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Abstract
The H9N2 subtype avian influenza virus (AIV) has become endemic in poultry globally; however due to its low pathogenicity, it is not under primary surveillance and control in many countries. Recent reports of human infection caused by H9N2 AIV has increased public concern. This study investigated the genetic and antigenic characteristics of H9N2 AIV isolated from local markets in nine provinces in Southern China from 2013 to 2018. We detected an increasing annual isolation rate of H9N2 AIV. Phylogenetic analyses of hemagglutinin (HA) genes suggests that isolated strains were rooted in BJ94 lineage but have evolved into new subgroups (II and III), which derived from subgroup I. The estimated substitution rate of the subgroup III strains was 6.23 × 10−3 substitutions/site/year, which was 1.5-fold faster than that of the average H9N2 HA rate (3.95 × 10−3 substitutions/site/year). Based on the antigenic distances, subgroup II and III strains resulted in two clear antigenic clusters 2 and 3, separated from the vaccine strain F98, cluster 1. New antigenic properties of subgroup III viruses were associated with 11 amino acid changes in the HA protein, suggesting antigenic drift in H9N2 viruses. Our phylogenetic and antigenic analyses of the H9N2 strains circulating in local markets in Southern China provide new insights on the antigenic diversification of H9N2 viruses. IMPORTANCE The H9N2 low pathogenicity avian influenza (LPAI) virus has become endemic in poultry globally. In several Asian countries, vaccination against H9N2 avian influenza virus (AIV) was approved to reduce economic losses in the poultry industry. However, surveillance programs initiated after the introduction of vaccination identified the persistence of H9N2 AIV in poultry (especially in chicken in South Korea and China). Recent reports of human infection caused by H9N2 AIV has increased public concern. Surveillance of H9N2 circulating in poultry in the fields or markets was essential to update the vaccination strategies. This study investigated the genetic and antigenic characteristics of H9N2 AIVs isolated from local markets in nine provinces in Southern China from 2013 to 2018. The discovery of mutations in the hemagglutinin (HA) gene that result in antigenic changes provides a baseline reference for evolutionary studies of H9N2 viruses and vaccination strategies in poultry.
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Liu Y, Li S, Sun H, Pan L, Cui X, Zhu X, Feng Y, Li M, Yu Y, Wu M, Lin J, Xu F, Yuan S, Huang S, Sun H, Liao M. Variation and Molecular Basis for Enhancement of Receptor Binding of H9N2 Avian Influenza Viruses in China Isolates. Front Microbiol 2020; 11:602124. [PMID: 33391219 PMCID: PMC7773702 DOI: 10.3389/fmicb.2020.602124] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2020] [Accepted: 11/03/2020] [Indexed: 11/13/2022] Open
Abstract
Currently, H9N2 avian influenza viruses (H9N2 AIVs) globally circulate in poultry and have acquired some adaptation to mammals. However, it is not clear what the molecular basis is for the variation in receptor-binding features of the H9N2 AIVs. The receptor-binding features of 92 H9N2 AIVs prevalent in China during 1994-2017 were characterized through solid-phase ELISA assay and reverse genetics. H9N2 AIVs that circulated in this period mostly belonged to clade h9.4.2. Two increasing incidents occurred in the ability of H9N2 AIVs to bind to avian-like receptors in 2002-2005 and 2011-2014. Two increasing incidents occurred in the strength of H9N2 AIVs to bind to human-like receptors in 2002-2005 and 2011-2017. We found that Q227M, D145G/N, S119R, and R246K mutations can significantly increase H9N2 AIVs to bind to both avian- and human-like receptors. A160D/N, Q156R, T205A, Q226L, V245I, V216L, D208E, T212I, R172Q, and S175N mutations can significantly enhance the strength of H9N2 AIVs to bind to human-like receptors. Our study also identified mutations T205A, D208E, V216L, Q226L, and V245I as the key sites leading to enhanced receptor binding of H9N2 AIVs during 2002-2005 and mutations S119R, D145G, Q156R, A160D, T212I, Q227M, and R246K as the key sites leading to enhanced receptor binding of H9N2 AIVs during 2011-2017. These findings further illustrate the receptor-binding characteristics of avian influenza viruses, which can be a potential threat to public health.
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Affiliation(s)
- Yang Liu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Shuo Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Huapeng Sun
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Liangqi Pan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Xinxin Cui
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Xuhui Zhu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Yaling Feng
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Mingliang Li
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Yanan Yu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Meihua Wu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Jiate Lin
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Fengxiang Xu
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Shaohua Yuan
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Shujian Huang
- School of Life Science and Engineering, Foshan University, Foshan, China
| | - Hailiang Sun
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
| | - Ming Liao
- College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,National and Regional Joint Engineering Laboratory for Medicament of Zoonosis Prevention and Control, College of Veterinary Medicine, South China Agricultural University, Guangzhou, China.,Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou, China.,Key Laboratory of Zoonoses Control and Prevention of Guangdong, Guangzhou, China
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3
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Soda K, Kashiwabara M, Miura K, Ung TTH, Nguyen HLK, Ito H, Le MQ, Ito T. Characterization of H3 subtype avian influenza viruses isolated from poultry in Vietnam. Virus Genes 2020; 56:712-723. [PMID: 32996077 DOI: 10.1007/s11262-020-01797-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2019] [Accepted: 09/14/2020] [Indexed: 11/30/2022]
Abstract
To date, avian influenza viruses (AIVs) have persisted in domestic poultry in wet markets in East Asian countries. We have performed ongoing virus surveillance in poultry populations in Vietnam since 2011, with the goal of controlling avian influenza. Throughout this study, 110 H3 AIVs were isolated from 2760 swab samples of poultry in markets and duck farms. H3 hemagglutinin (HA) genes of the isolates were phylogenetically classified into eight groups (I-VIII). Genetic diversity was also observed in the other seven gene segments. Groups I-IV also included AIVs from wild waterbirds. The epidemic strains in poultry switched from groups I-III and VI to groups I, IV, V, and VIII around 2013. H3 AIVs in groups I and V were maintained in poultry until at least 2016, which likely accompanied their dissemination from the northern to the southern regions of Vietnam. Groups VI-VIII AIVs were antigenically distinct from the other groups. Some H3 AIV isolates had similar N6 neuraminidase and matrix genes as H5 highly pathogenic avian influenza viruses (HPAIVs). These results reveal that genetically and antigenically different H3 AIVs have been co-circulating in poultry in Vietnam. Poultry is usually reared outside in this country and is at risk of infection with wild waterbird-originating AIVs. In poultry flocks, the intruded H3 AIVs must have experienced antigenic drift/shift and genetic reassortment, which could contribute to the emergence of H5 HPAIVs with novel gene constellations.
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Affiliation(s)
- Kosuke Soda
- Department of Joint Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan.,Faculty of Agriculture, Avian Zoonosis Research Center, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan
| | - Mina Kashiwabara
- Department of Joint Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan
| | - Kozue Miura
- Vietnam Research Station, Nagasaki University, c/o National Institute of Hygiene and Epidemiology, No. 1 Yersin Street, Hanoi, Vietnam
| | - Trang T H Ung
- Department of Virology, National Institute of Hygiene and Epidemiology, No. 1 Yersin Street, Hanoi, Vietnam
| | - Hang L K Nguyen
- Department of Virology, National Institute of Hygiene and Epidemiology, No. 1 Yersin Street, Hanoi, Vietnam
| | - Hiroshi Ito
- Department of Joint Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan.,Faculty of Agriculture, Avian Zoonosis Research Center, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan
| | - Mai Q Le
- Department of Virology, National Institute of Hygiene and Epidemiology, No. 1 Yersin Street, Hanoi, Vietnam
| | - Toshihiro Ito
- Department of Joint Veterinary Medicine, Faculty of Agriculture, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan. .,Faculty of Agriculture, Avian Zoonosis Research Center, Tottori University, 4-101 Koyama-Minami, Tottori, 680-8553, Japan.
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The Presence of Poultry Influenza Strains in Two Live Bird Markets near the East-West Boundary of Vietnam. BIOMED RESEARCH INTERNATIONAL 2020; 2020:1487651. [PMID: 32566655 PMCID: PMC7293723 DOI: 10.1155/2020/1487651] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Revised: 04/27/2020] [Accepted: 05/23/2020] [Indexed: 11/18/2022]
Abstract
The spread of avian influenza virus among Asian countries is becoming a concern after influenza epidemics in recent years. This study is aimed at identifying the subtypes of avian influenza viruses collected from healthy chickens and ducks at two live bird markets in a border province of Vietnam and the Lao People Democratic Republic. Cloacal and tracheal swab samples from 100 chickens and 101 ducks were collected in May 2017. All samples were screened to detect avian influenza virus by real-time reverse transcriptase PCR. Samples that are avian influenza virus-positive were isolated in embryonated chicken eggs, and the subtypes were identified by RT-PCR with the specific primers. The samples positive for influenza virus H5 were sequenced to identify HA and NA genes. The prevalence of avian influenza virus (AIV) among chicken and duck samples was 27.5% (55/200) and 24.8% (50/202), respectively. AIV subtypes identified among 17 samples positive with the hemagglutination test include H3N6, H6N6, and H9N2. Of these 17 samples, 7 duck samples were found to be H6N6, 4 duck samples were infected with both subtypes of H3N6 and H6N6, and two chicken samples were recorded as H9N2. A positive chicken sample with A/H5 contains 99% similarity nucleotide with H5N6 reference strain. Results suggested that while the presence of low pathogenic avian influenza virus is predominant, potential risks of the appearance of high pathogen avian influenza virus in the east-west boundary in Vietnam should be concerned and studied further. Furthermore, prevention activities are needed to reduce such biosecurity threats in Vietnam and other Asian countries.
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A Global Perspective on H9N2 Avian Influenza Virus. Viruses 2019; 11:v11070620. [PMID: 31284485 PMCID: PMC6669617 DOI: 10.3390/v11070620] [Citation(s) in RCA: 158] [Impact Index Per Article: 31.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 06/30/2019] [Accepted: 07/01/2019] [Indexed: 11/26/2022] Open
Abstract
H9N2 avian influenza viruses have become globally widespread in poultry over the last two decades and represent a genuine threat both to the global poultry industry but also humans through their high rates of zoonotic infection and pandemic potential. H9N2 viruses are generally hyperendemic in affected countries and have been found in poultry in many new regions in recent years. In this review, we examine the current global spread of H9N2 avian influenza viruses as well as their host range, tropism, transmission routes and the risk posed by these viruses to human health.
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Suttie A, Karlsson EA, Deng YM, Hurt AC, Greenhill AR, Barr IG, Dussart P, Horwood PF. Avian influenza in the Greater Mekong Subregion, 2003-2018. INFECTION GENETICS AND EVOLUTION 2019; 74:103920. [PMID: 31201870 DOI: 10.1016/j.meegid.2019.103920] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Revised: 05/20/2019] [Accepted: 06/11/2019] [Indexed: 12/15/2022]
Abstract
The persistent circulation of avian influenza viruses (AIVs) is an ongoing problem for many countries in South East Asia, causing large economic losses to both the agricultural and health sectors. This review analyses AIV diversity, evolution and the risk of AIV emergence in humans in countries of the Greater Mekong Subregion (GMS): Cambodia, Laos, Myanmar, Thailand and Vietnam (excluding China). The analysis was based on AIV sequencing data, serological studies, published journal articles and AIV outbreak reports available from January 2003 to December 2018. All countries of the GMS have suffered losses due repeated outbreaks of highly pathogenic (HP) H5N1 that has also caused human cases in all GMS countries. In Laos, Myanmar and Vietnam AIV outbreaks in domestic poultry have also been caused by clade 2.3.4.4 H5N6. A diverse range of low pathogenic AIVs (H1-H12) have been detected in poultry and wild bird species, though surveillance for and characterization of these subtypes is limited. Subtype H3, H4, H6 and H11 viruses have been detected over prolonged periods; whilst H1, H2, H7, H8, H10 and H12 viruses have only been detected transiently. H9 AIVs circulate endemically in Cambodia and Vietnam with seroprevalence data indicating human exposure to H9 AIVs in Cambodia, Thailand and Vietnam. As surveillance studies focus heavily on the detection of H5 AIVs in domestic poultry further research is needed to understand the true level of AIV diversity and the risk AIVs pose to humans in the GMS.
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Affiliation(s)
- Annika Suttie
- Virology Unit, Institute Pasteur in Cambodia, Phnom Penh, Cambodia; School of Applied and Biomedical Sciences, Federation University, Churchill, Australia; WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Erik A Karlsson
- Virology Unit, Institute Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Yi-Mo Deng
- WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Aeron C Hurt
- WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Andrew R Greenhill
- School of Applied and Biomedical Sciences, Federation University, Churchill, Australia
| | - Ian G Barr
- WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, Peter Doherty Institute for Infection and Immunity, Melbourne, VIC 3000, Australia
| | - Philippe Dussart
- Virology Unit, Institute Pasteur in Cambodia, Phnom Penh, Cambodia
| | - Paul F Horwood
- College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD 4811, Australia.
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Naguib MM, Verhagen JH, Samy A, Eriksson P, Fife M, Lundkvist Å, Ellström P, Järhult JD. Avian influenza viruses at the wild-domestic bird interface in Egypt. Infect Ecol Epidemiol 2019; 9:1575687. [PMID: 30815236 PMCID: PMC6383604 DOI: 10.1080/20008686.2019.1575687] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 01/24/2019] [Indexed: 12/18/2022] Open
Abstract
Wild birds of the orders Anseriformes (mainly ducks, geese and swans) and Charadriiformes (mainly gulls, terns and waders) constitute the natural reservoir for low pathogenic avian influenza (LPAI) viruses. In Egypt, highly pathogenic avian influenza (HPAI) H5N1 and LPAI H9N2 viruses are endemic in domestic poultry, forming a threat to animal and human health and raising questions about the routes of introduction and mechanisms of persistence. Recently, HPAI H5N8 virus was also introduced into Egyptian domestic birds. Here we review the literature on the role of wild birds in the introduction and endemicity of avian influenza viruses in Egypt. Dabbling ducks in Egypt harbor an extensive LPAI virus diversity and may constitute the route of introduction for HPAI H5N1 and HPAI H5N8 viruses into Egypt through migration, however their role in the endemicity of HPAI H5N1, LPAI H9N2 and potentially other avian influenza virus (AIV) strains - by means of reassortment of viral genes - is less clear. Strengthened surveillance programs, in both domestic and wild birds, that include all LPAI virus subtypes and full genome sequencing are needed to better assess the wild-domestic bird interface and form a basis for evidence-based measures to limit and prevent AIV transmission between wild and domestic birds.
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Affiliation(s)
- Mahmoud M. Naguib
- Zoonosis Science Center, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
- Zoonosis Science Center, Department of Medical Sciences, Uppsala University, Uppsala, Sweden
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
| | - Josanne H. Verhagen
- Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden
| | - Ahmed Samy
- National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Giza, Egypt
- Genetics and Genomics, The Pirbright Institute, Surrey, UK
| | - Per Eriksson
- Zoonosis Science Center, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Mark Fife
- Genetics and Genomics, The Pirbright Institute, Surrey, UK
| | - Åke Lundkvist
- Zoonosis Science Center, Department of Medical Biochemistry and Microbiology, Uppsala University, Uppsala, Sweden
| | - Patrik Ellström
- Zoonosis Science Center, Department of Medical Sciences, Uppsala University, Uppsala, Sweden
| | - Josef D. Järhult
- Zoonosis Science Center, Department of Medical Sciences, Uppsala University, Uppsala, Sweden
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Wang XX, Cheng W, Yu Z, Liu SL, Mao HY, Chen EF. Risk factors for avian influenza virus in backyard poultry flocks and environments in Zhejiang Province, China: a cross-sectional study. Infect Dis Poverty 2018; 7:65. [PMID: 29914558 PMCID: PMC6006748 DOI: 10.1186/s40249-018-0445-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Accepted: 05/30/2018] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Human infection of avian influenza virus (AIV) remains a great concern. Although live poultry markets are believed to be associated with human infections, ever more infections have been reported in rural areas with backyard poultry, especially in the fifth epidemic of H7N9. However, limited information is available on backyard poultry infection and surrounding environmental contamination. METHODS Two surveillance systems and a field survey were used to collect data and samples in Zhejiang Province. In total, 4538 samples were collected by surveillance systems and 3171 from the field survey between May 2015 and May 2017, while 352 backyard poultry owners were interviewed in May 2017 by questionnaire to investigate factors influencing the prevalence of avian influenza A virus and other AIV subtypes. RT-PCR was used to test the nucleic acids of viruses. ArcGIS 10.1 software was used to generate maps. Univariate and logistic regression analyses were conducted to identify risk factors for AIV infection. RESULTS Of the 428 poultry premises observed by the surveillance system, 53 (12.38%) were positive for influenza A virus. Of the 352 samples from poultry premises observed by field survey, 13 (3.39%) were positive for influenza A virus. The prevalence of AIV was unevenly distributed and the dominant subtype differed among cities. Eastern (Shaoxing and Ningbo) and southern (Wenzhou) cities exhibited a higher prevalence of AIV (16.33, 8.94, and 7.30% respectively). Contamination of AIV subtypes was most severe in January, especially in 2016 (23.26%, 70/301). The positive rate of subtype H5/H7/H9 was 2.53% (115/4538). Subtype H5 was the least prevalent, while subtypes H7 and H9 had similar positivity rates (1.50 and 1.32% respectively). Poultry flocks and environmental samples had a similar prevalence of AIV (4.46% vs 5.06%). The type of live birds was a risk factor and the sanitary condition of the setting was a protective factor against influenza A contamination. CONCLUSIONS AIV subtypes were prevalent in backyard poultry flocks and surrounding environments in Zhejiang Province. The types of live birds and sanitary conditions of the environment were associated with influenza A contamination. These findings shine a light on the characteristics of contamination of AIV subtypes and emphasize the importance of reducing AIV circulation in backyard poultry settings.
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Affiliation(s)
- Xiao-Xiao Wang
- Zhejiang Provincial Centre for Disease Control and Prevention, 3399 Binsheng Road, Binjiang District, Hangzhou, Zhejiang 310051 People’s Republic of China
| | - Wei Cheng
- Zhejiang Provincial Centre for Disease Control and Prevention, 3399 Binsheng Road, Binjiang District, Hangzhou, Zhejiang 310051 People’s Republic of China
| | - Zhao Yu
- Zhejiang Provincial Centre for Disease Control and Prevention, 3399 Binsheng Road, Binjiang District, Hangzhou, Zhejiang 310051 People’s Republic of China
| | - She-Lan Liu
- Zhejiang Provincial Centre for Disease Control and Prevention, 3399 Binsheng Road, Binjiang District, Hangzhou, Zhejiang 310051 People’s Republic of China
| | - Hai-Yan Mao
- Zhejiang Provincial Centre for Disease Control and Prevention, 3399 Binsheng Road, Binjiang District, Hangzhou, Zhejiang 310051 People’s Republic of China
| | - En-Fu Chen
- Zhejiang Provincial Centre for Disease Control and Prevention, 3399 Binsheng Road, Binjiang District, Hangzhou, Zhejiang 310051 People’s Republic of China
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9
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Genetic and antigenic characterization of H5, H6 and H9 avian influenza viruses circulating in live bird markets with intervention in the center part of Vietnam. Vet Microbiol 2016; 192:194-203. [PMID: 27527783 DOI: 10.1016/j.vetmic.2016.07.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 07/19/2016] [Accepted: 07/22/2016] [Indexed: 11/20/2022]
Abstract
A total of 3,045 environmental samples and oropharyngeal and cloacal swabs from apparently healthy poultry have been collected at three live bird markets (LBMs) at which practices were applied to reduce avian influenza (AI) virus transmission (intervention LBMs) and six conventional LBMs (non-intervention LBMs) in Thua Thien Hue province in 2014 to evaluate the efficacy of the intervention LBMs. The 178 AI viruses, including H3 (19 viruses), H4 (2), H5 (8), H6 (30), H9 (114), and H11 (5), were isolated from domestic ducks, muscovy ducks, chickens, and the environment. The prevalence of AI viruses in intervention LBMs (6.1%; 95% CI: 5.0-7.5) was similar to that in non-intervention LBMs (5.6%; 95% CI: 4.5-6.8; χ(2)=0.532; df=1; P=0.53) in the study area. Eight H5N6 highly pathogenic avian influenza (HPAI) viruses were isolated from apparently healthy ducks, muscovy ducks, and an environmental sample in an intervention LBM. The hemagglutinin genes of the H5N6 HPAI viruses belonged to the genetic clade 2.3.4.4, and the antigenicity of the H5N6 HPAI viruses differed from the H5N1 HPAI viruses previously circulating in Vietnam. Phylogenetic and antigenic analyses of the H6 and H9 viruses isolated in both types of LBMs revealed that they were closely related to the viruses isolated from domestic birds in China, Group II of H6 viruses and Y280 lineage of H9 viruses. These results indicate that the interventions currently applied in LBMs are insufficient to control AI. A risk analysis should be conducted to identify the key factors contributing to AI virus prevalence in intervention LBMs.
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10
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Horm SV, Tarantola A, Rith S, Ly S, Gambaretti J, Duong V, Y P, Sorn S, Holl D, Allal L, Kalpravidh W, Dussart P, Horwood PF, Buchy P. Intense circulation of A/H5N1 and other avian influenza viruses in Cambodian live-bird markets with serological evidence of sub-clinical human infections. Emerg Microbes Infect 2016; 5:e70. [PMID: 27436362 PMCID: PMC5141262 DOI: 10.1038/emi.2016.69] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 04/13/2016] [Accepted: 04/25/2016] [Indexed: 01/05/2023]
Abstract
Surveillance for avian influenza viruses (AIVs) in poultry and environmental samples was conducted in four live-bird markets in Cambodia from January through November 2013. Through real-time RT-PCR testing, AIVs were detected in 45% of 1048 samples collected throughout the year. Detection rates ranged from 32% and 18% in duck and chicken swabs, respectively, to 75% in carcass wash water samples. Influenza A/H5N1 virus was detected in 79% of samples positive for influenza A virus and 35% of all samples collected. Sequence analysis of full-length haemagglutinin (HA) and neuraminidase (NA) genes from A/H5N1 viruses, and full-genome analysis of six representative isolates, revealed that the clade 1.1.2 reassortant virus associated with Cambodian human cases during 2013 was the only A/H5N1 virus detected during the year. However, multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of HA and NA genes revealed co-circulation of at least nine low pathogenic AIVs from HA1, HA2, HA3, HA4, HA6, HA7, HA9, HA10 and HA11 subtypes. Four repeated serological surveys were conducted throughout the year in a cohort of 125 poultry workers. Serological testing found an overall prevalence of 4.5% and 1.8% for antibodies to A/H5N1 and A/H9N2, respectively. Seroconversion rates of 3.7 and 0.9 cases per 1000 person-months participation were detected for A/H5N1 and A/H9N2, respectively. Peak AIV circulation was associated with the Lunar New Year festival. Knowledge of periods of increased circulation of avian influenza in markets should inform intervention measures such as market cleaning and closures to reduce risk of human infections and emergence of novel AIVs.
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Affiliation(s)
- Srey Viseth Horm
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Arnaud Tarantola
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Sareth Rith
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Sowath Ly
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Juliette Gambaretti
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Veasna Duong
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Phalla Y
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - San Sorn
- National Veterinary Research Institute, Ministry of Agriculture, Forestry and Fisheries, Phnom Penh 12000, Cambodia
| | - Davun Holl
- National Veterinary Research Institute, Ministry of Agriculture, Forestry and Fisheries, Phnom Penh 12000, Cambodia
| | - Lotfi Allal
- Food and Agriculture Organization, Phnom Penh 12000, Cambodia
| | | | - Philippe Dussart
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Paul F Horwood
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia
| | - Philippe Buchy
- Institute Pasteur in Cambodia, Institute Pasteur International Network, Phnom Penh 12000, Cambodia.,GlaxoSmithKline Pte Ltd, Singapore 189720, Singapore
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11
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Thuy DM, Peacock TP, Bich VTN, Fabrizio T, Hoang DN, Tho ND, Diep NT, Nguyen M, Hoa LNM, Trang HTT, Choisy M, Inui K, Newman S, Trung NV, van Doorn R, To TL, Iqbal M, Bryant JE. Prevalence and diversity of H9N2 avian influenza in chickens of Northern Vietnam, 2014. INFECTION GENETICS AND EVOLUTION 2016; 44:530-540. [PMID: 27340015 PMCID: PMC5036934 DOI: 10.1016/j.meegid.2016.06.038] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Revised: 06/17/2016] [Accepted: 06/19/2016] [Indexed: 12/23/2022]
Abstract
Despite their classification as low pathogenicity avian influenza viruses (LPAIV), A/H9N2 viruses cause significant losses in poultry in many countries throughout Asia, the Middle East and North Africa. To date, poultry surveillance in Vietnam has focused on detection of influenza H5 viruses, and there is limited understanding of influenza H9 epidemiology and transmission dynamics. We determined prevalence and diversity of influenza A viruses in chickens from live bird markets (LBM) of 7 northern Vietnamese provinces, using pooled oropharyngeal swabs collected from October to December 2014. Screening by real time RT-PCR revealed 1207/4900 (24.6%) of pooled swabs to be influenza A virus positive; overall prevalence estimates after accounting for pooling (5 swabs/pools) were 5.8% (CI 5.4–6.0). Subtyping was performed on 468 pooled swabs with M gene Ct < 26. No influenza H7 was detected; 422 (90.1%) were H9 positive; and 22 (4.7%) were H5 positive. There was no evidence was of interaction between H9 and H5 virus detection rates. We sequenced 17 whole genomes of A/H9N2, 2 of A/H5N6, and 11 partial genomes. All H9N2 viruses had internal genes that clustered with genotype 57 and were closely related to Chinese human isolates of A/H7N9 and A/H10N8. Using a nucleotide divergence cutoff of 98%, we identified 9 distinct H9 genotypes. Phylogenetic analysis suggested multiple introductions of H9 viruses to northern Vietnam rather than in-situ transmission. Further investigations of H9 prevalence and diversity in other regions of Vietnam are warranted to assess H9 endemicity elsewhere in the country. We report detection of highly pathogenic avian influenza (HPAI) from healthy chickens in Live Bird Markets of Vietnam. Because all breeds of domestic chickens are extremely susceptible to HPAI, we speculate that HPAI detections from market chickens may reflect infections that occur after arrival in the market. Alternatively, shedding of HPAI from healthy birds may reflect vaccine-induced protective immunity that mitigates disease but does not block viral infection. As many as 49% of all pooled surveillance swabs were positive for influenza A virus, corresponding to an overall Influenza A prevalence of 5.45% (95% Confidence Interval 5.4-6.0%). Low pathogenicity avian influenza (LPAI) H9N2 accounted for the vast majority of all influenza A detections in market chickens sampled from 9 northern provinces. To date there is no evidence to suggest an interaction effect between circulation of H5 and H9 viruses; however sampling strategies that involve pooling of surveillance swabs from multiple birds greatly complicates the assessment of co-infection rates or evaluation of epidemiological associations.
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Affiliation(s)
- Duong Mai Thuy
- National Center for Veterinary Diagnostics, Department of Animal Health, Hanoi, Vietnam
| | - Thomas P Peacock
- Avian Viral Diseases programme, The Pirbright Institute, Woking, UK; St Mary's Campus, Imperial College London, London, UK
| | - Vu Thi Ngoc Bich
- Oxford University Clinical Research Unit and Wellcome Trust Major Overseas Programme, Hanoi, Vietnam
| | - Thomas Fabrizio
- St Jude's Center for Excellence in Influenza Research and Surveillance, Memphis, TN, USA
| | - Dang Nguyen Hoang
- Division of Epidemiology, Department of Animal Health, Hanoi, Vietnam
| | - Nguyen Dang Tho
- MIVEGEC (UM1-UM2-CNRS 5290-IRD 224), Centre de Recherche IRD, Montpellier, France
| | - Nguyen Thi Diep
- Division of Epidemiology, Department of Animal Health, Hanoi, Vietnam
| | - Minh Nguyen
- Oxford University Clinical Research Unit and Wellcome Trust Major Overseas Programme, Hanoi, Vietnam
| | - Le Nguyen Minh Hoa
- Oxford University Clinical Research Unit and Wellcome Trust Major Overseas Programme, Hanoi, Vietnam
| | - Hau Thi Thu Trang
- Oxford University Clinical Research Unit and Wellcome Trust Major Overseas Programme, Hanoi, Vietnam
| | - Marc Choisy
- Oxford University Clinical Research Unit and Wellcome Trust Major Overseas Programme, Hanoi, Vietnam; MIVEGEC (UM1-UM2-CNRS 5290-IRD 224), Centre de Recherche IRD, Montpellier, France
| | - Ken Inui
- Food and Agriculture Organization of the United Nations, Hanoi, Vietnam
| | - Scott Newman
- Food and Agriculture Organization of the United Nations, Hanoi, Vietnam
| | | | - Rogier van Doorn
- Oxford University Clinical Research Unit and Wellcome Trust Major Overseas Programme, Hanoi, Vietnam; Center for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Thanh Long To
- National Center for Veterinary Diagnostics, Department of Animal Health, Hanoi, Vietnam
| | - Munir Iqbal
- Avian Viral Diseases programme, The Pirbright Institute, Woking, UK
| | - Juliet E Bryant
- Oxford University Clinical Research Unit and Wellcome Trust Major Overseas Programme, Hanoi, Vietnam; Center for Tropical Medicine, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK.
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12
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Pantin-Jackwood MJ, Costa-Hurtado M, Miller PJ, Afonso CL, Spackman E, Kapczynski DR, Shepherd E, Smith D, Swayne DE. Experimental co-infections of domestic ducks with a virulent Newcastle disease virus and low or highly pathogenic avian influenza viruses. Vet Microbiol 2015; 177:7-17. [PMID: 25759292 PMCID: PMC4388808 DOI: 10.1016/j.vetmic.2015.02.008] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 02/05/2015] [Accepted: 02/06/2015] [Indexed: 11/16/2022]
Abstract
Infections with avian influenza viruses (AIV) of low and high pathogenicity (LP and HP) and Newcastle disease virus (NDV) are commonly reported in domestic ducks in many parts of the world. However, it is not clear if co-infections with these viruses affect the severity of the diseases they produce, the amount of virus shed, and transmission of the viruses. In this study we infected domestic ducks with a virulent NDV virus (vNDV) and either a LPAIV or a HPAIV by giving the viruses individually, simultaneously, or sequentially two days apart. No clinical signs were observed in ducks infected or co-infected with vNDV and LPAIV, but co-infection decreased the number of ducks shedding vNDV and the amount of virus shed (P<0.01) at 4 days post inoculation (dpi). Co-infection did not affect the number of birds shedding LPAIV, but more LPAIV was shed at 2 dpi (P<0.0001) from ducks inoculated with only LPAIV compared to ducks co-infected with vNDV. Ducks that received the HPAIV with the vNDV simultaneously survived fewer days (P<0.05) compared to the ducks that received the vNDV two days before the HPAIV. Co-infection also reduced transmission of vNDV to naïve contact ducks housed with the inoculated ducks. In conclusion, domestic ducks can become co-infected with vNDV and LPAIV with no effect on clinical signs but with reduction of virus shedding and transmission. These findings indicate that infection with one virus can interfere with replication of another, modifying the pathogenesis and transmission of the viruses.
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Affiliation(s)
- Mary J Pantin-Jackwood
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA.
| | - Mar Costa-Hurtado
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
| | - Patti J Miller
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
| | - Claudio L Afonso
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
| | - Erica Spackman
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
| | - Darrell R Kapczynski
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
| | - Eric Shepherd
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
| | - Diane Smith
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
| | - David E Swayne
- Exotic and Emerging Avian Viral Diseases Unit, Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, GA 30605, USA
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