青海省西宁市某幼儿园一起诺如病毒暴发疫情调查及分子流行特征分析  

Investigation and molecular epidemiological characteristics of a Norovirus outbreak in a kindergarten in Xining City,Qinghai Province

作　　者：赵金华[1] 龙江 李得恩 赵建海[1] 曹海兰[1] 赵生仓 刘桂香[1] 窦艳丽 ZHAO Jin-hua;LONG Jiang;LI De-en;ZHAO Jian-hai;CAO Hai-lan;ZHAO Sheng-cang;LIU Gui-xiang;DOU Yan-li(Institute of Infectious Disease Prevention and Control,Qinghai Provincial Center for Disease Control and Prevention,Xining 810007,China)

机构地区：[1]青海省疾病预防控制中心传染病预防控制所,西宁810007

出　　处：《医学动物防制》2023年第2期116-119,共4页Journal of Medical Pest Control

基　　金：国家“十三五”科技重大专项传染病监测技术平台项目(2017ZX10103006-002);青海省高端创新人才计划项目(2017-2);青海省“昆仑英才高原名医”项目(青人才字[2020]18号);青海省传染性疾病分子生物学重点实验室(依托单位:青海省疾病预防控制中心,受理编号:2021-0402-ZJC-0021)。

摘　　要：目的 调查分析一起由诺如病毒引起的某幼儿园胃肠炎暴发疫情感染来源及分子流行病学特征。方法 采用描述性流行病学方法分析疫情的流行病学特征及感染来源。采集病例的粪便、呕吐物和周围环境的擦拭物,提取核酸病毒RNA后,进行实时荧光核酸检测诺如病毒GⅡ型,GⅡ型阳性产物采用特异性引物分别扩增病毒ORF2区直接测序,采用BLAST和Mega 3.0软件进行序列比对和系统进化分析其分子生物学特征。结果 累计搜索21例诺如病毒病例,罹患率为2.53%(21/831),病例主要集中在3-4岁儿童共19例,占总病例的90.48%,男女性别比为0.62∶1;疫情持续时间为5 d,首发病例发病时间距离疫情报告时间为2.5 d;采集22份标本,其中8例病例,病例标本14份,病例标本阳性检出率为57.14%(8/14),环境标本8份,环境标本阳性检出率为12.50%(1/8);病例标本粪便阳性检出率为87.50%(7/8);经过实时荧光RT-PCR检测有9份标本为诺如病毒GⅡ型阳性,分子分型显示均由GⅡ.17引起。结论 该疫情由诺如病毒GⅡ.17引起的人与人传播;粪便标本阳性检出率较高;低年龄组为主要防控人群。Objective To investigate and analyze the source of infection and molecular epidemiological characteristics of an outbreak of gastroenteritis caused by Norovirus in a kindergarten.Methods Descriptive epidemiological methods were used to analyze the epidemiological characteristics and the sources of infection.Feces, vomit, and the surrounding environment were collected.After nucleic acid viral RNA extraction, real-time fluorescent nucleic acid was used to detect the type GⅡ of Norovirus.The positive products of type GⅡ were individually amplified using specific primers for the viral ORF2 region for direct sequencing.Sequence alignment and phylogenetic analysis of their molecular characteristics using BLAST and Mega 3.0 software.Results A total of 21 Norovirus cases were found, with a incidence rate of 2.53%(21/831).The cases were mainly concentrated in small classes, and 19 cases were found in children aged 3-4 years, accounting for 90.48% of the total cases, with a male to female ratio of 0.62∶1.The duration of the outbreak was five days, and the onset time of the first case was 2.5 days after the outbreak report;22 samples were collected, of which 14 were from 8 cases and the positive rate of case samples was 57.14%(8/14) and 12.50%(1/8) from 8 environmental samples.The fecal positive rate was 87.50%(7/8).A total of 9 samples were positive for Norovirus type GⅡ.17 by real-time fluorescence RT-PCR,and the molecular typing showed that all samples were composed of GⅡ.17.Conclusion The epidemic was transmitted from person to person by Norovirus GⅡ.17.The positive rate of stool samples was high.The low age group is the main population for prevention and control.

关 键 词：青海省 幼儿园 诺如病毒 暴发疫情 分子流行特征 调查 分析 

分 类 号：R373.25[医药卫生—病原生物学]