{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:13:03Z","timestamp":1760058783837,"version":"build-2065373602"},"reference-count":45,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,4,28]],"date-time":"2025-04-28T00:00:00Z","timestamp":1745798400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Institute of Allergy and Infectious Diseases","award":["CEIRR 75N93021C00016","1241662"],"award-info":[{"award-number":["CEIRR 75N93021C00016","1241662"]}]},{"name":"Fondecyt","award":["CEIRR 75N93021C00016","1241662"],"award-info":[{"award-number":["CEIRR 75N93021C00016","1241662"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Educational farms provide students with hands-on experience in agricultural and animal practices. However, the close contact between humans and farm animals creates a significant interface for zoonotic disease transmission, yet research on infectious diseases in such settings remains limited. This study investigates the ongoing spillovers of human-origin influenza A virus (IAV) into swine at an educational farm in central Chile, describing IAV prevalence, outbreak dynamics, and the genomic characterization of detected strains. The Menesianos educational farm, located in Melipilla, central Chile, houses approximately 40 swine alongside other domestic animals, such as horses and cows. As part of an active IAV surveillance project, monthly nasal swab samples were collected from pigs between June 2019 and September 2023 for IAV detection via RT-qPCR targeting the M gene, with positive samples subsequently sequenced. During the study period, monthly IAV prevalence ranged from 0% to 52.5%, with a notable outbreak detected between May and June 2023. The outbreak lasted 5 weeks, peaking at 52.5% prevalence during week 3. Nine IAV strains were isolated over the study period, eight of which were obtained during weeks 2 and 3 of the outbreak. Phylogenetic analysis revealed that all strains were closely related to the pandemic H1N1 2009 influenza virus, with the closest related strains being those circulating in humans in Chile during the same years. These findings highlight the importance of conducting regular IAV surveillance on educational farms, where close interactions between animals and individuals\u2014particularly children and young people\u2014can facilitate viral spillovers and potential reverse zoonosis events.<\/jats:p>","DOI":"10.3390\/v17050635","type":"journal-article","created":{"date-parts":[[2025,5,2]],"date-time":"2025-05-02T11:35:13Z","timestamp":1746185713000},"page":"635","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Circulation and Spillover of pdmH1N1 Influenza A Virus at an Educational Swine Farm in Chile, 2019\u20132023"],"prefix":"10.3390","volume":"17","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9475-9629","authenticated-orcid":false,"given":"Soledad","family":"Ruiz","sequence":"first","affiliation":[{"name":"Escuela de Medicina Veterinaria, Facultad de Recursos Naturales y Medicina Veterinaria, Universidad Santo Tom\u00e1s, Santiago 8370003, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Constanza","family":"D\u00edaz-Gavidia","sequence":"additional","affiliation":[{"name":"Escuela de Medicina Veterinaria, Facultad de Medicina, Facultad de Ciencias Biol\u00f3gicas, y Facultad de Agronom\u00eda y Sistemas Naturales, Pontificia Universidad Cat\u00f3lica de Chile, Santiago 7820436, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda Antonieta","family":"Gonz\u00e1lez","sequence":"additional","affiliation":[{"name":"Escuela de Medicina Veterinaria, Facultad de Medicina, Facultad de Ciencias Biol\u00f3gicas, y Facultad de Agronom\u00eda y Sistemas Naturales, Pontificia Universidad Cat\u00f3lica de Chile, Santiago 7820436, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pablo","family":"Galdames","sequence":"additional","affiliation":[{"name":"Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820000, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Crist\u00f3bal","family":"Oyarz\u00fan","sequence":"additional","affiliation":[{"name":"Escuela de Medicina Veterinaria, Facultad de Medicina, Facultad de Ciencias Biol\u00f3gicas, y Facultad de Agronom\u00eda y Sistemas Naturales, Pontificia Universidad Cat\u00f3lica de Chile, Santiago 7820436, Chile"},{"name":"Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820000, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cecilia","family":"Baumberger","sequence":"additional","affiliation":[{"name":"Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820000, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Camila","family":"Rojas","sequence":"additional","affiliation":[{"name":"Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820000, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5609-2237","authenticated-orcid":false,"given":"Christopher","family":"Hamilton-West","sequence":"additional","affiliation":[{"name":"Departamento de Medicina Preventiva Animal, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santiago 8820000, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bridgett","family":"Sharp","sequence":"additional","affiliation":[{"name":"Host-Microbe Interactions, St. Jude Children\u2019s Research Hospital, Memphis, TN 38105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9880-8213","authenticated-orcid":false,"given":"Shaoyuan","family":"Tan","sequence":"additional","affiliation":[{"name":"Host-Microbe Interactions, St. Jude Children\u2019s Research Hospital, Memphis, TN 38105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2021-727X","authenticated-orcid":false,"given":"Stacey","family":"Schultz-Cherry","sequence":"additional","affiliation":[{"name":"Host-Microbe Interactions, St. Jude Children\u2019s Research Hospital, Memphis, TN 38105, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pedro","family":"Jimenez-Bluhm","sequence":"additional","affiliation":[{"name":"Escuela de Medicina Veterinaria, Facultad de Medicina, Facultad de Ciencias Biol\u00f3gicas, y Facultad de Agronom\u00eda y Sistemas Naturales, Pontificia Universidad Cat\u00f3lica de Chile, Santiago 7820436, Chile"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Chauhan, R.P., and Gordon, M.L. 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