{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T12:25:03Z","timestamp":1773145503397,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,18]],"date-time":"2021-01-18T00:00:00Z","timestamp":1610928000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100015691","name":"Division of Microbiology and Infectious Diseases, National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["HHSN272201400006C and HHSN272201400005C"],"award-info":[{"award-number":["HHSN272201400006C and HHSN272201400005C"]}],"id":[{"id":"10.13039\/100015691","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Influenza A Viruses (IAV) in domestic swine (IAV-S) are associated with sporadic zoonotic transmission at the human\u2013animal interface. Previous pandemic IAVs originated from animals, which emphasizes the importance of characterizing human immunity against the increasingly diverse IAV-S. We analyzed serum samples from healthy human donors (n = 153) using hemagglutination-inhibition (HAI) assay to assess existing serologic protection against a panel of contemporary IAV-S isolated from swine in the United States (n = 11). Age-specific seroprotection rates (SPR), which are the proportion of individuals with HAI \u2265 1:40, corresponded with lower or moderate pandemic risk classifications for the multiple IAV-S examined (one H1-\u03b41, one H1-\u03b42, three H3-IVA, one H3-IVB, one H3-IVF). Individuals born between 2004 and 2013 had SPRs of 0% for the five classified H3 subtype IAV-S, indicating youth may be particularly predisposed to infection with these viruses. Expansion of existing immunologic gaps over time could increase likelihood of future IAV-S spillover to humans and facilitate subsequent sustained human-to-human transmission resulting in disease outbreaks with pandemic potential.<\/jats:p>","DOI":"10.3390\/v13010127","type":"journal-article","created":{"date-parts":[[2021,1,21]],"date-time":"2021-01-21T02:36:05Z","timestamp":1611196565000},"page":"127","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Gaps in Serologic Immunity against Contemporary Swine-Origin Influenza A Viruses among Healthy Individuals in the United States"],"prefix":"10.3390","volume":"13","author":[{"given":"Joshua N.","family":"Lorbach","sequence":"first","affiliation":[{"name":"Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Theresa","family":"Fitzgerald","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14627, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Carolyn","family":"Nolan","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14627, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2705-4805","authenticated-orcid":false,"given":"Jacqueline M.","family":"Nolting","sequence":"additional","affiliation":[{"name":"Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"John J.","family":"Treanor","sequence":"additional","affiliation":[{"name":"Department of Medicine, University of Rochester Medical Center, Rochester, NY 14627, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9435-8673","authenticated-orcid":false,"given":"David J.","family":"Topham","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Immunology, University of Rochester Medical Center, Rochester, NY 14627, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0738-8453","authenticated-orcid":false,"given":"Andrew S.","family":"Bowman","sequence":"additional","affiliation":[{"name":"Department of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, OH 43210, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"591","DOI":"10.1038\/nrmicro1208","article-title":"Influenza: Lessons from past pandemics, warnings from current incidents","volume":"3","author":"Horimoto","year":"2005","journal-title":"Nat. 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