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Fusaro A, Zecchin B, Giussani E, Palumbo E, Agüero-García M, Bachofen C, Bálint Á, Banihashem F, Banyard AC, Beerens N, Bourg M, Briand FX, Bröjer C, Brown IH, Brugger B, Byrne AMP, Cana A, Christodoulou V, Dirbakova Z, Fagulha T, Fouchier RAM, Garza-Cuartero L, Georgiades G, Gjerset B, Grasland B, Groza O, Harder T, Henriques AM, Hjulsager CK, Ivanova E, Janeliunas Z, Krivko L, Lemon K, Liang Y, Lika A, Malik P, McMenamy MJ, Nagy A, Nurmoja I, Onita I, Pohlmann A, Revilla-Fernández S, Sánchez-Sánchez A, Savic V, Slavec B, Smietanka K, Snoeck CJ, Steensels M, Svansson V, Swieton E, Tammiranta N, Tinak M, Van Borm S, Zohari S, Adlhoch C, Baldinelli F, Terregino C, Monne I. High pathogenic avian influenza A(H5) viruses of clade 2.3.4.4b in Europe-Why trends of virus evolution are more difficult to predict. Virus Evol 2024; 10:veae027. [PMID: 38699215 PMCID: PMC11065109 DOI: 10.1093/ve/veae027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/01/2024] [Accepted: 03/26/2024] [Indexed: 05/05/2024] Open
Abstract
Since 2016, A(H5Nx) high pathogenic avian influenza (HPAI) virus of clade 2.3.4.4b has become one of the most serious global threats not only to wild and domestic birds, but also to public health. In recent years, important changes in the ecology, epidemiology, and evolution of this virus have been reported, with an unprecedented global diffusion and variety of affected birds and mammalian species. After the two consecutive and devastating epidemic waves in Europe in 2020-2021 and 2021-2022, with the second one recognized as one of the largest epidemics recorded so far, this clade has begun to circulate endemically in European wild bird populations. This study used the complete genomes of 1,956 European HPAI A(H5Nx) viruses to investigate the virus evolution during this varying epidemiological outline. We investigated the spatiotemporal patterns of A(H5Nx) virus diffusion to/from and within Europe during the 2020-2021 and 2021-2022 epidemic waves, providing evidence of ongoing changes in transmission dynamics and disease epidemiology. We demonstrated the high genetic diversity of the circulating viruses, which have undergone frequent reassortment events, providing for the first time a complete overview and a proposed nomenclature of the multiple genotypes circulating in Europe in 2020-2022. We described the emergence of a new genotype with gull adapted genes, which offered the virus the opportunity to occupy new ecological niches, driving the disease endemicity in the European wild bird population. The high propensity of the virus for reassortment, its jumps to a progressively wider number of host species, including mammals, and the rapid acquisition of adaptive mutations make the trend of virus evolution and spread difficult to predict in this unfailing evolving scenario.
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Affiliation(s)
- Alice Fusaro
- European Reference Laboratory (EURL) for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell'universita 10, Legnaro, Padua 35020, Italy
| | - Bianca Zecchin
- European Reference Laboratory (EURL) for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell'universita 10, Legnaro, Padua 35020, Italy
| | - Edoardo Giussani
- European Reference Laboratory (EURL) for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell'universita 10, Legnaro, Padua 35020, Italy
| | - Elisa Palumbo
- European Reference Laboratory (EURL) for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell'universita 10, Legnaro, Padua 35020, Italy
| | - Montserrat Agüero-García
- Ministry of Agriculture, Fisheries and Food, Laboratorio Central de Veterinaria (LCV), Ctra. M-106, Km 1,4 Algete, Madrid 28110, Spain
| | - Claudia Bachofen
- Federal Department of Home Affairs FDHA Institute of Virology and Immunology IVI, Sensemattstrasse 293, Mittelhäusern 3147, Switzerland
| | - Ádám Bálint
- Veterinary Diagnostic Directorate (NEBIH), Laboratory of Virology, National Food Chain Safety Office, Tábornok utca 2, Budapest 1143, Hungary
| | - Fereshteh Banihashem
- Department of Microbiology, National Veterinary Institute (SVA), Travvägen 20, Uppsala 75189, Sweden
| | - Ashley C Banyard
- WOAH/FAO international reference laboratory for Avian Influenza and Newcastle Disease, Virology Department, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone KT15 3NB, United Kingdom
| | - Nancy Beerens
- Department of Virology Wageningen Bioveterinary Research, Houtribweg 39, Lelystad 8221 RA, The Netherlands
| | - Manon Bourg
- Luxembourgish Veterinary and Food Administration (ALVA), State Veterinary Laboratory, 1 Rue Louis Rech, Dudelange 3555, Luxembourg
| | - Francois-Xavier Briand
- Agence Nationale de Sécurité Sanitaire, de l’Alimentation, de l’Environnement et du Travail, Laboratoire de Ploufragan-Plouzané-Niort, Unité de Virologie, Immunologie, Parasitologie Avaires et Cunicoles, 41 Rue de Beaucemaine – BP 53, Ploufragan 22440, France
| | - Caroline Bröjer
- Department of Pathology and Wildlife Disease, National Veterinary Institute (SVA), Travvägen 20, Uppsala 75189, Sweden
| | - Ian H Brown
- WOAH/FAO international reference laboratory for Avian Influenza and Newcastle Disease, Virology Department, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone KT15 3NB, United Kingdom
| | - Brigitte Brugger
- Icelandic Food and Veterinary Authority, Austurvegur 64, Selfoss 800, Iceland
| | - Alexander M P Byrne
- WOAH/FAO international reference laboratory for Avian Influenza and Newcastle Disease, Virology Department, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone KT15 3NB, United Kingdom
| | - Armend Cana
- Kosovo Food and Veterinary Agency, Sector of Serology and Molecular Diagnostics, Kosovo Food and Veterinary Laboratory, Str Lidhja e Pejes, Prishtina 10000, Kosovo
| | - Vasiliki Christodoulou
- Laboratory for Animal Health Virology Section Veterinary Services (1417), 79, Athalassa Avenue Aglantzia, Nicosia 2109, Cyprus
| | - Zuzana Dirbakova
- Department of Animal Health, State Veterinary Institute, Pod Dráhami 918, Zvolen 96086, Slovakia
| | - Teresa Fagulha
- I.P. (INIAV, I.P.), Avenida da República, Instituto Nacional de Investigação Agrária e Veterinária, Quinta do Marquês, Oeiras 2780 – 157, Portugal
| | - Ron A M Fouchier
- Department of Viroscience, Erasmus MC, Dr. Molewaterplein 40, Rotterdam 3015 GD, The Netherlands
| | - Laura Garza-Cuartero
- Department of Agriculture, Food and the Marine, Central Veterinary Research Laboratory (CVRL), Backweston Campus, Stacumny Lane, Celbridge, Co. Kildare W23 X3PH, Ireland
| | - George Georgiades
- Thessaloniki Veterinary Centre (TVC), Department of Avian Diseases, 26th October Street 80, Thessaloniki 54627, Greece
| | - Britt Gjerset
- Immunology & Virology department, Norwegian Veterinary Institute, Arboretveien 57, Oslo Pb 64, N-1431 Ås, Norway
| | - Beatrice Grasland
- Agence Nationale de Sécurité Sanitaire, de l’Alimentation, de l’Environnement et du Travail, Laboratoire de Ploufragan-Plouzané-Niort, Unité de Virologie, Immunologie, Parasitologie Avaires et Cunicoles, 41 Rue de Beaucemaine – BP 53, Ploufragan 22440, France
| | - Oxana Groza
- Republican Center for Veterinary Diagnostics (NRL), 3 street Murelor, Chisinau 2051, Republic of Moldova
| | - Timm Harder
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, Greifswald-Insel Riems 17493, Germany
| | - Ana Margarida Henriques
- I.P. (INIAV, I.P.), Avenida da República, Instituto Nacional de Investigação Agrária e Veterinária, Quinta do Marquês, Oeiras 2780 – 157, Portugal
| | - Charlotte Kristiane Hjulsager
- Department for Virus and Microbiological Special Diagnostics, Statens Serum Institut, 5 Artillerivej, Copenhagen DK-2300, Denmark
| | - Emiliya Ivanova
- National Reference Laboratory for Avian Influenza and Newcastle Disease, National Diagnostic and Research Veterinary Medical Institute (NDRVMI), 190 Lomsko Shose Blvd., Sofia 1231, Bulgaria
| | - Zygimantas Janeliunas
- National Food and Veterinary Risk Assessment Institute (NFVRAI), Kairiukscio str. 10, Vilnius 08409, Lithuania
| | - Laura Krivko
- Institute of Food Safety, Animal Health and Environment (BIOR), Laboratory of Microbilogy and Pathology, 3 Lejupes Street, Riga 1076, Latvia
| | - Ken Lemon
- Virological Molecular Diagnostic Laboratory, Veterinary Sciences Division, Department of Virology, Agri-Food and Bioscience Institute (AFBI), Stoney Road, Belfast BT4 3SD, Northern Ireland
| | - Yuan Liang
- Department of Veterinary and Animal Sciences, University of Copenhagen, Grønnegårdsvej 15, Frederiksberg 1870, Denmark
| | - Aldin Lika
- Animal Health Department, Food Safety and Veterinary Institute, Rruga Aleksandër Moisiu 10, Tirana 1001, Albania
| | - Péter Malik
- Veterinary Diagnostic Directorate (NEBIH), Laboratory of Virology, National Food Chain Safety Office, Tábornok utca 2, Budapest 1143, Hungary
| | - Michael J McMenamy
- Virological Molecular Diagnostic Laboratory, Veterinary Sciences Division, Department of Virology, Agri-Food and Bioscience Institute (AFBI), Stoney Road, Belfast BT4 3SD, Northern Ireland
| | - Alexander Nagy
- Department of Molecular Biology, State Veterinary Institute Prague, Sídlištní 136/24, Praha 6-Lysolaje 16503, Czech Republic
| | - Imbi Nurmoja
- National Centre for Laboratory Research and Risk Assessment (LABRIS), Kreutzwaldi 30, Tartu 51006, Estonia
| | - Iuliana Onita
- Institute for Diagnosis and Animal Health (IDAH), Str. Dr. Staicovici 63, Bucharest 050557, Romania
| | - Anne Pohlmann
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Südufer 10, Greifswald-Insel Riems 17493, Germany
| | - Sandra Revilla-Fernández
- Austrian Agency for Health and Food Safety (AGES), Institute for Veterinary Disease Control, Robert Koch Gasse 17, Mödling 2340, Austria
| | - Azucena Sánchez-Sánchez
- Ministry of Agriculture, Fisheries and Food, Laboratorio Central de Veterinaria (LCV), Ctra. M-106, Km 1,4 Algete, Madrid 28110, Spain
| | - Vladimir Savic
- Croatian Veterinary Institute, Poultry Centre, Heinzelova 55, Zagreb 10000, Croatia
| | - Brigita Slavec
- University of Ljubljana – Veterinary Faculty/National Veterinary Institute, Gerbičeva 60, Ljubljana 1000, Slovenia
| | - Krzysztof Smietanka
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantow 57, Puławy 24-100, Poland
| | - Chantal J Snoeck
- Luxembourg Institute of Health (LIH), Department of Infection and Immunity, 29 Rue Henri Koch, Esch-sur-Alzette 4354, Luxembourg
| | - Mieke Steensels
- Avian Virology and Immunology, Sciensano, Rue Groeselenberg 99, Ukkel 1180, Ukkel, Belgium
| | - Vilhjálmur Svansson
- Biomedical Center, Institute for Experimental Pathology, University of Iceland, Keldnavegi 3 112 Reykjavík Ssn. 650269 4549, Keldur 851, Iceland
| | - Edyta Swieton
- Department of Poultry Diseases, National Veterinary Research Institute, Al. Partyzantow 57, Puławy 24-100, Poland
| | - Niina Tammiranta
- Finnish Food Authority, Animal Health Diagnostic Unit, Veterinary Virology, Mustialankatu 3, Helsinki FI-00790, Finland
| | - Martin Tinak
- Department of Animal Health, State Veterinary Institute, Pod Dráhami 918, Zvolen 96086, Slovakia
| | - Steven Van Borm
- Avian Virology and Immunology, Sciensano, Rue Groeselenberg 99, Ukkel 1180, Ukkel, Belgium
| | - Siamak Zohari
- Department of Microbiology, National Veterinary Institute (SVA), Travvägen 20, Uppsala 75189, Sweden
| | - Cornelia Adlhoch
- European Centre for Disease Prevention and Control, Gustav III:s boulevard 40, Solna 169 73, Sweden
| | | | - Calogero Terregino
- European Reference Laboratory (EURL) for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell'universita 10, Legnaro, Padua 35020, Italy
| | - Isabella Monne
- European Reference Laboratory (EURL) for Avian Influenza and Newcastle Disease, Istituto Zooprofilattico Sperimentale delle Venezie, viale dell'universita 10, Legnaro, Padua 35020, Italy
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Adlhoch C, Alm E, Enkirch T, Lamb F, Melidou A, Willgert K, Marangon S, Monne I, Stegeman JA, Delacourt R, Baldinelli F, Broglia A. Drivers for a pandemic due to avian influenza and options for One Health mitigation measures. EFSA J 2024; 22:e8735. [PMID: 38576537 PMCID: PMC10988447 DOI: 10.2903/j.efsa.2024.8735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/06/2024] Open
Abstract
Avian influenza viruses (AIV) remain prevalent among wild bird populations in the European Union and European Economic Area (EU/EEA), leading to significant illness in and death of birds. Transmission between bird and mammal species has been observed, particularly in fur animal farms, where outbreaks have been reported. While transmission from infected birds to humans is rare, there have been instances of exposure to these viruses since 2020 without any symptomatic infections reported in the EU/EEA. However, these viruses continue to evolve globally, and with the migration of wild birds, new strains carrying potential mutations for mammalian adaptation could be selected. If avian A(H5N1) influenza viruses acquire the ability to spread efficiently among humans, large-scale transmission could occur due to the lack of immune defences against H5 viruses in humans. The emergence of AIV capable of infecting mammals, including humans, can be facilitated by various drivers. Some intrinsic drivers are related to virus characteristics or host susceptibility. Other drivers are extrinsic and may increase exposure of mammals and humans to AIV thereby stimulating mutation and adaptation to mammals. Extrinsic drivers include the ecology of host species, such as including wildlife, human activities like farming practices and the use of natural resources, climatic and environmental factors. One Health measures to mitigate the risk of AIV adapting to mammals and humans focus on limiting exposure and preventing spread. Key options for actions include enhancing surveillance targeting humans and animals, ensuring access to rapid diagnostics, promoting collaboration between animal and human sectors, and implementing preventive measures such as vaccination. Effective communication to different involved target audiences should be emphasised, as well as strengthening veterinary infrastructure, enforcing biosecurity measures at farms, and reducing wildlife contact with domestic animals. Careful planning of poultry and fur animal farming, especially in areas with high waterfowl density, is highlighted for effective risk reduction.
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Martelli L, Fornasiero D, Scarton F, Spada A, Scolamacchia F, Manca G, Mulatti P. Study of the Interface between Wild Bird Populations and Poultry and Their Potential Role in the Spread of Avian Influenza. Microorganisms 2023; 11:2601. [PMID: 37894259 PMCID: PMC10609042 DOI: 10.3390/microorganisms11102601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/17/2023] [Accepted: 10/19/2023] [Indexed: 10/29/2023] Open
Abstract
Water birds play a crucial role in disseminating and amplifying avian influenza viruses (AIVs) in the environment. However, they may have limited interactions with domestic facilities, raising the hypothesis that other wild birds may play the bridging role in introducing AIVs into poultry. An ornithocoenosis study, based on census-transect and camera-trapping methods, was conducted in 2019 in ten poultry premises in northeast Italy to characterize the bird communities and envisage the species that might act as bridge hosts for AIVs. The data collected were explored through a series of multivariate analyses (correspondence analysis and non-metric multidimensional scaling), and biodiversity indices (observed and estimated richness, Shannon entropy and Pielou's evenness). The analyses revealed a high level of complexity in the ornithic population, with 147 censused species, and significant qualitative and quantitative differences in wild bird species composition, both in space and in time. Among these, only a few were observed in close proximity to the farm premises (i.e., Magpies, Blackbirds, Cattle Egrets, Pheasants, Eurasian Collared Doves, and Wood Pigeons), thus suggesting their potential role in spilling over AIVs to poultry; contrarily, waterfowls appeared to be scarcely inclined to close visits, especially during autumn and winter seasons. These findings stress the importance of ongoing research on the wild-domestic bird interface, advocating for a wider range of species to be considered in AIVs surveillance and prevention programs.
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Affiliation(s)
- Luca Martelli
- Istituto Zooprofilattico Sperimentale delle Venezie, 35020 Legnaro, Italy; (L.M.); (F.S.); (G.M.)
| | - Diletta Fornasiero
- Istituto Zooprofilattico Sperimentale delle Venezie, 35020 Legnaro, Italy; (L.M.); (F.S.); (G.M.)
| | | | - Arianna Spada
- SELC Soc. Coop., 30175 Venice, Italy; (F.S.); (A.S.)
| | - Francesca Scolamacchia
- Istituto Zooprofilattico Sperimentale delle Venezie, 35020 Legnaro, Italy; (L.M.); (F.S.); (G.M.)
| | - Grazia Manca
- Istituto Zooprofilattico Sperimentale delle Venezie, 35020 Legnaro, Italy; (L.M.); (F.S.); (G.M.)
| | - Paolo Mulatti
- Istituto Zooprofilattico Sperimentale delle Venezie, 35020 Legnaro, Italy; (L.M.); (F.S.); (G.M.)
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Jung Kjær L, Ward MP, Boklund AE, Larsen LE, Hjulsager CK, Kirkeby CT. Using surveillance data for early warning modelling of highly pathogenic avian influenza in Europe reveals a seasonal shift in transmission, 2016-2022. Sci Rep 2023; 13:15396. [PMID: 37717056 PMCID: PMC10505205 DOI: 10.1038/s41598-023-42660-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Accepted: 09/13/2023] [Indexed: 09/18/2023] Open
Abstract
Avian influenza in wild birds and poultry flocks constitutes a problem for animal welfare, food security and public health. In recent years there have been increasing numbers of outbreaks in Europe, with many poultry flocks culled after being infected with highly pathogenic avian influenza (HPAI). Continuous monitoring is crucial to enable timely implementation of control to prevent HPAI spread from wild birds to poultry and between poultry flocks within a country. We here utilize readily available public surveillance data and time-series models to predict HPAI detections within European countries and show a seasonal shift that happened during 2021-2022. The output is models capable of monitoring the weekly risk of HPAI outbreaks, to support decision making.
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Affiliation(s)
- Lene Jung Kjær
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
| | - Michael P Ward
- Faculty of Science, Sydney School of Veterinary Science, University of Sydney, Camden, NSW, Australia
| | - Anette Ella Boklund
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Lars Erik Larsen
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | | | - Carsten Thure Kirkeby
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
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Foret-Lucas C, Figueroa T, Coggon A, Houffschmitt A, Dupré G, Fusade-Boyer M, Guérin JL, Delverdier M, Bessière P, Volmer R. In Vitro and In Vivo Characterization of H5N8 High-Pathogenicity Avian Influenza Virus Neurotropism in Ducks and Chickens. Microbiol Spectr 2023; 11:e0422922. [PMID: 36625654 PMCID: PMC9927090 DOI: 10.1128/spectrum.04229-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 12/01/2022] [Indexed: 01/11/2023] Open
Abstract
H5N8 high-pathogenicity avian influenza virus (HPAIV) of clade 2.3.4.4B, which circulated during the 2016 epizootics in Europe, was notable for causing different clinical signs in ducks and chickens. The clinical signs preceding death were predominantly neurological in ducks versus respiratory in chickens. To investigate the determinants for the predominant neurological signs observed in ducks, we infected duck and chicken primary cortical neurons. Viral replication was identical in neuronal cultures from both species. In addition, we did not detect any major difference in the immune and inflammatory responses. These results suggest that the predominant neurological involvement of H5N8 HPAIV infection in ducks could not be recapitulated in primary neuronal cultures. In vivo, H5N8 HPAIV replication in ducks peaked soon after infection and led to an early colonization of the central nervous system. In contrast, viral replication was delayed in chickens but ultimately burst in the lungs of chickens, and the chickens died of respiratory distress before brain damage became significant. Consequently, the immune and inflammatory responses in the brain were significantly higher in duck brains than those in chickens. Our study thus suggests that early colonization of the central nervous system associated with prolonged survival after the onset of virus replication is the likely primary cause of the sustained inflammatory response and subsequent neurological disorders observed in H5N8 HPAIV-infected ducks. IMPORTANCE The severity of high-pathogenicity avian influenza virus (HPAIV) infection has been linked to its ability to replicate systemically and cause lesions in a variety of tissues. However, the symptomatology depends on the host species. The H5N8 virus of clade 2.3.4.4B had a pronounced neurotropism in ducks, leading to severe neurological disorders. In contrast, neurological signs were rarely observed in chickens, which suffered mostly from respiratory distress. Here, we investigated the determinants of H5N8 HPAIV neurotropism. We provide evidence that the difference in clinical signs was not due to a difference in neurotropism. Our results rather indicate that chickens died of respiratory distress due to intense viral replication in the lungs before viral replication in the brain could produce significant lesions. In contrast, ducks better controlled virus replication in the lungs, thus allowing the virus to replicate for a sufficient duration in the brain, to reach high levels, and to cause significant lesions.
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Affiliation(s)
- Charlotte Foret-Lucas
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Thomas Figueroa
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Amelia Coggon
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Alexandre Houffschmitt
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Gabriel Dupré
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Maxime Fusade-Boyer
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Jean-Luc Guérin
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Maxence Delverdier
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Pierre Bessière
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Romain Volmer
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
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Ahrens AK, Selinka HC, Mettenleiter TC, Beer M, Harder TC. Exploring surface water as a transmission medium of avian influenza viruses - systematic infection studies in mallards. Emerg Microbes Infect 2022; 11:1250-1261. [PMID: 35473641 PMCID: PMC9090351 DOI: 10.1080/22221751.2022.2065937] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Mallards (Anas platyrhynchos) are an abundant anseriform migratory wild bird species worldwide and an important reservoir for the maintenance of low pathogenicity (LP) avian influenza viruses (AIV). They have also been implicated in the spread of high pathogenicity (HP) AIV after spill-over events from HPAIV-infected poultry. The spread of HPAIV within wild water bird populations may lead to viral contamination of natural habitats. The role of small shallow water bodies as a transmission medium of AIV among mallards is investigated here in three experimental settings. (i) Delayed onset but rapid progression of infection seeded by two mallards inoculated with either LP or HP AIV to each eight sentinel mallards was observed in groups with access to a small 100 L water pool. In contrast, groups with a bell drinker as the sole source of drinking water showed a rapid onset but lengthened course of infection. (ii) HPAIV infection also set off when virus was dispersed in the water pool; titres as low as 102 TCID50 L-1 (translating to 0.1 TCID50 mL-1) proved to be sufficient. (iii) Substantial loads of viral RNA (and infectivity) were also found on the surface of the birds' breast plumage. "Unloading" of virus infectivity from contaminated plumage into water bodies may be an efficient mechanism of virus spread by infected mallards. However, transposure of HPAIV via the plumage of an uninfected mallard failed. We conclude, surface water in small shallow water bodies may play an important role as a mediator of AIV infection of aquatic wild birds.
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Affiliation(s)
- Ann Kathrin Ahrens
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, Isle of Riems, Germany
| | | | | | - Martin Beer
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, Isle of Riems, Germany
| | - Timm C Harder
- Institute of Diagnostic Virology, Friedrich-Loeffler-Institute, Isle of Riems, Germany
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7
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Grant M, Bröjer C, Zohari S, Nöremark M, Uhlhorn H, Jansson DS. Highly Pathogenic Avian Influenza (HPAI H5Nx, Clade 2.3.4.4.b) in Poultry and Wild Birds in Sweden: Synopsis of the 2020-2021 Season. Vet Sci 2022; 9:344. [PMID: 35878361 PMCID: PMC9318561 DOI: 10.3390/vetsci9070344] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/04/2022] [Accepted: 07/05/2022] [Indexed: 11/16/2022] Open
Abstract
Highly pathogenic avian influenza (HPAI, Gs/Gd lineage) was introduced to Europe in 2005 and has since caused numerous outbreaks in birds. The 2020-2021 season was the hitherto most devastating when considering bird numbers and duration in Europe. Surveillance data, virologic results and epidemiologic investigations from the 2020-2021 outbreaks in Sweden were analysed. Subtypes H5N8 and H5N5 were detected on 24 farms with poultry or other captive birds. In wild birds, subtypes H5N8, H5N5, H5N1, H5N4, H5Nx were detected in 130 out of 811 sampled birds. There was a spatiotemporal association between cases in wild birds and poultry. Based on phylogeny and epidemiology, most of the introductions of HPAI to commercial poultry were likely a result of indirect contact with wild birds. A definite route of introduction to poultry could not be established although some biosecurity breaches were observed. No spread between farms was identified but airborne spread between flocks on the same farm was suspected. Our findings exemplify the challenges posed by the continuously changing influenza viruses that seem to adapt to a broader species spectrum. This points to the importance of wild bird surveillance, compliance to biosecurity, and identification of risk factors for introduction on poultry farms.
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Affiliation(s)
- Malin Grant
- Department of Disease Control and Epidemiology, National Veterinary Institute, 751 89 Uppsala, Sweden; (M.G.); (M.N.)
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
| | - Caroline Bröjer
- Department of Pathology and Wildlife Diseases, National Veterinary Institute, 751 89 Uppsala, Sweden; (C.B.); (H.U.)
| | - Siamak Zohari
- Department of Microbiology, National Veterinary Institute, 751 89 Uppsala, Sweden;
| | - Maria Nöremark
- Department of Disease Control and Epidemiology, National Veterinary Institute, 751 89 Uppsala, Sweden; (M.G.); (M.N.)
| | - Henrik Uhlhorn
- Department of Pathology and Wildlife Diseases, National Veterinary Institute, 751 89 Uppsala, Sweden; (C.B.); (H.U.)
| | - Désirée S. Jansson
- Department of Clinical Sciences, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden
- Department of Animal Health and Antimicrobial Strategies, National Veterinary Institute, 751 89 Uppsala, Sweden
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8
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Has Epizootic Become Enzootic? Evidence for a Fundamental Change in the Infection Dynamics of Highly Pathogenic Avian Influenza in Europe, 2021. mBio 2022; 13:e0060922. [PMID: 35726917 PMCID: PMC9426456 DOI: 10.1128/mbio.00609-22] [Citation(s) in RCA: 49] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Phylogenetic evidence from the recent resurgence of high-pathogenicity avian influenza (HPAI) virus subtype H5N1, clade 2.3.4.4b, observed in European wild birds and poultry since October 2021, suggests at least two different and distinct reservoirs. We propose contrasting hypotheses for this emergence: (i) resident viruses have been maintained, presumably in wild birds, in northern Europe throughout the summer of 2021 to cause some of the outbreaks that are part of the most recent autumn/winter 2021 epizootic, or (ii) further virus variants were reintroduced by migratory birds, and these two sources of reintroduction have driven the HPAI resurgence. Viruses from these two principal sources can be distinguished by their hemagglutinin genes, which segregate into two distinct sublineages (termed B1 and B2) within clade 2.3.4.4b, as well as their different internal gene compositions. The evidence of enzootic HPAI virus circulation during the summer of 2021 indicates a possible paradigm shift in the epidemiology of HPAI in Europe.
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9
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Bessière P, Figueroa T, Coggon A, Foret-Lucas C, Houffschmitt A, Fusade-Boyer M, Dupré G, Guérin JL, Delverdier M, Volmer R. Opposite Outcomes of the Within-Host Competition between High- and Low-Pathogenic H5N8 Avian Influenza Viruses in Chickens Compared to Ducks. J Virol 2022; 96:e0136621. [PMID: 34613804 PMCID: PMC8754203 DOI: 10.1128/jvi.01366-21] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Accepted: 10/01/2021] [Indexed: 11/20/2022] Open
Abstract
Highly pathogenic avian influenza viruses (HPAIV) emerge from low-pathogenic avian influenza viruses (LPAIV) through the introduction of basic amino acids at the hemagglutinin (HA) cleavage site. Following viral evolution, the newly formed HPAIV likely represents a minority variant within the index host, predominantly infected with the LPAIV precursor. Using reverse genetics-engineered H5N8 viruses differing solely at the HA cleavage, we tested the hypothesis that the interaction between the minority HPAIV and the majority LPAIV could modulate the risk of HPAIV emergence and that the nature of the interaction could depend on the host species. In chickens, we observed that the H5N8LP increased H5N8HP replication and pathogenesis. In contrast, the H5N8LP antagonized H5N8HP replication and pathogenesis in ducks. Ducks mounted a more potent antiviral innate immune response than chickens against the H5N8LP, which correlated with H5N8HP inhibition. These data provide experimental evidence that HPAIV may be more likely to emerge in chickens than in ducks and underscore the importance of within-host viral variant interactions in viral evolution. IMPORTANCE Highly pathogenic avian influenza viruses represent a threat to poultry production systems and to human health because of their impact on food security and because of their zoonotic potential. It is therefore crucial to better understand how these viruses emerge. Using a within-host competition model between high- and low-pathogenic avian influenza viruses, we provide evidence that highly pathogenic avian influenza viruses could be more likely to emerge in chickens than in ducks. These results have important implications for highly pathogenic avian influenza virus emergence prevention, and they underscore the importance of within-host viral variant interactions in virus evolution.
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Affiliation(s)
- Pierre Bessière
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Thomas Figueroa
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Amelia Coggon
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Charlotte Foret-Lucas
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Alexandre Houffschmitt
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Maxime Fusade-Boyer
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Gabriel Dupré
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Jean-Luc Guérin
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Maxence Delverdier
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
| | - Romain Volmer
- Ecole Nationale Vétérinaire de Toulouse, Université de Toulouse, ENVT, INRAE, IHAP, UMR 1225, Toulouse, France
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10
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Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin‐Bastuji B, Gonzales Rojas JL, Gortázar Schmidt C, Herskin M, Michel V, Miranda Chueca MÁ, Padalino B, Pasquali P, Spoolder H, Ståhl K, Velarde A, Viltrop A, Winckler C, Gubbins S, Stegeman JA, Antoniou S, Aznar I, Broglia A, Van der Stede Y, Zancanaro G, Roberts HC. Assessment of the control measures of the category A diseases of Animal Health Law: Newcastle disease. EFSA J 2021; 19:e06946. [PMID: 34900005 PMCID: PMC8638556 DOI: 10.2903/j.efsa.2021.6946] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
EFSA received a mandate from the European Commission to assess the effectiveness of some of the control measures against diseases included in the Category A list according to Regulation (EU) 2016/429 on transmissible animal diseases ('Animal Health Law'). This opinion belongs to a series of opinions where these control measures will be assessed, with this opinion covering the assessment of control measures for Newcastle disease (ND). In this opinion, EFSA and the AHAW Panel of experts review the effectiveness of: (i) clinical and laboratory sampling procedures, (ii) monitoring period and (iii) the minimum radius of the protection and surveillance zone, and the minimum length of time the measures should be applied in these zones. The general methodology used for this series of opinions has been published elsewhere. Several scenarios for which these control measures had to be assessed were designed and agreed prior to the start of the assessment. The monitoring period (21 days) was assessed as effective in non-vaccinated chicken and turkey flocks, although large uncertainty remains surrounding the effectiveness of this period in vaccinated galliform flocks and flocks of other bird species. It was also concluded that the protection (3 km radius) and the surveillance (10 km radius) zones contain 99% of the infections from an infectious establishment. Recommendations provided for each of the scenarios assessed aim to support the European Commission in the drafting of further pieces of legislation, as well as for plausible ad hoc requests in relation to ND.
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11
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Adlhoch C, Fusaro A, Gonzales JL, Kuiken T, Marangon S, Niqueux É, Staubach C, Terregino C, Aznar I, Guajardo IM, Lima E, Baldinelli F. Avian influenza overview February - May 2021. EFSA J 2021; 19:e06951. [PMID: 34925560 PMCID: PMC8647004 DOI: 10.2903/j.efsa.2021.6951] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The 2020-2021 epidemic with a total of 3,555 reported HPAI detections and around 22,400,000 affected poultry birds in 28 European Countries appears to be one of the largest and most devastating HPAI epidemics ever occurred in Europe. Between 24 February and 14 May 2021, 1,672 highly pathogenic avian influenza (HPAI) virus detections were reported in 24 EU/EEA countries and the UK in poultry (n=580), and in wild (n=1,051) and captive birds (n=41). The majority of the detections in poultry were reported by Poland that accounted for 297 outbreaks occurring in a densely populated poultry area over a short period of time, followed by Germany with 168 outbreaks. Germany accounted for 603 detections in wild birds, followed by Denmark and Poland with 167 and 56 detections, respectively. A second peak of HPAI-associated wild bird mortality was observed from February to April 2021 in north-west Europe. The observed longer persistence of HPAI in wild birds compared to previous years may result in a continuation of the risk for juveniles of wild birds and mammals, as well as for virus entry into poultry farms. Therefore, enhanced awareness among farmers to continue applying stringent biosecurity measures and to monitor and report increases in daily mortality and drops in production parameters, are recommended. Sixteen different genotypes were identified to date in Europe and Russia, suggesting a high propensity of these viruses to reassort. The viruses characterized to date retain a preference for avian-type receptors; however, transmission events to mammals and the identification of sporadic mutations of mammal adaptation, indicate ongoing evolution processes and possible increased ability of viruses within this clade to further adapt and transmit to mammals including humans. Since the last report, two human infections due to A(H5N6) HPAI were reported from China and Laos and 10 human cases due to A(H9N2) low pathogenic avian influenza (LPAI) virus identified in China and Cambodia. The risk of infection for the general population in the EU/EEA is assessed as very low and for occupationally exposed people low. People exposed during avian influenza outbreaks should adhere to protection measures, strictly wear personal protective equipment and get tested immediately when developing respiratory symptoms or conjunctivitis within 10 days after exposure.
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12
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Adlhoch C, Fusaro A, Gonzales JL, Kuiken T, Marangon S, Niqueux É, Staubach C, Terregino C, Aznar I, Muñoz Guajardo I, Baldinelli F. Avian influenza overview September - December 2021. EFSA J 2021; 19:e07108. [PMID: 34987626 PMCID: PMC8698678 DOI: 10.2903/j.efsa.2021.7108] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Between 16 September and 8 December 2021, 867 highly pathogenic avian influenza (HPAI) virus detections were reported in 27 EU/EEA countries and the UK in poultry (316), in wild (523) and in captive birds (28). The detections in poultry were mainly reported by Italy (167) followed by Hungary and Poland (35 each). Tha majority of the detections in wild birds were reported by Germany (280), Netherlands (65) and United Kingdom (53). The observed persistence and continuous circulation of HPAI viruses in migratory and resident wild birds will continue to pose a risk for the poultry industry in Europe for the coming months. The frequent occurrence of HPAI A(H5) incursions in commercial farms (including poultry production types considered at low avian influenza risk) raises concern about the capacity of the applied biosecurity measures to prevent virus introduction. Short-term preparedness and medium- and long-term prevention strategies, including revising and reinforcing biosecurity measures, reduction of the density of commercial poultry farms and possible appropriate vaccination strategies, should be implemented. The results of the genetic analysis indicate that the viruses characterised during this reporting period belong to clade 2.3.4.4b. Some of the characterized HPAI A(H5N1) viruses detected in Sweden, Germany, Poland and United Kingdom are related to the viruses which have been circulating in Europe since October 2020; in North, Central, South and East Europe novel reassortant A(H5N1) virus has been introduced starting from October 2021. HPAI A(H5N1) was also detected in wild mammal species in Sweden, Estonia and Finland; some of these strains characterised so far present an adaptive marker that is associated with increased virulence and replication in mammals. Since the last report, 13 human infections due to HPAI A(H5N6) and two human cases due to LPAI A(H9N2) virus have been reported from China. Some of these A(H5N6) cases were caused by a reassortant virus of clade 2.3.4.4b, which possessed an HA gene closely related to the A(H5) viruses circulating in Europe. The risk of infection for the general population in the EU/EEA is assessed as low, and for occupationally exposed people, low to medium, with large uncertainty due to the high diversity of circulating viruses in the bird populations.
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13
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Aznar I, Baldinelli F, Papanikolaou A, Stoicescu A, Van der Stede Y. Annual Report on surveillance for avian influenza in poultry and wild birds in Member States of the European Union in 2020. EFSA J 2021; 19:e06953. [PMID: 34925561 PMCID: PMC8647014 DOI: 10.2903/j.efsa.2021.6953] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
In 2020, Council Directive 2005/94/EC required EU Member States (MSs) to carry out surveillance for avian influenza (AI) in poultry and wild birds and notify the results to the responsible authority. Based on this, MSs, Iceland, Norway, Switzerland and the United Kingdom implemented ongoing surveillance programmes to monitor incursions of AI viruses in poultry and wild birds. EFSA received a mandate from the European Commission to collate, validate, analyse and summarise the data resulting from the avian influenza surveillance programmes in an annual report. This is the second such report produced using data directly submitted to EFSA by MSs. This report summarises the results of the surveillance activities carried out in poultry and wild birds in 2020. Overall, 24,768 poultry establishments (PEs) were sampled, of which 46 were seropositive for H5 virus strains and seven for H7 strains. Seropositive PEs were found in nine MSs (Belgium, Denmark, Finland, France, Italy, the Netherlands, Poland, Spain and Sweden) and the United Kingdom. As per previous years, the highest percentages of seropositive PEs were found in establishments raising waterfowl game birds and breeding geese. Out of the 53 PEs with positive serological tests for H5/H7, seven tested positive in polymerase chain reaction (PCR) or virology for H5/H7 virus strains: six for Low Pathogenic Avian Influenza (LPAI) and one for Highly Pathogenic Avian Influenza (HPAI). In addition, 13 countries also reported PCR results from 748 PEs which did not correspond to the follow-up testing of a positive serology event (e.g. in some PEs, PCR tests were used for screening). Twenty-five of these PEs were found positive for AI viral RNA. These positive PEs were located in Bulgaria, Estonia, Germany, Romania and Slovakia. A total of 18,968 wild birds were sampled, with 878 birds testing positive to HPAI virus. Fourteen countries reported HPAI-positive wild birds, with all HPAI strains identified as H5. Most positive birds were infected with H5N8, with a smaller number of N1, N3, N5 and unidentified NA subtypes. In addition, there were 317 birds testing positive for LPAI H5 or H7 virus and 429 birds testing positive for non-H5/H7 AI virus, reported by 31 countries. The surveillance findings for poultry and wild birds for 2020 are discussed in relation to the current knowledge of the epidemiology of AI in Europe, in particular the H5N8 epidemic which has been identified late 2020.
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14
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Heterogeneity of Early Host Response to Infection with Four Low-Pathogenic H7 Viruses with a Different Evolutionary History in the Field. Viruses 2021; 13:v13112323. [PMID: 34835129 PMCID: PMC8620788 DOI: 10.3390/v13112323] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 11/12/2021] [Accepted: 11/17/2021] [Indexed: 12/15/2022] Open
Abstract
Once low-pathogenic avian influenza viruses (LPAIVs) of the H5 and H7 subtypes from wild birds enter into poultry species, there is the possibility of them mutating into highly pathogenic avian influenza viruses (HPAIVs), resulting in severe epizootics with up to 100% mortality. This mutation from a LPAIV to HPAIV strain is the main cause of an AIV’s major economic impact on poultry production. Although AIVs are inextricably linked to their hosts in their evolutionary history, the contribution of host-related factors in the emergence of HPAI viruses has only been marginally explored so far. In this study, transcriptomic sequencing of tracheal tissue from chickens infected with four distinct LP H7 viruses, characterized by a different history of pathogenicity evolution in the field, was implemented. Despite the inoculation of a normalized infectious dose of viruses belonging to the same subtype (H7) and pathotype (LPAI), the use of animals of the same age, sex and species as well as the identification of a comparable viral load in the target samples, the analyses revealed a heterogeneity in the gene expression profile in response to infection with each of the H7 viruses administered.
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15
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Bisset AT, Hoyne GF. An Outbreak of Highly Pathogenic Avian Influenza (H7N7) in Australia and the Potential for Novel Influenza A Viruses to Emerge. Microorganisms 2021; 9:microorganisms9081639. [PMID: 34442718 PMCID: PMC8401172 DOI: 10.3390/microorganisms9081639] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Revised: 07/29/2021] [Accepted: 07/30/2021] [Indexed: 11/23/2022] Open
Abstract
In 2020, several geographically isolated farms in Victoria, Australia, experienced an outbreak of highly pathogenic avian influenza (HPAI) virus H7N7 and low pathogenic avian influenza (LPAI) viruses H5N2 and H7N6. Effective containment and control measures ensured the eradication of these viruses but the event culminated in substantial loss of livestock and significant economic impact. The avian HPAI H7N7 virus generally does not infect humans; however, evidence shows the ocular pathway presents a favourable tissue tropism for human infection. Through antigenic drift, mutations in the H7N7 viral genome may increase virulence and pathogenicity in humans. The Victorian outbreak also detected LPAI H7N6 in emus at a commercial farm. Novel influenza A viruses can emerge by mixing different viral strains in a host susceptible to avian and human influenza strains. Studies show that emus are susceptible to infections from a wide range of influenza viral subtypes, including H5N1 and the pandemic H1N1. The emu’s internal organs and tissues express abundant cell surface sialic acid receptors that favour the attachment of avian and human influenza viruses, increasing the potential for internal genetic reassortment and the emergence of novel influenza A viruses. This review summarises the historical context of H7N7 in Australia, considers the potential for increased virulence and pathogenesis through mutations and draws attention to the emu as potentially an unrecognised viral mixing vessel.
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Affiliation(s)
- Andrew T. Bisset
- School of Nursing, Midwifery, Health Sciences and Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, University of Notre Dame Australia, Fremantle, WA 6160, Australia;
- Correspondence:
| | - Gerard F. Hoyne
- School of Nursing, Midwifery, Health Sciences and Physiotherapy, Faculty of Medicine, Nursing and Health Sciences, University of Notre Dame Australia, Fremantle, WA 6160, Australia;
- Institute for Health Research, University of Notre Dame Australia, Fremantle, WA 6160, Australia
- Centre for Cell Therapy and Regenerative Medicine, School of Biomedical Sciences, The University of Western Australia, Nedlands, WA 6009, Australia
- School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA 6027, Australia
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Adlhoch C, Fusaro A, Gonzales JL, Kuiken T, Marangon S, Niqueux É, Staubach C, Terregino C, Muñoz Guajardo I, Lima E, Baldinelli F. Avian influenza overview December 2020 - February 2021. EFSA J 2021; 19:e06497. [PMID: 33717356 PMCID: PMC7927793 DOI: 10.2903/j.efsa.2021.6497] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
Between 8 December 2020 and 23 February 2021, 1,022 highly pathogenic avian influenza (HPAI) virus detectionswere reported in 25 EU/EEA countries and the UK in poultry (n=592), wild (n=421) and captive birds (n=9).The majority of the detections were reported by Francethat accounted for 442 outbreaks in poultry,mostly located inthe Landes regionandaffecting the foie gras production industry,and six wild bird detections; Germany,who reported 207 detections in wild birds and 50 poultry outbreaks; Denmark,with 63 detections in wild birds and one poultry outbreak; and Poland,with 37 poultry outbreaks and 24 wild bird detections. Due to the continued presence of HPAI A(H5) viruses in wild birds and the environment,there is still a risk of avian influenza incursions with the potential further spread between establishments, primarily in areas with high poultry densities. As the currently circulating HPAI A(H5N8) virus cancause high mortality also in affected duck farms, mortality eventscan be seen as a good indicator of virus presence. However,also subclinical virusspread in this type of poultry production system have been reported.To improve early detection of infection in poultry within the surveillance zone, the clinical inspection of duck establishments should be complemented by encouraging farmers to collect dead birds to be pooled and tested weekly (bucket sampling).Six different genotypes were identified to date in Europe and Russia, suggesting a high propensity of these viruses to undergo multiple reassortment events. To date, no evidence of fixation of known mutations previously described as associated to zoonotic potential has been observed in HPAI viruses currently circulanting in Europe based on the available sequences.Seven cases due to A(H5N8) HPAI virus have been reported from Russia, all were poultry workerswith mild or no symptoms. Five human cases due to A(H5N6) HPAI and 10 cases due to A(H9N2) LPAI viruseshave been reported from China. The risk for the general population as well as travel-related imported human cases is assessed as very lowand the risk forpeople occupationally exposedpeople as low.Any human infections with avian influenza viruses are notifiablewithin 24 hoursthrough the Early Warning and Response System (EWRS) and the International Health Regulations (IHR) notification system.
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17
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Nielsen SS, Alvarez J, Bicout DJ, Calistri P, Depner K, Drewe JA, Garin‐Bastuji B, Gonzales Rojas JL, Schmidt CG, Herskin M, Michel V, Miranda Chueca MÁ, Pasquali P, Roberts HC, Sihvonen LH, Spoolder H, Stahl K, Calvo AV, Viltrop A, Winckler C, De Clercq K, Klement E, Stegeman JA, Gubbins S, Antoniou S, Broglia A, Van der Stede Y, Zancanaro G, Aznar I. Scientific Opinion on the assessment of the control measures of the category A diseases of Animal Health Law: Highly Pathogenic Avian Influenza. EFSA J 2021; 19:e06372. [PMID: 33488812 PMCID: PMC7812451 DOI: 10.2903/j.efsa.2021.6372] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
EFSA received a mandate from the European Commission to assess the effectiveness of some of the control measures against diseases included in the Category A list according to Regulation (EU) 2016/429 on transmissible animal diseases ('Animal Health Law'). This opinion belongs to a series of opinions where these control measures will be assessed, with this opinion covering the assessment of control measures for Highly Pathogenic Avian Influenza (HPAI). In this opinion, EFSA and the AHAW Panel of experts review the effectiveness of: (i) clinical and laboratory sampling procedures, (ii) monitoring period and (iii) the minimum radius of the protection and surveillance zone, and the minimum length of time the measures should be applied in these zones. The general methodology used for this series of opinions has been published elsewhere; nonetheless, specific details of the model used for the assessment of the laboratory sampling procedures for HPAI are presented here. Here, also, the transmission kernels used for the assessment of the minimum radius of the protection and surveillance zones are shown. Several scenarios for which these control measures had to be assessed were designed and agreed prior to the start of the assessment. In summary, sampling procedures as described in the diagnostic manual for HPAI were considered efficient for gallinaceous poultry, whereas additional sampling is advised for Anseriformes. The monitoring period was assessed as effective, and it was demonstrated that the surveillance zone comprises 95% of the infections from an affected establishment. Recommendations provided for each of the scenarios assessed aim to support the European Commission in the drafting of further pieces of legislation, as well as for plausible ad hoc requests in relation to HPAI.
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Baldinelli F, Papanikolaou A, Stoicescu A, Van der Stede Y, Aznar I. Annual Report on surveillance for Avian Influenza in poultry and wild birds in Member States of the European Union in 2019. EFSA J 2020; 18:e06349. [PMID: 33343737 PMCID: PMC7737617 DOI: 10.2903/j.efsa.2020.6349] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Context. Avian influenza (AI) is an infectious viral disease that affects all species of domestic and wild birds. The viruses causing this disease can be of high (HPAI) or low (LPAI) pathogenicity and represent a continuous threat to poultry in Europe. Council Directive 2005/94/EC requires EU Member States (MSs) to carry out surveillance in poultry and wild birds and notify the results to the responsible authority. Therefore, MSs, Iceland, Norway, Switzerland and the United Kingdom have implemented ongoing surveillance programmes to monitor incursions of AI viruses in poultry and wild birds. EFSA received a mandate from the European Commission to collate, validate, analyse and summarise the data resulting from the avian influenza surveillance programmes in an annual report. Poultry. Overall 24,419 poultry establishments (PEs) were sampled, of which 87 were seropositive for H5 virus strains and 22 for H7 strains. Seropositive PEs were found in eight MSs (Belgium, Bulgaria, Denmark, France, Germany, the Netherlands, Poland, Spain) and the United Kingdom (also a MS at the time of collection). The highest percentage of seropositive PEs was found in establishments raising waterfowl game birds and breeding geese. Out of the 109 PEs with positive serological tests for H5/H7, only two tested positive in PCR and virology for H5/H7 virus strains, both of which were LPAI strains (H5N1 and H7N7, respectively) and were reported by Denmark. In addition, 12 countries also reported PCR results from 653 PEs carried out either as a screening test or subsequent to a negative serological test result. Five of these PEs were found positive for AI viral RNA: four H5N8 HPAI in Bulgaria and one H7N3 LPAI in Italy. Wild birds. A total of 19,661 dead/moribund wild birds were sampled, with one bird testing positive to HPAI virus H5N6, which was reported by Denmark. In addition, there were 84 birds testing positive for LPAI H5 or H7 virus and 848 birds testing positive for non-H5/H7 AI virus, reported by 30 countries. The surveillance findings for poultry and wild birds for 2019 are discussed in relation to findings from previous years and current knowledge of the epidemiology of AI in Europe.
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Adlhoch C, Fusaro A, Gonzales JL, Kuiken T, Marangon S, Niqueux É, Staubach C, Terregino C, Baldinelli F. Avian influenza overview August - December 2020. EFSA J 2020; 18:e06379. [PMID: 33343738 PMCID: PMC7744019 DOI: 10.2903/j.efsa.2020.6379] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Between 15 August and 7 December 2020, 561highly pathogenic avian influenza (HPAI) virus detections were reported in 15EU/EEA countries and UK in wild birds, poultry andcaptive birds, with Germany (n=370), Denmark (n=65), the Netherlands (n=57) being the most affected countries.The majority of the detections have been reported in wild birds(n=510), primarily in barnacle goose, greylag goose, andEurasian wigeon. Raptors have also been detected infected, particularly common buzzard. The majority of the birds had been found dead or moribund,however, there are also reports ofHPAI virus infection in apparently healthy ducks or geese.A total of 43 HPAI outbreaks were notified in poultry;with signs of avian influenza infection being observed in at least 33 outbreaks;the most likely source of infection was indirect contact with wild birds. Three HPAI virus subtypes, A(H5N8) (n=518), A(H5N5) (n=17) and A(H5N1) (n=6),and four different genotypes were identified, suggesting the occurrence of multiple virus introductions into Europe.The reassortant A(H5N1) virus identified in EU/EEA countries has acquired gene segments from low pathogenic viruses and is not related to A(H5N1) viruses of e.g. clade 2.3.2.1c causing human infections outside of Europe. As the autumn migration of wild waterbirds to their wintering areasin Europe continues, and given the expected local movements of these birds, there is still a high risk of introduction andfurther spread ofHPAI A(H5) viruses within Europe.The risk of virus spread from wild birds to poultry is high and Member States should enforce in 'high risk areas' of their territories the measures provided for in Commission Implementing Decision (EU) 2018/1136.Detection of outbreaks in breeder farms in Denmark, the Netherlands and United Kingdom, highlight also the risk of introduction via contaminated materials (bedding/straw) and equipment.Maintaining high and sustainable surveillance and biosecurityparticularly in high-risk areas is of utmost importance. Two human cases due to zoonoticA(H5N1) and A(H9N2) avian influenza virus infection were reportedduring the reporting period. The risk for the general population as well as travel-related imported human cases are assessed as very low.
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Rohaim MA, El Naggar RF, Madbouly Y, AbdelSabour MA, Ahmed KA, Munir M. Comparative infectivity and transmissibility studies of wild-bird and chicken-origin highly pathogenic avian influenza viruses H5N8 in chickens. Comp Immunol Microbiol Infect Dis 2020; 74:101594. [PMID: 33271478 DOI: 10.1016/j.cimid.2020.101594] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2020] [Revised: 11/04/2020] [Accepted: 11/17/2020] [Indexed: 02/06/2023]
Abstract
Despite the recent advances in avian influenza viruses surveillance and genomic data, fundamental questions concerning the ecology and evolution of these viruses remain elusive. In Egypt, H5N8 highly pathogenic avian influenza viruses (HPAIVs) are co-circulating simultaneously with HPAIVs of subtypes H5N1 and low-pathogenic avian influenza viruses (LPAIVs) of subtype H9N2 in both commercial and backyard poultry. In order to isolate AIVs from wild birds and to assess their potential in causing infection in commercial poultry, a total of thirty-four cloacal swab samples were collected from apparently healthy migratory wild birds (Anas acuta, Anas crecca, Rallus aquaticus, and Bubulcus ibis) from four Egyptian Governorates (Giza, Menoufia, Gharbia, and Dakahlia). Based on matrix (M) gene-targeting real-time reverse transcriptase PCR and subsequent genetic characterization, our results revealed two positive isolates (2/34) for H5N8 whereas no H5N1 and H9N2 subtypes were detected. Genetic characterization of the full-length haemagglutinin (HA) genes revealed the clustering of two reported isolates within genotype 5 of clade 2.3.4.4b. The potential of a wild bird-origin H5N8 virus isolated from a cattle egret for its transmission capability within and between chickens was investigated in compare to chicken origin H5N8 AIV. Chickens inoculated with cattle egret isolate showed varying clinical signs and detection of virus shedding. In contrast, the contact chickens showed less levels of virus secretion indicating efficient virus inter/intra-species transmission. These results demonstrated the possibility for spreading of wild bird origin H5N8 viruses between chicken. In conclusion, our study highlights the need for continuous and frequent monitoring of the genetic diversity of H5N8 AIVs in wild birds as well as commercial poultry sectors for better understanding and determining the genetic nature of these viruses, which is fundamental to predict any future threat through virus reassortment with the potential to threaten human and animal health. Likewise, an assessment of coverage and efficacy of different vaccines and or vaccination regimes in the field conditions should be reconsidered along with strict biosecurity measures.
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Affiliation(s)
- Mohammed A Rohaim
- Department of Virology, Faculty of Veterinary Medicine, Cairo University, 12211 Giza, Egypt
| | - Rania F El Naggar
- Department of Virology, Faculty of Veterinary Medicine, University of Sadat City, 32897 Sadat, Egypt
| | - Yehia Madbouly
- Veterinary Serum and Vaccine Research Institute, Abbassia, Cairo 11381, Agricultural Research Center (ARC), Egypt
| | - Mohammed A AbdelSabour
- Veterinary Serum and Vaccine Research Institute, Abbassia, Cairo 11381, Agricultural Research Center (ARC), Egypt
| | - Kawkab A Ahmed
- Department of Pathology, Faculty of Veterinary Medicine, Cairo University, 12211 Giza, Egypt
| | - Muhammad Munir
- Division of Biomedical and Life Science, Lancaster University, LA1 4YG Lancaster, Lancashire, UK.
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Adlhoch C, Fusaro A, Gonzales JL, Kuiken T, Marangon S, Niqueux É, Staubach C, Smietanka K, Terregino C, Van der Stede Y, Aznar I, Baldinelli F. Avian influenza overview - update on 19 November 2020, EU/EEA and the UK. EFSA J 2020; 18:e06341. [PMID: 33281979 PMCID: PMC7684971 DOI: 10.2903/j.efsa.2020.6341] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Since 16 October 2020, outbreaks ofhighly pathogenic avian influenza (HPAI) viruseshavebeen reported inseveral EU/EEAcountries -Belgium, Denmark, France, Germany, Ireland, the Netherlands, and Swedenas well asin the United Kingdom.As of 19 November,12pm, 302 HPAI A(H5) detections have been reported, with the majority of the detections referring to wild birds (n=281), and a few related to outbreaks in poultry (n=18) and captive birds (n=3). Most of the detections in wild birds were in wild waterbirds,being barnacle goose the most affected species (n=110), followed by greylag goose (n=47), Eurasian wigeon (n=32),mallard (n=14), and common buzzard (n=13).ThreeHPAI virus subtypes were identified, A(H5N8), A(H5N5) and A(H5N1), with A(H5N8) being the most reported subtype (n=284). Phylogenetic analysis indicated that the viruses evolved from a single progenitor virus thatwent through multiple reassortment events. Based on the ongoing autumn migration of wild waterbirds to their wintering areas in Europe, there is a continued risk of further introduction of HPAI A(H5) viruses into Europe. Furthermore, given the expected movements of both migratory, and resident wild birds in Europe during winter, there is a high risk of further spread of HPAI A(H5) viruses within Europe. No genetic markers indicating adaptation to mammals have been identified in the viruses analysed so far,andno human infection due to avian influenza viruses detected in the recent outbreakshas been reported. For that reason,the risk to the general population remains very low.However,following the precautionary principle, people should avoid touching sick or dead birds unprotected to minimise any potential risk.
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Adlhoch C, Fusaro A, Kuiken T, Niqueux É, Staubach C, Terregino C, Muñoz Guajardo I, Baldinelli F. Avian influenza overview May - August 2020. EFSA J 2020; 18:e06270. [PMID: 33281980 PMCID: PMC7525800 DOI: 10.2903/j.efsa.2020.6270] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Between 16 May and 15 August 2020, seven highly pathogenic avian influenza (HPAI) A(H5N8) virus outbreaks were reported in Europe in poultry, with one outbreak reported in Bulgaria(n=1) andsix in Hungary (n=6) and one low pathogenic avian influenza (LPAI) A(H5N3) virus outbreak was reported in poultry in Italy. All six outbreaks detected in Hungary were secondary outbreaks and seem to be the tail end of the HPAI A(H5N8) epidemic that wasobserved in poultry over the winter and spring in central Europe from December 2019 (n=334).Genetic analysis of the HPAI A(H5N8) viruses isolated during this reporting period from Bulgaria and Hungary did not identify any major changes compared tothe viruses collected in the respective countries during the first months of 2020. This suggests a persistence of the virus in the two countries rather than new introductions via infectedwild birds. HPAI A(H5N8) virus has been detected in poultry and wild birds in western Russia within the reporting period, and as of the middle of September also in Kazakhstan. The presence of HPAI virus in western Russiaand in north Kazakhstan,spatially associated with autumnmigration routes of wild waterbirds, is of concern due to the possible spread of the virus via wild birds migrating to the EU.It is highly recommended thatMember States take appropriate measures to promptly detect suspected cases of HPAI, including increasing biosecurity measures. According to past experiences (2005-2006 and 2016-2017 epidemic waves), the northern and eastern European areas might be at higher risk of virus introduction in the coming autumn-winter seasonand should be the key regions where prompt response measures to early detect the virusshould be set up. One human case due to A(H9N2) avian influenza virus infection was reported during the reporting period.
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Adlhoch C, Fusaro A, Kuiken T, Smietanka K, Staubach C, Guajardo M, Baldinelli F. Avian influenza overview August - November2019. EFSA J 2020; 17:e05988. [PMID: 32626216 PMCID: PMC7008850 DOI: 10.2903/j.efsa.2019.5988] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Between 16 August and 15 November 2019, one low pathogenic avian influenza (LPAI) A(H5) outbreak in poultry in France was reported in Europe. Genetic characterisation reveals that the virusclusterswith Eurasian LPAI viruses. No highly pathogenic avian influenza (HPAI) outbreaks in birds were notified in Europe in the relevant period for this report. HPAI A(H5N6) viruswas identified in chickens in Nigeria, this isthe first report of HPAI A(H5N6) from the African continent.FewerHPAI outbreaks in Asia and Africa were reported during the time period for this report compared with the previous reporting period. Apart from the long‐term epidemic of HPAI A(H5N2)in Taiwan, only six HPAI outbreakswere reported in domestic birds from Nepal, South Africa and Taiwan. Furthermore, no HPAI detections fromwild birds were reported worldwide in the relevant time period forthis report.Even if the risk of incursion of HPAI from wild birds into poultryestablishments in Europe is currently assessed as low, it is important to maintain passive surveillance activities. The focus should be on wild bird species that are in the revised list of target species in order to detect any incursion of HPAI virus early and initiate a warning.Despite the decrease in the number of avian influenza outbreaks over recent months, it is important to maintain a high alert level andhigh standard of biosecurity onpoultry establishments.In Europe, no human infections due toHPAI viruses detected in wild bird or poultry outbreaks, have been reported. The risk of zoonotic transmission to the general public in Europe is considered to be very low.
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Adlhoch C, Fusaro A, Kuiken T, Niqueux E, Staubach C, Terregino C, Guajardo IM, Baldinelli F. Avian influenza overview February - May 2020. EFSA J 2020; 18:e06194. [PMID: 32874346 PMCID: PMC7448026 DOI: 10.2903/j.efsa.2020.6194] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Between 16 February and 15 May 2020, 290highly pathogenic avian influenza (HPAI) A(H5) virus outbreakswere reported in Europe in poultry (n=287), captive birds (n=2) and wild birds (n=1)in Bulgaria, Czechia,Germany,Hungary andPolandand two low pathogenic avian influenza (LPAI) A(H7N1) virus outbreaks were reported in poultry in Italy. 258 of 287 poultry outbreaks detected in Europe were secondary outbreaks, suggesting that in the large majoryty of cases the spread of the virus was not due to wild birds.Allthe HPAI outbreaks were A(H5N8) apart from three,which were reported as A(H5N2) from Bulgaria. Genetic analysis of the HPAI A(H5N8) viruses isolated from the eastern and central European countries indicates that this is a reassortant between HPAI A(H5N8) viruses from Africa and LPAI viruses from Eurasia. Two distict subtypes were identified in Bulgaria, a novel reassortant A(H5N2) and A(H5N8) that is persisting in the country since 2016. There could be several reasons why only very few HPAI cases were detected in wild birds in this 2019-2020 epidemic season and a better knowledge of wild bird movements and virus-host interaction (e.g. susceptibility of the hosts to this virus) could help to understand the reasons for poor detection of HPAI infected wild birds. In comparison with the last reporting period, a decreasing number of HPAI A(H5)-affected countries and outbreaks were reported from outside Europe. However, there is considerable uncertainty regarding the current epidemiological situation in many countries out of Europe. Four human cases due to A(H9N2) virus infection were reported during the reporting period from China.
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Schreuder J, Manders TTM, Elbers ARW, van der Spek AN, Bouwstra RJ, Stegeman JA, Velkers FC. Highly pathogenic avian influenza subtype H5Nx clade 2.3.4.4 outbreaks in Dutch poultry farms, 2014-2018: Clinical signs and mortality. Transbound Emerg Dis 2020; 68:88-97. [PMID: 32418364 PMCID: PMC8048556 DOI: 10.1111/tbed.13597] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 03/03/2020] [Accepted: 04/17/2020] [Indexed: 12/18/2022]
Abstract
In recent years, different subtypes of highly pathogenic avian influenza (HPAI) viruses caused outbreaks in several poultry types worldwide. Early detection of HPAI virus infection is crucial to reduce virus spread. Previously, the use of a mortality ratio threshold to expedite notification of suspicion in layer farms was proposed. The purpose of this study was to describe the clinical signs reported in the early stages of HPAI H5N8 and H5N6 outbreaks on chicken and Pekin duck farms between 2014 and 2018 in the Netherlands and compare them with the onset of an increased mortality ratio (MR). Data on daily mortality and clinical signs from nine egg‐producing chicken farms and seven Pekin duck farms infected with HPAI H5N8 (2014 and 2016) and H5N6 (2017–2018) in the Netherlands were analysed. In 12 out of 15 outbreaks for which a MR was available, MR increase preceded or coincided with the first observation of clinical signs by the farmer. In one chicken and two Pekin duck outbreaks, clinical signs were observed prior to MR increase. On all farms, veterinarians observed clinical signs of general disease. Nervous or locomotor signs were reported in all Pekin duck outbreaks, but only in two chicken outbreaks. Other clinical signs were observed less frequently in both chickens and Pekin ducks. Compared to veterinarians, farmers observed and reported clinical signs, especially respiratory and gastrointestinal signs, less frequently. This case series suggests that a MR with a set threshold could be an objective parameter to detect HPAI infection on chicken and Pekin duck farms at an early stage. Observation of clinical signs may provide additional indication for farmers and veterinarians for notifying a clinical suspicion of HPAI infection. Further assessment and validation of a MR threshold in Pekin ducks are important as it could serve as an important tool in HPAI surveillance programs.
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Affiliation(s)
- Janneke Schreuder
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Thijs T M Manders
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Armin R W Elbers
- Department of Bacteriology and Epidemiology, Wageningen Bioveterinary Research, Lelystad, the Netherlands
| | - Arco N van der Spek
- Netherlands Food and Consumer Product Safety Authority (NVWA), Utrecht, the Netherlands
| | | | - J Arjan Stegeman
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Francisca C Velkers
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
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Reid SM, Núñez A, Seekings AH, Thomas SS, Slomka MJ, Mahmood S, Clark JR, Banks J, Brookes SM, Brown IH. Two Single Incursions of H7N7 and H5N1 Low Pathogenicity Avian Influenza in U.K. Broiler Breeders During 2015 and 2016. Avian Dis 2020; 63:181-192. [PMID: 31131576 DOI: 10.1637/11898-051418-reg.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 12/02/2018] [Indexed: 11/05/2022]
Abstract
Low pathogenicity (LP) avian influenza viruses (AIVs) have a natural reservoir in wild birds. These cause few (if any) overt clinical signs, but include H5 and H7 LPAIVs, which are notifiable in poultry. In the European Union, notifiable avian disease (NAD) demands laboratory confirmation with prompt statutory interventions to prevent dissemination of infection to multiple farms. Crucially, for H5 and H7 LPAIVs, movement restrictions and culling limit the further risk of mutation to the corresponding highly pathogenic (HP) H5 and H7 AIVs in gallinaceous poultry. An H7N7 LPAIV outbreak occurred during February 2015 at a broiler breeder chicken premise in England. Full genome sequencing suggested an avian origin closely related to contemporary European H7 LPAIV wild bird strains with no correlates for human adaptation. However, a high similarity of PB2, PB1, and NA genes with H10N7 viruses from European seals during 2014 was observed. An H5N1 LPAIV outbreak during January 2016 affecting broiler breeder chickens in Scotland resulted in rapid within-farm spread. An interesting feature from this case was that although viral tropism occurred in heart and kidney endothelial cells, suggesting HPAIV infection, the H5N1 virus had the molecular cleavage site signature of an LPAIV belonging to an indigenous European H5 lineage. There was no genetic evidence for human adaptation or antiviral drug resistance. The source of the infection was also likely to be via indirect contact with wild birds mediated via fomite spread from the nearby environment. Both LPAIV outbreaks were preceded by local flooding events that attracted wild waterfowl to the premises. Prompt detection of both outbreaks highlighted the value of the "testing to exclude" scheme launched in the United Kingdom for commercial gallinaceous poultry in 2014 as an early warning surveillance mechanism for NAD.
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Affiliation(s)
- Scott M Reid
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom,
| | - Alejandro Núñez
- Department of Pathology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Amanda H Seekings
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Saumya S Thomas
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Marek J Slomka
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Sahar Mahmood
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Jane R Clark
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Jill Banks
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Sharon M Brookes
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
| | - Ian H Brown
- Department of Virology, Animal and Plant Health Agency-Weybridge, Woodham Lane, New Haw, Addlestone, Surrey, KT15 3NB, United Kingdom
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Adlhoch C, Fusaro A, Kuiken T, Niqueux E, Staubach C, Terregino C, Guajardo IM, Baldinelli F. Avian influenza overview November 2019- February2020. EFSA J 2020; 18:e06096. [PMID: 32874270 PMCID: PMC7448010 DOI: 10.2903/j.efsa.2020.6096] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Between 16 November 2019 and 15 February 2020, 36 highly pathogenic avian influenza (HPAI) A(H5N8) virus outbreakswere reported in Europe in poultry (n=34), captive birds (n=1) and wild birds (n=2), in Poland, Hungary, Slovakia, Romania, Germany, Czechiaand Ukraine,one HPAI outbreakcaused by a simultaneous infection with A(H5N2) and A(H5N8) was reported in poultry in Bulgaria, andtwo low pathogenic avian influenza (LPAI) A(H5) virus outbreaks were reported in poultryin the United Kingdom and in Denmark. Genomic characterisation of the HPAI A(H5N8) viruses suggests that they are reassortants of HPAI A(H5N8) viruses from Africa and LPAI viruses from Eurasia. It is likely that this reassortment occurred in wild migratory birds in Asia during the summer and then spread to eastern Europe with the autumnmigration. This is the first time that wild bird migration from Africa to Eurasia has been implicated in the long-distance spread of HPAI viruses to the EU. Given the late incursion of HPAI A(H5N8) virus into the EU in this winter season (first outbreak reported on 30 December 2019), its overall restriction to eastern Europe, and the approaching spring migration, the risk of the virus spreadingfurther in the west via wild birds is decreasing for the coming months. Genetic analysis of the HPAI A(H5N2) and A(H5N8) viruses detected in the Bulgarian outbreak reveals that these virusesare both related to the 2018-19 Bulgarian HPAI A(H5N8) viruses and not to the HPAI A(H5N8) viruses currently circulating in Europe.An increasing number of HPAI A(H5N1), A(H5N2), A(H5N5) and A(H5N6) virus outbreaks in poultry in Asia were reported during the time period for this report compared with the previous reporting period. Single outbreaks of HPAI A(H5N8) virus were notified by Saudi Arabia and South Africa. Furthermore, in contrast to the last report, HPAI virus-positive wild birds were reported from Israel and one of the key migration areas in northern China.Two human cases due to A(H9N2) virus infection were reported during the reporting period.
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Brouwer A, Gonzales J, Huneau A, Mulatti P, Kuiken T, Staubach C, Stegeman A, Antoniou SE, Baldinelli F, Van der Stede Y, Aznar I. Annual Report on surveillance for avian influenza in poultry and wild birds in Member States of the European Union in 2018. EFSA J 2019; 17:e05945. [PMID: 32626213 PMCID: PMC7008901 DOI: 10.2903/j.efsa.2019.5945] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Avian influenza (AI) is a viral infectious disease that affects all species of domestic and wild birds. The viruses causing this disease can be of high (HPAI) or low (LPAI) pathogenicity and represent a continuous threat to poultry in Europe. Council Directive 2005/94/EC requests EU Member States (MSs) to carry out surveillance in poultry and wild birds and notify the results to the responsible authority. Therefore, MSs and Switzerland have implemented surveillance programmes to yearly monitor incursions of AI viruses in poultry and wild birds. EFSA received a mandate from the European Commission, to collate, validate, analyse and summarise in an annual report the data resulting from the avian influenza surveillance programmes. This is the first report produced under this mandate summarising the results of the surveillance activities carried out in poultry and wild birds in 2018. Overall 18,596 poultry establishments were sampled, of which 43 were seropositive for H5 AI and two for H7 AI. Seropositive establishments were found in 11 MSs, with the highest percentage of seropositive establishments being found in waterfowl gamebird, and geese and duck breeding establishments. A total of 9,145 dead/moribund wild birds were sampled, with 163 birds testing positive to HPAI virus H5N6. The infected birds were reported by eight MSs and were mostly found between January and April 2018. In this report, the wild bird species affected with HPAI are described and the strategy of targeted sampling is assessed. The crude odds ratio of HPAI detection as a function of the target species (species belonging to the list of target species versus species not belonging to the target list) is presented. The surveillance findings for poultry and wild birds for 2018 are also discussed in relation to findings from previous years and current knowledge on the epidemiology of AI in Europe.
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Adlhoch C, Kuiken T, Monne I, Mulatti P, Smietanka K, Staubach C, Guajardo IM, Baldinelli F. Avian influenza overview November 2018 - February 2019. EFSA J 2019; 17:e05664. [PMID: 32626274 PMCID: PMC7009136 DOI: 10.2903/j.efsa.2019.5664] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
No human infections due to highly pathogenic avian influenza (HPAI) A(H5N8) or A(H5N6) viruses ‐ detected in wild birds and poultry outbreaks in Europe ‐ have been reported so far and the risk of zoonotic transmission to the general public in Europe is considered very low. Between 16 November 2018 and 15 February 2019, two HPAI A(H5N8) outbreaks in poultry establishments in Bulgaria, two HPAI A(H5N6) outbreaks in wild birds in Denmark and one low pathogenic avian influenza (LPAI) A(H5N3) in captive birds in the Netherlands were reported in the European Union (EU). Genetic characterisation of the HPAI A(H5N6) viruses reveals that they cluster with the A(H5N6) viruses that have been circulating in Europe since December 2017. The wild bird species involved were birds of prey and were likely infected due to hunting or scavenging infected wild waterfowl. However, HPAI virus was not detected in other wild birds during this period. Outside the EU, two HPAI outbreaks were reported in poultry during the reporting period from western Russia. Sequence information on an HPAI A(H5N6) virus found in a common gull in western Russia in October 2018 suggests that the virus clusters within clade 2.3.4.4c and is closely related to viruses that transmitted zoonotically in China. An increasing number of outbreaks in poultry and wild birds in Asia, Africa and the Middle East was observed during the time period for this report. Currently there is no evidence of a new HPAI virus incursion from Asia into Europe. However, passive surveillance systems may not be sensitive enough if the prevalence or case fatality in wild birds is very low. Nevertheless, it is important to encourage and maintain a certain level of passive surveillance in Europe testing single sick or dead wild birds and birds of prey as they may be sensitive sentinel species for the presence of HPAI virus in the environment. A well‐targeted active surveillance might complement passive surveillance to collect information on HPAI infectious status of apparently healthy wild bird populations.
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Gonzales JL, Roberts H, Smietanka K, Baldinelli F, Ortiz-Pelaez A, Verdonck F. Assessment of low pathogenic avian influenza virus transmission via raw poultry meat and raw table eggs. EFSA J 2018; 16:e05431. [PMID: 32625713 PMCID: PMC7009628 DOI: 10.2903/j.efsa.2018.5431] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
A rapid qualitative assessment has been done by performing a theoretical analysis on the transmission of low pathogenic avian influenza (LPAI) via fresh meat from poultry reared or kept in captivity for the production of meat (raw poultry meat) or raw table eggs. A predetermined transmission pathway followed a number of steps from a commercial or non-commercial poultry establishment within the EU exposed to LPAI virus (LPAIV) to the onward virus transmission to animals and humans. The combined probability of exposure and subsequent LPAIV infection via raw poultry meat containing LPAIV is negligible for commercial poultry and humans exposed via consumption whereas it is very unlikely for non-commercial poultry, wild birds and humans exposed via handling and manipulation. The probability of LPAIV transmission from an individual infected via raw poultry meat containing LPAIV is negligible for commercial poultry and humans, whereas it is very unlikely for non-commercial poultry and wild birds. The combined probability of exposure and subsequent LPAIV infection via raw table eggs containing LPAIV is negligible for commercial poultry and humans and extremely unlikely to negligible for non-commercial poultry and wild birds. The probability of LPAIV transmission from an individual infected via raw table eggs containing LPAIV is negligible for commercial poultry and humans and very unlikely to negligible for non-commercial poultry and wild birds. Although the presence of LPAIV in raw poultry meat and table eggs is very unlikely to negligible, there is in general a high level of uncertainty on the estimation of the subsequent probabilities of key steps of the transmission pathways for poultry and wild birds, mainly due to the limited number of studies available, for instance on the viral load required to infect a bird via raw poultry meat or raw table eggs containing LPAIV.
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Adlhoch C, Kuiken T, Mulatti P, Smietanka K, Staubach C, Muñoz Guajardo I, Amato L, Baldinelli F. Avian influenza overview May - August 2018. EFSA J 2018; 16:e05430. [PMID: 32626052 PMCID: PMC7009402 DOI: 10.2903/j.efsa.2018.5430] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Between 16 May and 15 August 2018, three highly pathogenic avian influenza (HPAI) A(H5N8) outbreaks in poultry establishments and three HPAI A(H5N6) outbreaks in wild birds were reported in Europe. Three low pathogenic avian influenza (LPAI) outbreaks were reported in three Member States. Few HPAI and LPAI bird cases have been detected in this period of the year, in accordance with the seasonal expected pattern of LPAI and HPAI. There is no evidence to date that HPAI A(H5N8) and A(H5N6) viruses circulating in Europe have caused any human infections. The risk of zoonotic transmission to the general public in Europe is considered to be very low. Several HPAI outbreaks in poultry were reported during this period from Russia. The presence of the A(H5N2) and A(H5N8) viruses in parts of Russia connected with fall migration routes of wild birds is of concern for possible introduction and spread with wild birds migrating to the EU. Although few AI outbreaks were observed in Africa, Asia and the Middle East during the reporting period, the probability of AI virus introductions from non‐EU countries via wild birds particularly via the north‐eastern route from Russia is increasing, as the fall migration of wild birds will start in the coming weeks. Further, the lower temperatures in autumn and winter may facilitate the environmental survival of avian influenza viruses potentially introduced to Europe.
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Adlhoch C, Brouwer A, Kuiken T, Mulatti P, Smietanka K, Staubach C, Muñoz Guajardo I, Verdonck F, Amato L, Baldinelli F. Avian influenza overview February - May 2018. EFSA J 2018; 16:e05358. [PMID: 32625951 PMCID: PMC7009712 DOI: 10.2903/j.efsa.2018.5358] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Between 16 February and 15 May 2018, three highly pathogenic avian influenza (HPAI) A(H5N6) and 11 HPAI A(H5N8) outbreaks in poultry holdings, one HPAI A(H5N6) and one HPAI A(H5N8) outbreak in captive birds, and 55 HPAI A(H5N6) wild bird events were reported in Europe. There is no evidence to date that HPAI A(H5N6) viruses circulating in Europe are associated with clades infecting humans. Fewer HPAI wild bird cases have been detected than during the same period of previous year. Most of mortality events among wild birds involved single birds and species listed in the revised list of target species for passive surveillance. Raptor species constitute 74% of the HPAI‐infected wild birds found dead. Those raptor species probably became infected by hunting or scavenging HPAI virus‐positive birds, and so raptor cases may predominate later in the course of an HPAI epidemic. Despite the important HPAI virus incursion via wild birds there have been few associated HPAI A(H5N6) outbreaks in poultry. Fifteen low pathogenic avian influenza (LPAI) outbreaks were reported in three Member States. The risk of zoonotic transmission to the general public in Europe is considered to be very low. The situation in Africa and the Middle East should be closely monitored with regards to HPAI A(H5N1) and A(H5N8). Uncontrolled spread of the virus and subsequent further genetic evolution in regions geographically connected to Europe may increase uncertainty and the risk for further dissemination of virus. Long‐distance migrating wild birds from southern Africa, e.g. the common tern (Sterna hirundo), may be included in targeted active surveillance schemes at a few priority locations in Europe in order to detect HPAI A(H5)‐infected migrating birds early. However, the risk of HPAI introduction from non‐EU countries via migratory wild birds to Europe is still considered to be much lower for wild birds crossing the southern borders than for those crossing the north‐eastern borders.
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Adlhoch C, Brouwer A, Kuiken T, Mulatti P, Smietanka K, Staubach C, Willeberg P, Barrucci F, Verdonck F, Amato L, Baldinelli F. Avian influenza overview November 2017 - February 2018. EFSA J 2018; 16:e05240. [PMID: 32625858 PMCID: PMC7009675 DOI: 10.2903/j.efsa.2018.5240] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Between 16 November 2017 and 15 February 2018, one highly pathogenic avian influenza (HPAI) A(H5N6) and five HPAI A(H5N8) outbreaks in poultry holdings, two HPAI A(H5N6) outbreaks in captive birds and 22 HPAI A(H5N6) wild bird events were reported within Europe. There is a lower incursion of HPAI A(H5N6) in poultry compared to HPAI A(H5N8). There is no evidence to date that HPAI A(H5N6) viruses circulating in Europe are associated with clades infecting humans. Clinical signs in ducks infected with HPAI A(H5N8) seemed to be decreasing, based on reports from Bulgaria. However, HPAI A(H5N8) is still present in Europe and is widespread in neighbouring areas. The majority of mortality events of wild birds from HPAIV A(H5) in this three‐month period involved single birds. This indicates that the investigation of events involving single dead birds of target species is important for comprehensive passive surveillance for HPAI A(H5). Moreover, 20 low pathogenic avian influenza (LPAI) outbreaks were reported in three Member States. The risk of zoonotic transmission to the general public in Europe is considered to be very low. The first human case due to avian influenza A(H7N4) was notified in China underlining the threat that newly emerging avian influenza viruses pose for transmission to humans. Close monitoring is required of the situation in Africa and the Middle East with regards to HPAI A(H5N1) and A(H5N8). Uncontrolled spread of virus and subsequent further genetic evolution in regions geographically connected to Europe may increase uncertainty and risk for further dissemination of virus. The risk of HPAI introduction from Third countries via migratory wild birds to Europe is still considered much lower for wild birds crossing the southern borders compared to birds crossing the north‐eastern borders, whereas the introduction via trade is still very to extremely unlikely.
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Brown I, Kuiken T, Mulatti P, Smietanka K, Staubach C, Stroud D, Therkildsen OR, Willeberg P, Baldinelli F, Verdonck F, Adlhoch C. Avian influenza overview September - November 2017. EFSA J 2017; 15:e05141. [PMID: 32625395 PMCID: PMC7010192 DOI: 10.2903/j.efsa.2017.5141] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Between 1 September and 15 November 2017, 48 A(H5N8) highly pathogenic avian influenza (HPAI) outbreaks in poultry holdings and 9 H5 HPAI wild bird events were reported within Europe. A second epidemic HPAI A(H5N8) wave started in Italy on the third week of July and is still ongoing on 15 November 2017. The Italian epidemiological investigations indicated that sharing of vehicles, sharing of personnel and close proximity to infected holdings are the more likely sources of secondary spread in a densely populated poultry area. Despite the ongoing human exposures to infected poultry during the outbreaks, no transmission to humans has been identified in the EU. The report includes an update of the list of wild bird target species for passive surveillance activities that is based on reported AI‐infected wild birds since 2006. The purpose of this list is to provide information on which bird species to focus in order to achieve the most effective testing of dead birds for detection of H5 HPAI viruses. Monitoring the avian influenza situation in other continents revealed the same risks as in the previous report (October 2016‐August 2017): the recent human case of HPAI A(H5N6) in China underlines the continuing threat of this avian influenza virus to human health and possible introduction via migratory wild birds into Europe. Close monitoring is required of the situation in Africa with regards to HPAI of the subtypes A(H5N1) and A(H5N8), given the rapidity of the evolution and the uncertainty on the geographical distribution of these viruses. Interactions between EFSA and member states have taken place to initiate discussions on improving the quality of data collections and to find a step‐wise approach to exchange relevant (denominator) data without causing an additional resource burden.
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