2016年北京某幼儿园一起柯萨奇病毒A6引起的聚集性手足口病分子流行病学分析

目的了解2016年北京市某幼儿园一起手足口病聚集性疫情CA6的分子流行病学特征,分析其变异情况。方法用实时荧光PCR对该聚集性疫情标本进行初步病原学鉴定。提取核酸,对其VP1区全长序列进行RT-nPCR扩增和测序。从Genbank中选取不同年代不同地域的CA6参考序列,利用生物信息学软件进行同源性和系统进化分析。结果共扩增到3条CA6 VP1序列(Genbank登录号为KY231153-KY231155),3株CA6与Genbank参考序列在VP1区的核苷酸序列同源性为83%~98%。进化分析表明,该3株CA6与2012年以来我国流行的CA6在同一进化树分支上。结论引起此次聚集性疫情的CA6毒株与2012年以来我国流行的CA6毒株亲缘关系密切,未发生明显变异。

Epidemiological analysis of coxsackie virus A6 isolated from a cluster epidemic of hand foot and mouth disease in a kindergarten in Beijing (2016)

Objective To genetically characterize the variation of VP1 region of CA6 isolated from a cluster epidemic of hand foot and mouth disease in a kindergarten in Beijing in 2016.Methods CA6 positive samples of the cluster cases were identified by realtime PCR.Virus RNA was extracted and the complete VP1 region was amplified by RT-nPCR.CA6 sequences of different periods and regions were selected from Genbank as reference sequences.Sequence and phylogenetic analyses were performed.Results Three strains of CA6 were identified (Genbank accession No.KY231153-KY231155),which shared 83％-98％ nucleotide similarity with reference sequences during the VP1 region.Phylogenetic analysis showed that,the 3 strains of CA6 were clustered with the CA6 epidemic strains of China since 2012.Conclusion The CA6 isolates of the cluster were genetically closely related to prevalent CA6 strains in China since 2012,and no significant variation was detected.