2019年广东省新生儿埃可病毒11型感染事件病原检测结果分析

Analysis of pathogen detection results of neonatal Echovirus 11 infection outbreaks in Guangdong Province in 2019

目的:分析2019年广东省两起医疗机构新生儿肠道病毒感染暴发事件实验室检测结果及埃可病毒11型(Echovirus 11, Echo11)基因特性,为新生儿肠道病毒感染防控提供依据。方法:收集疑似肠道病毒感染新生儿病例病原学标本,采用荧光定量PCR和基因测序两种方法进行肠道病毒分型鉴定,对阳性标本开展病毒分离,对Echo11的VP1基因进行全长序列测定并运用Danstar6、Bioedit7.09和MEGA6.06等生物信息学软件开展遗传进化分析。结果:收集到36例新生儿病例的93份标本,经鉴定,24例55份标本肠道病毒阳性,其中23例为Echo11阳性,1例为柯萨奇病毒B组4型(CVB4)阳性。从19例病例标本中分离到肠道病毒29株,其中18例28株为Echo11,1例1株为CVB4。VP1全长序列分析发现,本研究18株Echo11核苷酸同源性为98.2%~100.0%,两起新生儿感染事件Echo11的核苷酸同源性分别为99.7%~100.0%和99.8%~100.0%,均高度同源;Echo11可分为A、B、C、D、E和F共6个基因型,其中A基因型包含5个亚型(A1~A5),C基因型包含4个亚型(C1~C4),D基因型可分为等5个亚型(D1~D5),本研究18株Echo11均为D5亚型。结论:2019年广东省两起医疗机构新生儿感染暴发事件均由肠道病毒Echo11引起,均属于D5基因亚型。

Objective To analyze the laboratory test results of two outbreaks of neonatal enterovirus infections in Guangdong Province in 2019 and the genetic characteristics of Echo11,aiming to provide reference for the prevention and control of neonatal enterovirus infections.Methods The pathogenic specimens of neonatal cases suspected of enterovirus infection were collected.Fluorescence quantitative PCR and sequencing were used for enterovirus typing and identification,and virus isolation was carried out for positive specimens.The complete sequences of VP1 of Echo11 were amplified and sequenced and the phylogenetic analysis was performed using the bioinformatics software such as Danstar6,Bioedit7.09 and MEGA6.06.Results A total of 93 specimens from 36 neonatal cases were collected.After identification,55 specimens from 24 cases were positive for enterovirus,of which 23 cases were positive for Echo11 and one case was positive for Coxsackievirus B4(CVB4).A total of 29 enterovirus strains were isolated from the specimens of 19 cases,of which 28 were Echo11 from 18 cases,and one was CVB4.Phylogenetic analysis revealed that the nucleotide homology between the 18 strains of Echo11 in this study was 98.2%-100.0%,and the nucleotide homology between the Echo11 strains causing the two neonatal infections was 99.7%-100.0%and 99.8%-100.0%,respectively.Echo11 could be divided into six genotypes as A,B,C,D,E and F,in which genotype A and genotype C were further divided into A1-5 and C1-4,and genotype D could be divided into D1-5.The 18 strains of Echo11 in this study were all subtype D5.Conclusions In 2019,two outbreaks of neonatal infections in medical institutions in Guangdong Province were caused by Echo11,which belonged to the genotype D5.