2017-2018年广东省深圳市疱疹性咽峡炎患者肠道病毒分子流行病学研究

Molecular epidemiology of enteroviruses among herpangina patients in Shenzhen,Guangdong,2017−2018

目的了解广东省深圳市疱疹性咽峡炎(HA)病原组成与病原体的分子特征,为HA的预防与控制提供科学依据。方法2017—2018年收集了157例HA患者的314份临床样本,其中粪便样本和咽拭子各157份。使用荧光定量逆转录-聚合酶链反应(RT-PCR)和基于半巢式RT-PCR扩增的测序方法对肠道病毒(EV)进行检测与分型。使用生物信息学软件对病毒VP1基因进行序列分析。结果在126例(80.30%,126/157)EV阳性的患者中,共检出10种EV,检出率最高的是柯萨奇病毒A组10型(CVA10)(19.70%,31/157),其次是CVA4(17.80%,28/157)、CVA6(15.30%,24/157)和CVA2(10.80%,17/157),其他病原体包括CVA5(4.50%,7/157)、CVA16(3.20%,5/157)、EV-A71(1.30%,2/157)、CVA8(0.60%,1/157)、CVB5(0.60%,1/157)和埃可病毒11(E11)(0.60%,1/157),1例为CVA4与CVA10的混合感染(0.60%,1/157)。2017年检出率最高的两种病原体是CVA2和CVA6,而2018年却是CVA10和CVA4。粪便样本与咽拭子的病原检出率之间的差异没有统计学意义(χ^(2)=0.019,P=0.892)。基于VP1序列的分子系统发育分析表明,本研究CVA10毒株均为C2基因型。CVA4除了1株为C5基因型外,其余均为C2基因型。1株CVA6毒株位于先前未描述的进化分支,其他CVA6毒株均为D3a基因亚型。CVA2毒株均为D2基因型。结论粪便样本与咽拭子都适用于HA的病原体核酸检测。CVA10、CVA4、CVA6和CVA2是2017—2018年深圳市HA的优势病原体,大部分毒株是我国主流基因型,个别毒株处于不常见的基因型或进化分支。

Objective The(sero)type distribution and molecular characteristics of enteroviruses(EV)associated with herpangina(HA)in Shenzhen were investigated to provide scientific basis for HA control and prevention.Methods A total of 314 clinical specimens from 157 HA patients,including 157 feces specimens and 157 throat swabs,were collected between 2017 and 2018.EV types were determined using real-time reverse transcription polymerase chain reaction(RT-PCR),RT nested PCR,and sequencing.VP1 sequences were analyzed using bioinformatics programs.Results Ten EV types were detected in 126 EV-positive HA patients(80.30%,126/157).The most predominant pathogen was coxsackievirus A10(CVA10)(19.70%,31/157),followed by CVA4(17.80%,28/157),CVA6(15.30%,24/157)and CVA2(10.80%,17/157).Other pathogens detected included CVA5(4.50%,7/157),CVA16(3.20%,5/157),EV-A71(1.30%,2/157),CVA8(0.60%,1/157),CVB5(0.60%,1/157)and echovirus 11(E11)(0.60%,1/157).One patient co-infected CVA4 with CVA10.The predominant pathogens were CVA2 and CVA6 in 2017,but CVA10 and CVA4 became predominant in 2018.There was no statistically significant difference(χ^(2)=0.019,P=0.892)between the pathogen detection rates of feces specimens and throat swabs.Molecular phylogeny based on the complete VP1 gene indicated that all CVA10 strains from this study were assigned to genotype C2.All CVA4 strains except for one strain which was assigned to genotype C5 belonged to genotype C2.All CVA6 strains except for one strain which grouped in a previously uncharacterized clade were assigned to sub-genotype D3a.All CVA2 strains belonged to genotype D2.Conclusion Both feces specimens and throat swabs are suitable for EV RNA testing for HA.The main pathogens were CVA10,CVA4,CVA6 and CVA2 in HA patients from 2017 to 2018 in Shenzhen,China.A majority of strains belonged to the genotypes which were prevalent in China.And individual strain grouped in an uncommon genotype or clade.