{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,2]],"date-time":"2026-09-02T03:48:54Z","timestamp":1788320934926,"version":"build-2803163510"},"reference-count":40,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2026,2,5]],"date-time":"2026-02-05T00:00:00Z","timestamp":1770249600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Prevention and Control of Emerging and Major Infectious Diseases-National Science and Technology Major Project","award":["2025ZD01901802"],"award-info":[{"award-number":["2025ZD01901802"]}]},{"DOI":"10.13039\/501100003819","name":"Natural Science Foundation of Hubei Province","doi-asserted-by":"crossref","award":["2021CFA012"],"award-info":[{"award-number":["2021CFA012"]}],"id":[{"id":"10.13039\/501100003819","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100017958","name":"Health Commission of Hubei Province","doi-asserted-by":"crossref","award":["WJ2021M262"],"award-info":[{"award-number":["WJ2021M262"]}],"id":[{"id":"10.13039\/100017958","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Medical Research Project of Wuhan Health Commission","award":["WX23A90"],"award-info":[{"award-number":["WX23A90"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Viruses"],"abstract":"<jats:p>Despite the persistent global threat of seasonal influenza viruses such as A(H1N1)pdm09 and A\/H3N2, their epidemiological and genetic characteristics in China following the implementation of COVID-19 non-pharmaceutical interventions (NPIs) remain poorly characterized. Between September 2020 and December 2023, we conducted an integrated epidemiological and genomic analysis of influenza A viruses in children in Wuhan. The overall positivity rate for influenza A virus was markedly low at 3.43% (109\/3171), reflecting a profound suppression of circulation during the pandemic. Among genotyped positives, H1N1pdm09 was predominant (52.3%), followed by H3N2 (16.5%) and untypeable strains (32.1%). Preschool children showed the highest susceptibility. Phylogenetic analysis revealed that the circulating H1N1 strains (90%) belonged to clade 6B.1A.5a.2, clustering with viruses from Hong Kong and Pakistan. In contrast, H3N2 strains (76.92%) primarily fell into clade 3C.2a1b.2a.2b, closely related to contemporary strains from Europe and North America. Notably, we identified key hemagglutinin mutations associated with antigenic drift (e.g., R240Q in H1N1; E78G, R158G in H3N2) and neuraminidase mutations potentially conferring antiviral resistance (e.g., S247N in H1N1; S245N, a putative novel glycosylation site, in H3N2). Evidence of reassortment events was also detected, underscoring the continued genomic evolution of these viruses despite their low prevalence. Our findings demonstrate that genetically diverse and antigenically drifted influenza A viruses continued to circulate and evolve in Wuhan during the COVID-19 pandemic, albeit at dramatically reduced levels. This highlights the critical need for sustained genomic surveillance and timely updates of vaccine compositions to pre-empt the resurgence of influenza in the post-pandemic era.<\/jats:p>","DOI":"10.3390\/v18020210","type":"journal-article","created":{"date-parts":[[2026,2,5]],"date-time":"2026-02-05T15:24:19Z","timestamp":1770305059000},"page":"210","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Genomic Evolution of Influenza A(H1N1)pdm09 and A\/H3N2 Viruses Among Children in Wuhan, China, Spanning the COVID-19 Pandemic (2020\u20132023)"],"prefix":"10.3390","volume":"18","author":[{"given":"Muhammad Arif","family":"Rizwan","sequence":"first","affiliation":[{"name":"State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China"},{"name":"University of Chinese Academy of Sciences, Beijing 101409, China"},{"name":"Institute of Continuing Education & Extension, Cholistan University of Veterinary & Animal Sciences, Bahawalpur 63100, Pakistan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ying","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China"},{"name":"University of Chinese Academy of Sciences, Beijing 101409, China"},{"name":"Department of Respiratory Medicine, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"},{"name":"Pediatric Respiratory Disease Laboratory, Institute of Maternal and Child Health, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiaming","family":"Huang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China"},{"name":"University of Chinese Academy of Sciences, Beijing 101409, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4727-088X","authenticated-orcid":false,"given":"Haizhou","family":"Liu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Muhammad","family":"Noman","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China"},{"name":"University of Chinese Academy of Sciences, Beijing 101409, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9253-754X","authenticated-orcid":false,"given":"Ismaila Damilare","family":"Isiaka","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Virology and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China"},{"name":"University of Chinese Academy of Sciences, Beijing 101409, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hebin","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"},{"name":"Pediatric Respiratory Disease Laboratory, Institute of Maternal and Child Health, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wenqing","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"},{"name":"Pediatric Respiratory Disease Laboratory, Institute of Maternal and Child Health, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuehu","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"},{"name":"Pediatric Respiratory Disease Laboratory, Institute of Maternal and Child Health, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Huaying","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"},{"name":"Pediatric Respiratory Disease Laboratory, Institute of Maternal and Child Health, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuyi","family":"Xiao","sequence":"additional","affiliation":[{"name":"Department of Respiratory Medicine, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"},{"name":"Pediatric Respiratory Disease Laboratory, Institute of Maternal and Child Health, Wuhan Children\u2019s Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430014, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yi","family":"Yan","sequence":"additional","affiliation":[{"name":"Department of Respiratory 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