2017年吉林省水痘-带状疱疹病毒分子特征分析

摘要

目的 分析2017年吉林省水痘-带状疱疹病毒(varicella zoster virus,VZV)基因型别,区分疫苗株与野毒株.方法 2017年1～3月在吉林省收集到的10份疑似水痘患者的疱疹液或咽拭子样本,采用实时荧光定量PCR方法检测病毒核酸,用普通PCR扩增病毒的ORF22、ORF38和ORF62的特定区域.用ORF22的5个SNPs确定病毒株的基因型别,用ORF38和ORF62的4个SNPs区分疫苗株与野毒株.使用MEGA5和BioEdit软件分析序列结果.结果 10份疑似样本均为VZV阳性,Clade 2遗传支.其中JL17-7样本在38 048位发生了C→T的同义突变.ORF22核苷酸的亲缘性关系树分析发现,10份样本均和Clade 2代表株在同一个分支上,与Clade 2代表株的核苷酸与氨基酸同源性分别为99.5％～100％和99.3％～100％.10份样本的ORF38和ORF62的4个特异SNPs均为A-T-T-T,与野毒株一致.结论 2017年吉林省流行的VZV均属Clade 2遗传支,且均为野毒株.%Objective To clarify the genotype of varicella-zoster virus (VZV) in Jilin province in 2017,and to discriminate between vaccine strain and wild-type strain.Methods Vesicle fluid and throat swab samples were collected from 10 individuals with suspected VZV in Jilin province from January to March of 2017.Real-time fluorescent quantitative PCR was used to detect viral nucleic acid.Specific regions of ORF22,ORF38 and ORF62 of VZV were amplified by PCR.Viral genotype was determined by five SNPs of ORF 22 and vaccine strain or wild-type strain was distinguished by four SNPs of ORF 38 and ORF 62.The results were analyzed with MEGA5 and BioEdit software,using the VZV reference strain sequences from GenBank.Results VZV-positive strains were detected in 10 samples,all belonged to Clade 2.There was a synonymous mutation (C→T) in position 38 048 of JL17-7 strain.The nucleotide homology of ORF22 showed that all 10 samples were on the same branch with the Clade 2 referenced strains.Compared with Clade 2 referenced strains,the homology of nucleotide and amino acid for all 10 samples were 99.5％-100％ and 99.3％-100％,respectively.The four specific SNPs of ORF38 and ORF62 in 10 samples were A-T-T-T,which were consistent with wild-type strain.Conclusions This study reveals that the VZV strains circulating in Jilin province in 2017 were all wild-type strains belonging to Clade 2.