贵州省20例水痘患者水痘-带状疱疹病毒基因型分析

目的 了解贵州省20例水痘患者流行的水痘-带状疱疹病毒(VZV)主要基因型别,为水痘疫情的防控提供科学依据。 方法 收集20份临床诊断水痘患者血清标本、咽拭子或水疱液标本,分别用ELISA法检测VZV IgM抗体、实时荧光定量PCR检测VZV特异性核酸、普通PCR扩增VZV开放阅读框(ORF)22核酸片段,用BioEdit和MEGA 4软件分析测序结果,并与Genbank上VZV参考株序列比较,进行生物信息学分析。 结果 20份临床诊断病例VZV IgM抗体检测均为阳性,其中7份咽拭子或水疱液标本实时荧光定量PCR检测为阳性,3例标本的PCR产物在约447bp处有明显目的条带,测序证实为水痘-带状疱疹病毒。ORF22基因的单核苷酸多态性(SNP)分析显示,GZVZV001和GZVZV007核酸片段完全一致,GZVZV002序列在37922位点出现R碱基取代G碱基。3株分离株序列与J基因型参考株p-OKa序列比较,一致性为99%~100%,与E基因型参考株DUMAS序列比较,在6个关键位点上有4个碱基不一致,与M1基因型参考株CA123比较,6个关键位点上有3个碱基不一致。提示3株分离株为VZV J基因型。 结论 贵州省目前VZV流行的野毒株型别中存在J基因型,加强VZV疫苗的接种能有效防止水痘的爆发流行。

Genotype analysis of varicella-zoster virus among 20 varicella cases in Guizhou province

Objective To learn the genotype of varicella-zoster virus in Guizhou province in order to provide a scientific basis for the development of prevention and control measures for varicella epidemic. Methods The serum,throat swabs,or blister fluid specimens of 20 patient clinical diagnoses with varicella were collected. Tested varicella zoster virus (VZV) IgM by ELISA,and tested VZV nucleic acid by Real-time PCR,and did the amplification of the open reading frame (ORF) 22 of VZV and sequencing. And then analyzed the sequence with BioEdit and MEGA 4 software,and comparing the sequence with the data of VZV reference strains downloaded from Genbank,and did bioinformatics analysis. Results All the 20 patients were VZV IgM positive,and 7 throat swaps or blister fluid specimens were Real-time PCR positive,and the 447bp fragments in the ORF 22 were amplified with 3 throat swaps or blister fluid specimens by PCR. The sequencing results were confirmed the VZV. The results of ORF22 single nucletotide polymorphism (SNP) analyses showed that GZVZV001 and GZVZV007 had the same sequence,and R substitutes G base in position 37 922 of GZVZV002. The identity with J genotype reference strain p-OKa was percent 99 to 100. Compared with E genotype reference strain DUMAS,the 3 strains had 4 bases different on 6 key sites,and 3 bases different with M1 genotype reference strain CA123. So the 3 strains were identified as VZV J genotype. Conclusion The epidemic genotype of VZV has J genotype of wild viruses strain in Guizhou province,and strengthening the immunization of VZV vaccine is able to prevent the varicella outbreak epidemic.