{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,14]],"date-time":"2026-10-14T00:59:46Z","timestamp":1791939586687,"version":"4.3.4"},"reference-count":39,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2024,12,22]],"date-time":"2024-12-22T00:00:00Z","timestamp":1734825600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Pennsylvania Game Commission","award":["75N93021C00016"],"award-info":[{"award-number":["75N93021C00016"]}]},{"name":"Richard King Mellon Foundation","award":["75N93021C00016"],"award-info":[{"award-number":["75N93021C00016"]}]},{"name":"National Institute of Allergy and Infectious Diseases","award":["75N93021C00016"],"award-info":[{"award-number":["75N93021C00016"]}]},{"name":"National Institutes of Health","award":["75N93021C00016"],"award-info":[{"award-number":["75N93021C00016"]}]},{"name":"Department of Health and Human Services","award":["75N93021C00016"],"award-info":[{"award-number":["75N93021C00016"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Animals"],"abstract":"<jats:p>The avian influenza virus is a global pathogen with significant health and economic implications. While primarily a pathogen of wild and domestic birds, recent outbreaks of the H5N1 highly pathogenic avian influenza virus (HPAIV) clade 2.3.4.4b have caused mortality in a wide variety of mammals, including members of the Canidae family, on multiple continents. Despite sporadic mortality events globally, the epidemiology and pathobiology of H5N1 HPAIV in wild canids remains poorly defined. During 2022\u20132024, 41 wild canid carcasses (diagnostic cases), including 23 red foxes and 18 gray foxes, were tested for the influenza A virus (IAV) via PCR, with five red fox kits testing positive (12%). Infected animals had variably severe encephalitis, pneumonia, and occasionally myocarditis associated with strong immunolabeling for IAV. Serum from 269 wild canids in Pennsylvania was tested for antibodies to IAV, including 133 samples collected prior to 2021 (pre-H5N1 HPAIV 2.3.4.4b introduction) and 136 collected after 2022 (post-H5N1 HPAIV 2.3.4.4b introduction). All samples collected prior to 2021 were seronegative for IAV. Two coyotes from 2024 were seropositive for IAV but were negative for antibodies to the H5 and N1 subtypes. Collectively, these data suggest that while sporadic H5N1 HPAIV infection and mortality can occur in wild canids, particularly juvenile red foxes, infection was limited in these outwardly healthy and opportunistically sampled animals. Future studies should utilize a risk-based approach to target sampling of wild canids at increased risk for H5N1 HPAIV infection, such as those around waterfowl habitats or spatially around wild bird or domestic animal outbreaks.<\/jats:p>","DOI":"10.3390\/ani14243700","type":"journal-article","created":{"date-parts":[[2024,12,23]],"date-time":"2024-12-23T08:16:07Z","timestamp":1734941767000},"page":"3700","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Surveillance of Highly Pathogenic Avian Influenza Virus in Wild Canids from Pennsylvania, USA"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9560-5621","authenticated-orcid":false,"given":"Kevin D.","family":"Niedringhaus","sequence":"first","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0006-6117-9042","authenticated-orcid":false,"given":"Taylor C.","family":"Chan","sequence":"additional","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ashley","family":"McDowell","sequence":"additional","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lauren","family":"Maxwell","sequence":"additional","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Madison","family":"Stevens","sequence":"additional","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lane","family":"Potts","sequence":"additional","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1049-6228","authenticated-orcid":false,"given":"Erica","family":"Miller","sequence":"additional","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eman","family":"Anis","sequence":"additional","affiliation":[{"name":"Wildlife Futures Program, School of Veterinary Medicine, University of Pennsylvania, Kennett Square, PA 19348, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyle Van","family":"Why","sequence":"additional","affiliation":[{"name":"United States Department of Agriculture, Animal and Plant Health Inspection Service, Wildlife Services, Harrisburg, PA 17106, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-4666-8711","authenticated-orcid":false,"given":"Thomas","family":"Keller","sequence":"additional","affiliation":[{"name":"The Pennsylvania Game Commission, Harrisburg, PA 17110, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David","family":"Stallknecht","sequence":"additional","affiliation":[{"name":"Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8087-3295","authenticated-orcid":false,"given":"Rebecca L.","family":"Poulson","sequence":"additional","affiliation":[{"name":"Southeastern Cooperative Wildlife Disease Study, College of Veterinary Medicine, University of Georgia, Athens, GA 30602, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaitlyn","family":"Bahrs","sequence":"additional","affiliation":[{"name":"Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9185-9288","authenticated-orcid":false,"given":"Justin D.","family":"Brown","sequence":"additional","affiliation":[{"name":"Department of Veterinary and Biomedical Sciences, Pennsylvania State University, University Park, PA 16802, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2024,12,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Antigua, K.J.C., Choi, W.-S., Baek, Y.H., and Song, M.-S. 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