2022—2023年襄阳市流感监测甲型H3N2流感病毒基因特征分析  

Genetic characteristics of influenza A H3N2 virus influenzaseason in Xiangyang City in 2022-2023

作　　者：史静 童芳莉 朱胜明 甘云霞 马露 佟娜仁其木格 方斌[2] 陈鹏 杨刚 SHI Jing;TONG Fangli;ZHU Shengming;GAN Yunxia;MA Lu;TONG Narenqimuge;FANG Bin;CHEN Peng;YANG Gang(Xiangyang Center for Disease Control and Prevention,Xiangyang,Hubei 430074,China;Hubei Provincial Center for Disease Control and Prevention,Wuhan,Hubei 430079,China)

机构地区：[1]湖北省襄阳市疾病预防控制中心,湖北襄阳430074 [2]湖北省疾病预防控制中心,湖北武汉430079

出　　处：《公共卫生与预防医学》2024年第3期32-36,共5页Journal of Public Health and Preventive Medicine

摘　　要：目的了解2022—2023年襄阳市流感监测分离的H3N2亚型流感病毒流行情况、HA及NA基因遗传进化规律与氨基酸的变异,为预测流感病毒流行和变异提供科学依据。方法每周收集国家流感监测哨点医院流感样病例标本,用实时荧光定量方法检测流感病毒核酸,对H3N2阳性标本进行病毒分离,进行HA和NA基因扩增和测序,构建分子进化树和建模分析,分析基因特征和变异情况。结果系统发育进化树显示2022和2023年分离的H3N2分离株分别属于3C.2a1b.2a1和3C.2a1b.2a2分支。2022—2023年襄阳市A(H3N2)流感毒株均在重要抗原决定簇上发生点突变。2022年毒株的抗原表位突变主要发生在B、C和D区。2023年毒株的抗原表位突变主要发生在C区和D区。2022—2023年毒株HA基因发生不同的糖基化位点改变,未发现与神经氨酸酶抑制剂耐药相关的关键氨基酸位点发生变异。三维模拟结构图中总体结构差异不明显。结论此研究中的A(H3N2)流感病毒毒株出现了抗原漂移,尤其是HA的变异可能影响疫苗对该地区人群保护作用,导致流感流行。HA和NA多个氨基酸位点的变异提示应密切关注H3N2亚型流感病毒的流行与基因变异情况,为流感病毒疫苗株推荐及防控提供科学依据。Objective To analyze the prevalence and genetic characteristics of influenza A(H3N2)viruses in the city of Xiangyang in 2022-2023,and to provide a scientific basis for predicting the epidemic and mutation of influenza virus.Methods Throat swab specimens of the influenza like cases were collected from national influenza monitoring sentinel hospitals in Xiangyang every week.RNA was extracted from the specimens for influenza diagnosing using real-time RT-PCR.Viruses were isolated from H3N2 positive specimens,and HA and NA genes were amplified and sequenced.3D modeling analyses were conducted.Results The gene phylogenetic tree showed that the H3N2 isolates in 2022-2023 belonged to 3C.2a1b.2a1 and 3C.2a1b.2a2 branches,respectively.The A(H3N2)influenza virus strains all had amino acid point mutation sites on important antigenic determinants of HA protein.The epitope mutations of the 2022 A(H3N2)strain mainly occurred in regions B,C,and D.The epitope mutations of the A(H3N2)strain in 2023 mainly occurred in regions C and D.Different glycosylation sites of HA gene were found in 2022-2023 strains.No variation was found in key amino acid sites associated with neuraminidase inhibitor resistance.The difference of overall structure was not obvious in the three-dimensional simulation structure diagram.Conclusion The A(H3N2)influenza strains isolated in this study have shown antigenic drift,especially the mutation of HA,which may affect the protective effect of the vaccine on the local population and lead to influenza epidemic.The variations of HA and NA suggest that close attention should be paid to the epidemic and genetic variation of H3N2 subtype influenza virus,to provide a scientific basis for the selection of influenza virus vaccine strains and the prevention and control of influenza.

关 键 词：H3N2亚型流感病毒 HA基因 NA基因 基因特征 

分 类 号：R183[医药卫生—流行病学]