spread of HPAI through trade. The goal of these standards is to facilitate trade while minimizing the risk of the introduction of HPAI. PMID:14575096

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

    PubMed Central

    Kaplan, Bryan S.; Webby, Richard J.

    2013-01-01

    Highly pathogenic H5N1 influenza viruses have been isolated from a number of avian and mammalian species. Despite intensive control measures the number of human and animal cases continues to increase. A more complete understanding of susceptible species and of contributing environmental and molecular factors is crucial if we are to slow the rate of new cases. H5N1 is currently endemic in domestic poultry in only a handful of countries with sporadic and unpredictable spread to other countries. Close contact of terrestrial bird or mammalian species with infected poultry/waterfowl or their biological products is the major route for interspecies transmission. Intra-species transmission of H5N1 in mammals, including humans, has taken place on a limited scale though it remains to be seen if this will change; recent laboratory studies suggest that it is indeed possible. Here we review the avian and mammalian species that are naturally susceptible to H5N1 infection and the molecular factors associated with its expanded host range. PMID:24025480

  3. Personal protective equipment and risk for avian influenza (H7N3).

    PubMed

    Morgan, Oliver; Kuhne, Mirjam; Nair, Pat; Verlander, Neville Q; Preece, Richard; McDougal, Marianne; Zambon, Maria; Reacher, Mark

    2009-01-01

    An outbreak of avian influenza (H7N3) among poultry resulted in laboratory-confirmed disease in 1 of 103 exposed persons. Incomplete use of personal protective equipment (PPE) was associated with conjunctivitis and influenza-like symptoms. Rigorous use of PPE by persons managing avian influenza outbreaks may reduce exposure to potentially hazardous infected poultry materials. PMID:19116052

  4. Personal Protective Equipment and Risk for Avian Influenza (H7N3)

    PubMed Central

    Kuhne, Mirjam; Nair, Pat; Verlander, Neville Q.; Preece, Richard; McDougal, Marianne; Zambon, Maria; Reacher, Mark

    2009-01-01

    An outbreak of avian influenza (H7N3) among poultry resulted in laboratory-confirmed disease in 1 of 103 exposed persons. Incomplete use of personal protective equipment (PPE) was associated with conjunctivitis and influenza-like symptoms. Rigorous use of PPE by persons managing avian influenza outbreaks may reduce exposure to potentially hazardous infected poultry materials. PMID:19116052

  5. Persistence of Highly Pathogenic Avian Influenza Viruses in Natural Ecosystems

    PubMed Central

    Feare, Chris J.; Renaud, François; Thomas, Frédéric; Gauthier-Clerc, Michel

    2010-01-01

    Understanding of ecologic factors favoring emergence and maintenance of highly pathogenic avian influenza (HPAI) viruses is limited. Although low pathogenic avian influenza viruses persist and evolve in wild populations, HPAI viruses evolve in domestic birds and cause economically serious epizootics that only occasionally infect wild populations. We propose that evolutionary ecology considerations can explain this apparent paradox. Host structure and transmission possibilities differ considerably between wild and domestic birds and are likely to be major determinants of virulence. Because viral fitness is highly dependent on host survival and dispersal in nature, virulent forms are unlikely to persist in wild populations if they kill hosts quickly or affect predation risk or migratory performance. Interhost transmission in water has evolved in low pathogenic influenza viruses in wild waterfowl populations. However, oropharyngeal shedding and transmission by aerosols appear more efficient for HPAI viruses among domestic birds. PMID:20587174

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

    PubMed

    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

  7. Outbreak of H7N8 Low Pathogenic Avian Influenza in Commercial Turkeys with Spontaneous Mutation to Highly Pathogenic Avian Influenza.

    PubMed

    Killian, Mary Lea; Kim-Torchetti, Mia; Hines, Nichole; Yingst, Sam; DeLiberto, Thomas; Lee, Dong-Hun

    2016-01-01

    Highly pathogenic avian influenza (HPAI) subtype H7N8 was detected in commercial turkeys in January 2016. Control zone surveillance discovered a progenitor low pathogenic avian influenza (LPAI) virus in surrounding turkey flocks. Data analysis supports a single LPAI virus introduction followed by spontaneous mutation to HPAI on a single premises. PMID:27313288

  8. Outbreak of H7N8 Low Pathogenic Avian Influenza in Commercial Turkeys with Spontaneous Mutation to Highly Pathogenic Avian Influenza

    PubMed Central

    Killian, Mary Lea; Hines, Nichole; Yingst, Sam; DeLiberto, Thomas; Lee, Dong-Hun

    2016-01-01

    Highly pathogenic avian influenza (HPAI) subtype H7N8 was detected in commercial turkeys in January 2016. Control zone surveillance discovered a progenitor low pathogenic avian influenza (LPAI) virus in surrounding turkey flocks. Data analysis supports a single LPAI virus introduction followed by spontaneous mutation to HPAI on a single premises. PMID:27313288

  9. The hemagglutinin structure of an avian H1N1 influenza A virus

    SciTech Connect

    Lin, Tianwei; Wang, Gengyan; Li, Anzhang; Zhang, Qian; Wu, Caiming; Zhang, Rongfu; Cai, Qixu; Song, Wenjun; Yuen, Kwok-Yung

    2009-09-15

    The interaction between hemagglutinin (HA) and receptors is a kernel in the study of evolution and host adaptation of H1N1 influenza A viruses. The notion that the avian HA is associated with preferential specificity for receptors with Sia{alpha}2,3Gal glycosidic linkage over those with Sia{alpha}2,6Gal linkage is not all consistent with the available data on H1N1 viruses. By x-ray crystallography, the HA structure of an avian H1N1 influenza A virus, as well as its complexes with the receptor analogs, was determined. The structures revealed no preferential binding of avian receptor analogs over that of the human analog, suggesting that the HA/receptor binding might not be as stringent as is commonly believed in determining the host receptor preference for some subtypes of influenza viruses, such as the H1N1 viruses. The structure also showed difference in glycosylation despite the preservation of related sequences, which may partly contribute to the difference between structures of human and avian origin.

  10. Live poultry market workers are susceptible to both avian and swine influenza viruses, Guangdong Province, China.

    PubMed

    Chen, Jidang; Ma, Jun; White, Sarah K; Cao, Zhenpeng; Zhen, Yun; He, Shuyi; Zhu, Wanjun; Ke, Changwen; Zhang, Yongbiao; Su, Shuo; Zhang, Guihong

    2015-12-31

    Guangdong Province is recognized for dense populations of humans, pigs, poultry and pets. In order to evaluate the threat of viral infection faced by those working with animals, a cross-sectional, sero-epidemiological study was conducted in Guangdong between December 2013 and January 2014. Individuals working with swine, at poultry farms, or live poultry markets (LPM), and veterinarians, and controls not exposed to animals were enrolled in this study and 11 (4 human, 3 swine, 3 avian, and 1 canine) influenza A viruses were used in hemagglutination inhibition (HI) assays (7 strains) and the cross-reactivity test (9 strains) in which 5 strains were used in both tests. Univariate analysis was performed to identify which variables were significantly associated with seropositivity. Odds ratios (OR) revealed that swine workers had a significantly higher risk of elevated antibodies against A/swine/Guangdong/L6/2009(H1N1), a classical swine virus, and A/swine/Guangdong/SS1/2012(H1N1), a Eurasian avian-like swine virus than non-exposed controls. Poultry farm workers were at a higher risk of infection with avian influenza H7N9 and H9N2. LPM workers were at a higher risk of infection with 3 subtypes of avian influenza, H5N1, H7N9, and H9N2. Interestingly, the OR also indicated that LPM workers were at risk of H1N1 swine influenza virus infection, perhaps due to the presence of pigs in the LPM. While partial confounding by cross-reactive antibodies against human viruses or vaccines cannot be ruled out, our data suggests that animal exposed people as are more likely to have antibodies against animal influenza viruses. PMID:26476563