1992-2012年中国H3N2亚型流感病毒选择压力分析

Selection pressure analysis of H3N2 influenza virus from China between 1992 and 2012

目的 分析1992-2012年中国H3N2亚型流感病毒所受选择压力,并探讨选择压力与各个抗原类毒株流行情况的关系.方法 对1992-2012年中国的H3N2亚型流感病毒（n=1206）进行抗原类流行和整体选择压力分析,同时对这21年来所有毒株的HA1进行位点正选择压力分析.结果 表明所有H3N2亚型流感病毒在这21年间共有4个位点受到正选择作用,整体选择压力的变化随着不同抗原类毒株的交替而变化,21年间共发现3个选择压力谷底年,与新抗原类的出现相关.结论 整体选择压力从谷底年上升时,新的抗原类出现并在人群中流行,此时是更换疫苗株的最佳时机.

Objective In order to investigate the relationship between selection pressure and the prevalence of antigenic clusters,we sequenced and analyzed the H3N2 influenza virus from China between 1992 and 2012.Methods The H3N2 influenza virus （n =1206） in China from 1992 to 2012 was analyzed,include global selection pressure and sites positive selection pressure analysis.Results Considering all the H3N2 influenza viruses during these 21 years,a total of four amino acid sites subject to positive selection.The global selection pressure varies with the variation of different antigenic clusters and three years with peak bottom selection pressure were identified.Conclusion The global selection pressure rise from the peak bottom,a new antigenic clusters will appear and prevalent in the population,indicating the best time to replace the vaccine strain.