北京市2010年-2011年儿童甲型H3N2流感病毒神经氨酸酶基因进化和耐药性位点分析

目的:了解2010年9月1日-2011年8月31日期间北京市儿童甲型H3N2病毒的神经氨酸酶基因进化和耐药性位点情况。方法:采集儿童流感样病例标本,分离与鉴定流感病毒。选取14株甲型H3N2流感毒株进行神经氨酸酶(NA)基因的扩增和序列测定。并对NA的基因变异、进化特点和耐药性位点进行分析。结果:共分离64株甲型H3N2毒株。序列分析发现2010年-2011年毒株NA抗原决定簇氨基酸位点发生变异。进化树分析结果显示NA基因进化为不同的两支。毒株NA耐药性位点无变异。结论:北京市2010年-2011年儿童甲型H3N2流感毒株NA基因呈现两个不同的进化分支,基因特性有明显改变,尚未有耐药位点变异。

Molecular characterization of neuraminidase genes and neuraminidase drug resistance of influenza H3N2 virus circulating in Beijing children during 2010-2011

Objective:To understand the molecular characterization of neuraminidase(NA) genes and NA drug resistance of influenza H3N2 virus in Beijing children during the period from Sep.2010 to Aug.2011.Methods:A total of 1040 pharyngeal swab specimens from surveillance systems were collected and cultured by MDCK cell.NA genes of the selected virus strains were amplified and sequenced.Furthermore,sequence alignment and phylogenic analysis were performed using bioinformatics software.Results:During 2010-2011 influenza season,a total of sixty four H3N2 virus strains were isolated.NA genes of influenza H3N2 viruses showed obvious amino acid changes in antigenic epitopes and evolved two divergent genetic clusters.No NA drug resistance mutations were observed.Conclusion:The NA genes of influenza H3N2 viruses in this study showed two divergently genetic evolution pathways and NA drug resistance mutants were not found.