2015-2016年阜阳市柯萨奇病毒A16型分离株VP1区基因特征分析

Analysis of VP1 gene characteristics of coxsackievirus A16 isolates in Fuyang during 2015-2016

目的分析阜阳市柯萨奇病毒A16型(CVA16)分离株VP1区基因特征。方法将2015-2016年阜阳市手足口病患儿CVA16核酸阳性咽拭子标本,接种RD细胞分离病毒,出现细胞病变后用荧光定量PCR鉴定,鉴定阳性标本用RT-PCR扩增VP1区基因片段并进行核苷酸序列测定。采用Mega 6.06生物软件与国内外CVA16毒株参考序列构建进化树,分析VP1区基因特征。结果 26份CVA16核酸阳性的咽拭子合格标本分离出10株CVA16毒株,阳性率为38.46%;10株病毒VP1区基因亲缘性关系分析表明:2株CVA16毒株为B1a亚型,8株为B1b亚型;B1a亚型毒株和广州2012年的CVA16分离株同源性最高,核苷酸同源性为98.0%,B1b亚型毒株和深圳2013、2014年的分离株同源性最高,核苷酸同源性为99.0%。结论 2015-2016年阜阳市分离的CVA16流行毒株株为B1a亚型、B1b亚型,以B1b亚型为主。

Objective To analyze the gene characteristics of VP1 gene of coxsackievirus A16 （CVA16） isolated from Fuyang city. Methods CVA16 positive swab specimens collected from children with hand-foot-mouth disease in Fuyang, 2015-2016, were inoculated with RD cells to isolate the virus. The cells were identified by fluorescence quantitative PCR; the VP1 gene was amplified from the positive samples by RT-PCR and the DNA sequence of the PCR product was determined. Mega 6.06 software was used to construct the phylogenetic tree with reference sequences of CVA16 strains, and the genetic characteristics of VP1 gene were analyzed. Results 10 CVA16 strains were isolated from 26 positive swab samples, with a positive rate of 38.46%. Phylogenetie analysis of the VP1 gene of 10 CVA16 isolates showed that the 2 CVA16 strains were Bla subtype, and 8 strains were Blb subtype.The Bla subtype strain had the highest homology （98.0%） with the CVA16 strain isolated in Guangzhou in 2012. The homology of Blb subtype strains and the isolates in Shenzhen in 2013 and 2014 was the highest （99.0%）. Conclusion CVA16 strains isolated from Fuyang in 2015-2016 were Bla subtype and Blb subtype, and were mainly Blb subtype.