2012～2016年新疆柯萨奇病毒A6的分子流行病学特征分析

Genetic Characteristics of Coxsakievirus A6 Circulating in Xinjiang,China,from 2012 to 2016

分析新疆手足口病相关的柯萨奇病毒A6(Coxsackievirus A6,CV-A6)毒株VP1区基因特征。2012～2016年从新疆手足口病病例标本中分离到75株CV-A6,对75株CV-A6采用RT-PCR方法扩增VP1区基因片段并进行核苷酸序列测定,应用MEGA5.05和BioEdit7.1.9软件进行核苷酸序列比对分析,构建系统进化树。75株新疆CV-A6毒株VP1区核苷酸序列同源性为86.9%～100%,与原型株(Gdula)同源性为81.4%～82.5%;71株D3亚型株与D3代表株之间核苷酸序列同源性为93.1%～99.6%;4株D2亚型株与D2代表株之间核苷酸序列同源性为92.6%～96.5%。进化树图分析显示,新疆CV-A6毒株均属于D基因型,其中绝大多数(71/75)处于D3分支,属于D3亚型,2012～2016年具有分布;少数(4/75)处于D2分支,属于D2亚型,只分离于2013～2014年。新疆CV-A6在系统进化树上形成多个不同的小分支,不同年份不同地区的CV-A6毒株分别与国内一些地区的毒株有着较近的亲缘关系,说明新疆CV-A6毒株的传播链和基因型分布与内地CV-A6相同,与内地的CV-A6共进化的。加强手足口病的病原学监测及相关病原的分子特征研究对手足口病的防控至关重要。

To analyze the genetic characteristics of the VP1 region of coxsackievirus A6(CV-A6)strains associated with hand,foot and mouth disease(HFMD)circulating in Xinjiang,China.75 strains of CV-A6 were isolated from the samples of HFMD patient in xinjiang from 2012 to 2016 The nucleotide sequences of the VP1 region were amplified by reverse transcription polymerase chain reaction(RT-PCR)and sequenced.The homological analyses and phylogenetic tree of VP1 gene of CV-A6 were conducted using MEGA v5.05 and BioEdit v7.1.9 software.The 75 strains of CV-A6 shared nucleotide homology of86.9%～100% with each other,and 81.4%～82.5% with the prototype strain(Gdula).The 71 strains in the D3 branch shared 93.1%～99.6% nucleotide homology with representative D3 strains.The 4 strains in the D2 branch shared 92.6%～ 96.5% nucleotide homology with representative D2 strains.According to the phylogenetic tree,All 75 strains of CV-A6 in Xinjiang belonged to D genotype,the majority of them(71/75)were in the D3 branch,belonged to the D3 subgenotype,with distribution in every year from 2012 to 2016.A few(4/75)in the D2 branch,to the D2 subgenotype.only separated in 2013 and 2014.The phylogenetic tree shows that xinjiang CV-A6 strains formed several different small branches,and the strains in different prefectures or in different years were closely related to that in some regions in China,which suggesting that the transmission chain and genotype distribution of xinjiang CV-A6 was the same as that of the inland one and they evolved together.It is necessary to strengthen the pathogenic surveilliance,and related molecular characteristics analyses must be carried out.