2020年西藏自治区0~5岁健康儿童携带埃可病毒11型的基因特征分析

Genetic characteristics of echovirus 11 among healthy children in Tibet Autonomous Region in 2020

目的本研究旨在通过对2020年西藏自治区5岁以下健康儿童中携带埃可病毒11型(echovirus11,E11)的基因特征进行研究,掌握肠道病毒的流行情况,填补西藏自治区关于E11基因特征研究的空白。方法收集2020年在中国西藏自治区内采集的0~5岁健康儿童的粪便标本,通过病毒分离和肠道病毒分子定型方法,对阳性病毒分离物进行肠道病毒血清型鉴定,并对鉴定结果为E11的病毒分离物进行全长VP1区扩增及核苷酸序列测定和分析。使用MEGA软件构建基因进化树(最大似然法),与中国其他省份E11和全球E11进行遗传进化分析。结果574份粪便标本中分离到89株肠道病毒分离株,其中E11有44株,是主要的血清型,VP1区核苷酸序列之间的相似性为96.4%~100%,在系统发育树上呈现为多个传播链,但均属于D5基因亚型,且与我国2017年后其它省份E11流行株聚为一簇。结论本研究获得了我国西藏自治区流行的E11的基因特征的基本信息,并了解了全球E11的基因型分布。

Objective To study the genetic characteristics of echovirus 11(E11)carried by healthy children under 5 years of age in the Tibet Autonomous Region in 2020,so as to understand the prevalence of enterviruses and fill gap in the study of genetic characters of E11 in Tibet Autonomous Region.Methods The fecal samples of healthy children aged 0 to 5 years were collected in the Tibet Autonomous Region of China in 2020.Through viral isolation and molecular typing method for enterovirus,the positive virus isolates were identified for enterovirus serotype,and the virus isolates identified as E11 was amplified for entire VP1 region,and the nucleotide sequence was determined and analyzed.MEGA software was used to construct the genetic evolution tree with the maximum likelihood method,and the phylogenetic analysis with the E11 strains in other provinces of China and in the world was carried out.Results From 574 fecal samples,89 enterovirus strains were isolated,including 44 strains of E11 which was the dominant serotype.The similarities of nucleotide sequence in VP1 region were 96.4%-100%.Multiple transmission chains were observed in the phylogenetic tree,but all strains were D5 subgenotype,and clustered with E11 epidemic strains in other province of China after 2017.Conclusions This study obtained the basic information about the genetic characteristics of prevalent E11 in Tibet Autonomous Region of China,and understood the global genotype distribution of E11.