{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T05:14:31Z","timestamp":1787030071725,"version":"build-2736575974"},"reference-count":52,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2022,7,8]],"date-time":"2022-07-08T00:00:00Z","timestamp":1657238400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Veterinary Sciences"],"abstract":"<jats:p>Highly pathogenic avian influenza (HPAI, Gs\/Gd lineage) was introduced to Europe in 2005 and has since caused numerous outbreaks in birds. The 2020\u20132021 season was the hitherto most devastating when considering bird numbers and duration in Europe. Surveillance data, virologic results and epidemiologic investigations from the 2020\u20132021 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.<\/jats:p>","DOI":"10.3390\/vetsci9070344","type":"journal-article","created":{"date-parts":[[2022,7,11]],"date-time":"2022-07-11T00:06:21Z","timestamp":1657497981000},"page":"344","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":20,"title":["Highly Pathogenic Avian Influenza (HPAI H5Nx, Clade 2.3.4.4.b) in Poultry and Wild Birds in Sweden: Synopsis of the 2020\u20132021 Season"],"prefix":"10.3390","volume":"9","author":[{"given":"Malin","family":"Grant","sequence":"first","affiliation":[{"name":"Department of Disease Control and Epidemiology, National Veterinary Institute, 751 89 Uppsala, Sweden"},{"name":"Department of Clinical Sciences, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caroline","family":"Br\u00f6jer","sequence":"additional","affiliation":[{"name":"Department of Pathology and Wildlife Diseases, National Veterinary Institute, 751 89 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siamak","family":"Zohari","sequence":"additional","affiliation":[{"name":"Department of Microbiology, National Veterinary Institute, 751 89 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"N\u00f6remark","sequence":"additional","affiliation":[{"name":"Department of Disease Control and Epidemiology, National Veterinary Institute, 751 89 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Henrik","family":"Uhlhorn","sequence":"additional","affiliation":[{"name":"Department of Pathology and Wildlife Diseases, National Veterinary Institute, 751 89 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D\u00e9sir\u00e9e S.","family":"Jansson","sequence":"additional","affiliation":[{"name":"Department of Clinical Sciences, Swedish University of Agricultural Sciences, 750 07 Uppsala, Sweden"},{"name":"Department of Animal Health and Antimicrobial Strategies, National Veterinary Institute, 751 89 Uppsala, Sweden"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,7,8]]},"reference":[{"key":"ref_1","unstructured":"(2022, May 14). 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