{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T15:59:42Z","timestamp":1768665582202,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T00:00:00Z","timestamp":1768435200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["32270562"],"award-info":[{"award-number":["32270562"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"crossref","award":["ZR2022MC007"],"award-info":[{"award-number":["ZR2022MC007"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"crossref","award":["ZR2024MC172"],"award-info":[{"award-number":["ZR2024MC172"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"crossref","award":["ZR2023QC319"],"award-info":[{"award-number":["ZR2023QC319"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100007129","name":"Shandong Provincial Natural Science Foundation","doi-asserted-by":"crossref","award":["ZR2021MC119"],"award-info":[{"award-number":["ZR2021MC119"]}],"id":[{"id":"10.13039\/501100007129","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Influenza A viruses exhibit broad host tropism, infecting multiple species including humans, avian species, and swine. Swine influenza virus (SIV), while primarily circulating in porcine populations, demonstrates zoonotic potential with sporadic human infections. In this investigation, we identified two H1N1 subtype swine influenza A virus strains designated A\/swine\/China\/SD6591\/2019(H1N1) (abbreviated SD6591) and A\/swine\/China\/SD6592\/2019(H1N1) (abbreviated SD6592) in Shandong Province, China. The GenBank accession numbers of the SD6591 viral gene segments are PV464931-PV464938, and the GenBank accession numbers corresponding to each of the eight SD6592 viral gene segments are PV464939-PV464946. Phylogenetic and recombination analyses suggest potential evolutionary differences between the isolates. SD6591 displayed a unique triple-reassortant genotype: comparative nucleotide homology assessments demonstrated that the PB2, PB1, NP, NA, HA, and NEP genes shared the highest similarity with classical swine-origin H1N1 viruses. In contrast, SD6592 maintained genomic conservation with previously characterized H1N1 swine strains, although neither of these two isolates exhibited significant intrasegmental recombination events. Through comprehensive sequence analysis of these H1N1 SIVs, this study provides preliminary insights into their evolutionary history and underscores the persistent risk of cross-species transmission at the human\u2013swine interface. These findings establish an essential foundation for enhancing national SIV surveillance programs and informing evidence-based prevention strategies against emerging influenza threats.<\/jats:p>","DOI":"10.3390\/v18010117","type":"journal-article","created":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T14:35:38Z","timestamp":1768487738000},"page":"117","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Genetic Characterization and Evolutionary Insights of Novel H1N1 Swine Influenza Viruses Identified from Pigs in Shandong Province, China"],"prefix":"10.3390","volume":"18","author":[{"given":"Zhen","family":"Yuan","sequence":"first","affiliation":[{"name":"School of Biological Science and Technology, University of Jinan, Jinan 250022, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-1660-6458","authenticated-orcid":false,"given":"Ran","family":"Wei","sequence":"additional","affiliation":[{"name":"Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, China"},{"name":"Shandong Provincial Key Laboratory of Livestock and Poultry Breeding (PKL2024B15), Jinan 250100, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rui","family":"Shang","sequence":"additional","affiliation":[{"name":"College of Life Sciences, Shandong Normal University, Jinan 250014, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-7413-2754","authenticated-orcid":false,"given":"Huixia","family":"Zhang","sequence":"additional","affiliation":[{"name":"Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, China"},{"name":"Shandong Provincial Key Laboratory of Livestock and Poultry Breeding (PKL2024B15), Jinan 250100, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kaihui","family":"Cheng","sequence":"additional","affiliation":[{"name":"Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan 250100, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sisi","family":"Ma","sequence":"additional","affiliation":[{"name":"School of Animal Science and Technology, Ningxia University, Lanzhou 750021, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lei","family":"Zhou","sequence":"additional","affiliation":[{"name":"School of Biological Science and Technology, University of Jinan, Jinan 250022, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4588-8800","authenticated-orcid":false,"given":"Zhijun","family":"Yu","sequence":"additional","affiliation":[{"name":"School of Biological Science and Technology, University of Jinan, Jinan 250022, China"},{"name":"Poultry Institute, Shandong Academy of Agricultural Sciences, Jinan 250100, China"},{"name":"Shandong Provincial Key Laboratory of Livestock and Poultry Breeding (PKL2024B15), Jinan 250100, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2026,1,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"355","DOI":"10.1007\/s00018-024-05392-z","article-title":"Influenza A virus infection activates caspase-8 to enhance innate antiviral immunity by cleaving CYLD and blocking TAK1 and RIG-I deubiquitination","volume":"81","author":"Yu","year":"2024","journal-title":"Cell. 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