四川省什邡市健康儿童中埃柯病毒11型基因特征分析

Genetic characteristics of echovirus 11 among healthy children in Shifang city, Sichuan province

目的分析四川省什邡市埃柯病毒E11型(echovirus 11,E11)的基因特征。方法对采集的健康儿童大便标本进行肠道病毒(enterovirus,EV)核酸检测、病毒分离和VP1区核苷酸全序列测序,根据进化树聚集确定E11基因型/基因亚型。结果69份标本中,EV核酸阳性32份,选取Ct值≤33的20份标本进行病毒分离,收获毒株14株,其中8株为E11。E11间VP1区核苷酸序列一致性≥99.4%,推导氨基酸序列一致性≥98.9%。进化树分析显示,什邡市E11与D5基因亚型参考株聚集在同一进化分支上。结论什邡市健康儿童中分离到的E11为D5基因亚型,与以前我国流行的基因型(A和C)不同。D5基因亚型E11可引起脑炎、脑膜炎和手足口病等疾病,需对其流行程度和持续时间开展监测。

Objective To analyze the genetic characteristics of echovirus 11 (E11) in Shifang city, Sichuan province. Methods Stool specimens were collected from the healthy children in one urban kindergarten of Shifang city. Enterovirus (EV) nucleic acid detection, virus isolation and sequencing of full length VP1 gene were carried out. Phylogenetic tree was constructed and genogroup/subgenogroup was identified according to phylogenetic clustering. Results Of the 69 stool specimens detected, 32 were EV nucleic acid positive. Twenty stool specimens (Ct≤33) were selected for virus isolation, and 14 strains were harvested, including eight E11 strains. The identities of VP1 gene sequences and deduced amino acid sequences among E11 strains were ≥99.4% and ≥98.9%, respectively. Phylogenetic analysis showed all Shifang E11 were clustered with reference strains of subgenogroup D5. Conclusions The E11 strains isolated from healthy children in Shifang city belonged to subgenogroup D5 and was different from previously reported circulating genogroups (A and C) in China. The E11 strains of subgenogroup D5 may cause encephalitis, meningitis, hand, foot, and mouth disease and other diseases. The surveillance is needed concerning the extent and duration of its circulation.