{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,3]],"date-time":"2025-11-03T23:03:51Z","timestamp":1762211031870,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T00:00:00Z","timestamp":1636588800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["2015R1A6A1A03032236","2018M3A9H4055194"],"award-info":[{"award-number":["2015R1A6A1A03032236","2018M3A9H4055194"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Avian influenza virus (AIV) subtypes H5 and H7, possessing the ability to mutate spontaneously from low pathogenic (LP) to highly pathogenic (HP) variants, are major concerns for enormous socio-economic losses in the poultry industry, as well as for fatal human infections. Through antigenic drift and shift, genetic reassortments of the genotypes pose serious threats of increased virulence and pathogenicity leading to potential pandemics. In this study, we isolated the H7-subtype AIVs circulating in the Republic of Korea during 2018\u20132019, and perform detailed molecular analysis to study their circulation, evolution, and possible emergence as a zoonotic threat. Phylogenetic and nucleotide sequence analyses of these isolates revealed their distribution into two distinct clusters, with the HA gene sharing the highest nucleotide identity with either the A\/common teal\/Shanghai\/CM1216\/2017, isolated from wild birds in Shanghai, China, or the A\/duck\/Shimane\/2014, isolated from Japan. Mutations were found in HA (S138A (H3 numbering)), M1 (N30D and T215A), NS1 (P42S), PB2 (L89V), and PA (H266R and F277S) proteins\u2014the mutations had previously been reported to be related to mammalian adaptation and changes in the virulence of AIVs. Taken together, the results firmly put forth the demand for routine surveillance of AIVs in wild birds to prevent possible pandemics arising from reassortant AIVs.<\/jats:p>","DOI":"10.3390\/v13112260","type":"journal-article","created":{"date-parts":[[2021,11,11]],"date-time":"2021-11-11T23:07:21Z","timestamp":1636672041000},"page":"2260","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Molecular Analysis of the Avian H7 Influenza Viruses Circulating in South Korea during 2018\u20132019: Evolutionary Significance and Associated Zoonotic Threats"],"prefix":"10.3390","volume":"13","author":[{"given":"Bao Tuan","family":"Duong","sequence":"first","affiliation":[{"name":"Zoonosis Research Center, Department of Infection Biology, School of Medicine, Wonkwang University, Iksan 54538, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5608-6638","authenticated-orcid":false,"given":"Jyotiranjan","family":"Bal","sequence":"additional","affiliation":[{"name":"Zoonosis Research Center, Department of Infection Biology, School of Medicine, Wonkwang University, Iksan 54538, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7715-1390","authenticated-orcid":false,"given":"Haan Woo","family":"Sung","sequence":"additional","affiliation":[{"name":"College of Veterinary Medicine, Kangwon National University, Chuncheon-si 24341, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1406-1747","authenticated-orcid":false,"given":"Seon-Ju","family":"Yeo","sequence":"additional","affiliation":[{"name":"Department of Tropical Medicine and Parasitology, Seoul National University College of Medicine, Seoul 03080, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hyun","family":"Park","sequence":"additional","affiliation":[{"name":"Zoonosis Research Center, Department of Infection Biology, School of Medicine, Wonkwang University, Iksan 54538, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,11,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1817","DOI":"10.1098\/rstb.2001.0997","article-title":"Emergence of influenza A viruses","volume":"356","author":"Webby","year":"2001","journal-title":"Philos. 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