2017—2020年新疆流感网络实验室检测数据分析

Analysis of detection data of influenza network laboratory in Xinjiang from 2017 to 2020

目的了解新疆流行性感冒(流感)病毒检出的时间分布,初步分析2017—2020年季H3亚型流感HA基因的演变过程以及与疫苗株匹配情况,为科学防控流感提供依据。方法分析流感监测系统中2017—2020年全疆流感网络实验室的流感核酸检测结果;对每个流行年度2株季H3亚型毒株的HA基因进行测序,与每年的疫苗株一起绘制种系发生树。结果2017—2020年全疆流感网络实验室检测样本50515份,流感病毒检出阳性率为14.64%,季节性流感4种亚型均有检出,其中阳性率甲型11.12%、乙型3.52%,甲型流感H3N2亚型检出最多(38.25%),其次是新甲H1(37.71%);阳性率2018年最高(21.85%)、2020年最低(3.99%),2017—2020年总体检出阳性数较多的3个月依次为12月(2473份,33.44%)、1月(1995份,26.97%)和11月(1224份,16.55%)。2017年和2018年的4个HA序列结果在一个小分支,2019年和2020年6个序列在一个小分支,10株均与疫苗株A/Singapore/INFIMH-16-0019/2016在同一分支,疫苗株A/Hong Kong/4801/2014和A/Kansas/14/2017在单独的分支。结论2017—2020年新疆流感检出集中在11月至次年1月,甲型流感检出率高于乙型流感,2019—2020年新疆H3N2亚型流行株与2019年推荐的疫苗株不在同一分支上;流感网络实验室连续开展流感监测,有助于及早发现流感病毒的变异特征。

Objective To understand the time distribution of influenza virus detection in Xinjiang,and preliminarily analyze the evolution process of HA gene of H3 subtype influenza and its matching with vaccine strains from 2017 to 2020,so as to provide basis for scientific prevention and control of influenza.Methods The influenza nucleic acid detection results of the influenza network laboratory in Xinjiang in the influenza monitoring system from 2017 to 2020 were analyzed.The HA genes of two seasonal H3 subtype strains in each epidemic year were sequenced,and the phylogenetic tree was drawn together with the annual vaccine strains.Results From 2017 to 2020,50515 samples were detected at influenza network laboratory in Xinjiang,with positive rate of influenza virus of 14.64%.Four subtypes of seasonal influenza were detected,with the detection rate of 11.12%of type A and 3.52%of type B.The most detected subtype was H3N2 subtype(38.25%),followed by new H1 subtype(37.71%).The detection rate was the highest of 21.85%in 2018 and the lowest of 3.99%in 2020.From 2017 to 2020,the three months with higher positive results were in December(2473,33.44%),January(1995,26.97%)and November(1224,16.55%).There were 4 HA sequences in a small branch in 2017 and 2018,while 6 sequences in 2019 and 2020 were in a small branch,and 10 strains were in the same branch of vaccine strain A/Singapore/INFIMH-16-0019/2016,vaccine strains A/Hong Kong/4801/2014 and A/Kansas/14/2017 were in a separate branch.Conclusions The detection for influenza in Xinjiang concentrates in the period of November to January of the next year from 2017 to 2020,with higher detection rate of type A than that of type B.The H3N2 subtype epidemic strain in Xinjiang is not in the same branch as the vaccine strain recommended in 2019.Continuous influenza surveillance at influenza network laboratory is helpful to detect the variation characteristics of influenza virus as early as possible.