一起学校聚集性感染甲型H3N2流感病毒基因特征分析  

An Analysis of Genetic Characteristics of a School Cluster Infected with Influenza A(H3N2)Virus

作　　者：张涛[1] 邱超 张亮 ZHANG Tao;QIU Chao;ZHANG Liang(Zaozhuang Municipal Center for Disease Control and Prevention,Zaozhuang 277000,China)

机构地区：[1]枣庄市疾病预防控制中心,山东枣庄277000

出　　处：《标记免疫分析与临床》2025年第2期290-296,共7页Labeled Immunoassays and Clinical Medicine

基　　金：山东省医务职工科技计划项目(编号:SDYWZGKCJH2022098);枣庄市科技发展计划项目(编号:2023NS32)。

摘　　要：目的分析2023年12月枣庄市某学校发生的甲型H3N2流感病毒聚集性疫情的流行病学特点和全基因组特征,为流感防控提供参考依据。方法对流感样病例开展流行病学调查,并采集其咽拭子标本进行核酸检测,对阳性标本进行病毒分离。随后对分离得到的毒株进行全基因组测序,利用生物信息学软件分析基因进化特征。结果此次聚集性疫情共报告19例病例,其中16例(84.21%)核酸检测呈甲型H3N2流感病毒阳性,成功分离7株病毒毒株。7株分离株与疫苗株A/Darwin/6/2021同属3C.2a1b.2a2进化分支。与疫苗株A/Darwin/6/2021相比,7株分离株的8个基因节段核苷酸同源性为97.37%~99.50%,氨基酸同源性为94.90%~100.00%。7株分离株血凝素HA蛋白共发生17个氨基酸位点突变,其中4个突变位点位于抗原决定簇,神经氨酸酶NA蛋白发生3个氨基酸位点突变,但这些突变不涉及NA酶活性及其抑制剂耐药位点。此外,多个蛋白糖基化和磷酸化位点发生改变。结论引起本次学校聚集性疫情的病原体是甲型H3N2流感病毒,应加强学校疫情监测并严格执行防控措施。Objective This study aims to analyze the epidemiological characteristics and complete genomic features of an Influenza A H3N2 virus cluster outbreak that occurred in a school in Zaozhuang City,Shandong Province,in December 2023,so as to provide valuable insights for Influenza prevention and control strategies.Methods We investigated the epidemiology of Influenza-like cases and collected pharyngeal swab specimens for nucleic acid testing.Virus from positive samples were isolated,followed by whole genome sequencing of the isolated viral strains.We then analyzed genetic evolutionary characteristics using bioinformatics software.Results This outbreak reported a total of 19 cases,among which 16(84.21%)were confirmed positive for the Influenza A H3N2 virus through nucleic acid testing,and successful isolation was achieved for 7 viral strains.These isolates belong to the evolutionary branch 3C.2a1b.2a2 of the vaccine strain A/Darwin/6/2021.In comparison with the vaccine strain A/Darwin/6/2021,nucleotide homology across all eight gene segments of these isolates ranged from 97.37%to 99.50%,while amino acid homology varied between 94.90%and 100%.Notably,the hemagglutinin(HA)protein in these isolates exhibited 17 amino acid substitutions,four of which were situated within antigenic sites;Additionally,three amino acid substitutions were identified in the neuraminidase(NA)protein;however,these mutations did not affect NA enzymatic activity or resistance to inhibitors.Furthermore,several glycosylation and phosphorylation sites on proteins underwent alterations.Conclusion The Influenza A H3N2 virus is identified as the pathogen responsible for the recent epidemic outbreak in schools,suggesting an enhanced surveillance of the epidemic and rigorous enforcement of control measures are imperative within educational institutions.

关 键 词：甲型H3N2流感病毒 聚集性疫情 全基因组分析 

分 类 号：R373.13[医药卫生—病原生物学]