2016年-2018年无锡惠山区手足口病流行特征及CVA6型肠道病毒VP1基因特征

Epidemic characteristics of hand foot,and mouth disease and genetic characteristics of enterovirus CVA6 type VP1 gene in Huishan District,Wuxi City from 2016 to 2018

目的了解2016年-2018年无锡惠山区手足口病肠道病毒流行特征,并对CVA6型肠道病毒VP1基因进行分子进化特征分析。方法采集疑似手足口病咽、肛拭子标本,采用实时荧光RT-PCR方法检测肠道病毒,对非EV71非CVA16其他肠道病毒扩增VP1基因,测序比对分析,获得肠道病毒谱;对CVA6型肠道病毒构建系统进化树,分析其进化趋势。结果 2016年-2018年惠山区手足口病主要集中在5岁及以下儿童,尤其以3岁~<5岁最多,主要流行株以CVA16型为主,其他肠道病毒的流行共有11种基因型,其中CVA6型为优势流行株。27株CVA6型肠道病毒同源性为93.5%~100%,进化分析显示2017年独成一支,2016年和2018年成为一支,而2018年毒株是在2016年毒株的基础上进一步进化。结论 2016年-2018年无锡惠山区手足口病病原由多种基因型的肠道病毒共同流行,CVA16型为主要的优势流行株。CVA6有逐渐增多的趋势,且相对比较活跃,今后还需长期监测深入研究。

Objective To understand the characteristics of enterovirus prevalence of hand,foot and mouth disease and to analyze the molecular evolution characteristics of CVA6 enterovirus VP1 gene in Huishan District,Wuxi City from 2016 to 2018.Methods Samples of pharyngeal and anal swabs suspected to be hand-foot-mouth disease were collected,and intestinal viruses were detected by real-time fluorescence RT-PCR. The phylogenetic tree of CVA6 enterovirus was constructed and its evolutionary trend was analyzed. Results HFMD was mainly concentrated in children aged 5 years and below,especially 3-< 5 years old in Huishan District,Wuxi City from 2016 to 2018. The main epidemic strain was CVA16 type. There were 11 genotypes of other enterovirus,among which CVA6 type was the dominant epidemic strain. The homology of 27 strains of CVA6 enterovirus was within 93. 5%-100%. Evolutionary analysis showed that the strain became a single strain in 2017,a strain in 2016 and a strain in 2018,and the strain in 2018 were further evolved on the basis of the strain in 2016. Conclusion The etiology of hand,foot and mouth disease was co-prevalent by various genotypes of enterovirus in Huishan District,Wuxi City from 2016 to 2018,and CVA16 was the dominant epidemic strain. CVA6 is gradually increasing and relatively active,which needs long-term monitoring and in-depth study in the future.