{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T05:55:17Z","timestamp":1776318917630,"version":"3.50.1"},"reference-count":41,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T00:00:00Z","timestamp":1776297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Introduction<\/jats:title>\n                    <jats:p>The persistent circulation of influenza viruses following the COVID-19 pandemic remains a major public health concern, yet local genomic epidemiology in pediatric populations is not well-defined.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>In 2024, we collected 490 influenza antigen-positive specimens from a pediatric hospital in Qidong, eastern China, and performed influenza genome enrichment-based whole-genome sequencing, yielding 425 genomes (86.73%) with at least hemagglutinin (HA) and neuraminidase (NA) segments.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>A\/H1N1 (45.41%), A\/H3N2 (18.35%), and B\/Victoria (36.24%) co-circulated, with two activity peaks in January and December. Phylogenetic analysis assigned these viruses to clades 6B.1A.5a.2a (A\/H1N1), 3C.2a1b.2a.2a.3a.1 (A\/H3N2), and V1A.3a.2 (B\/Victoria). Positively selected sites in HA included lineage-specific residues such as position 210 in B\/Victoria and positions 187 and 372 in A\/H3N2. The oseltamivir resistance marker NA-H275Y was detected in 7\/193 (3.65%) A\/H1N1 strains, whereas no detected resistance to RNA polymerase inhibitors.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Discussion<\/jats:title>\n                    <jats:p>These findings highlight the co-circulation patterns, genetic diversity, and antiviral susceptibility profile of influenza viruses in a pediatric population in eastern China, supporting the importance of sustained genomic surveillance to guide local prevention strategies and clinical management.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fmicb.2026.1799181","type":"journal-article","created":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T05:25:13Z","timestamp":1776317113000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Molecular epidemiology and genetic characteristics of influenza viruses in a local pediatric population of eastern China, 2024"],"prefix":"10.3389","volume":"17","author":[{"given":"Xiaoqing","family":"Sun","sequence":"first","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Shanghai Medical College, Fudan University","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiang","family":"Li","sequence":"additional","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Shanghai Medical College, Fudan University","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haiyan","family":"Chen","sequence":"additional","affiliation":[{"name":"Pediatric Department, Children's Hospital of Fudan University at Qidong","place":["Nantong, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tianyuan","family":"Lu","sequence":"additional","affiliation":[{"name":"Pediatric Department, Children's Hospital of Fudan University at Qidong","place":["Nantong, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhaoqi","family":"Fang","sequence":"additional","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Shanghai Medical College, Fudan University","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Danyang","family":"Chen","sequence":"additional","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Shanghai Medical College, Fudan University","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Qiliang","family":"Cai","sequence":"additional","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Shanghai Medical College, Fudan University","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Shen","sequence":"additional","affiliation":[{"name":"Pediatric Department, Children's Hospital of Fudan University at Qidong","place":["Nantong, China"]},{"name":"Infectious Disease Department, Children's Hospital of Fudan University, National Children's Medical Center","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Youhua","family":"Xie","sequence":"additional","affiliation":[{"name":"Key Laboratory of Medical Molecular Virology (MOE\/NHC\/CAMS), Shanghai Institute of Infectious Disease and Biosecurity, Shanghai Frontiers Science Center of Pathogenic Microorganisms and Infection, School of Basic Medical Sciences, Shanghai Medical College, Fudan University","place":["Shanghai, China"]}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,16]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"e2175","DOI":"10.1002\/rmv.2175","article-title":"Fitness of Influenza A and B viruses with reduced susceptibility to baloxavir: a mini-review","volume":"31","author":"Abed","year":"2021","journal-title":"Rev. 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