重庆地区5岁以内儿童腹泻病毒病原及流行病学特点

目的了解重庆地区5岁以内儿童腹泻病毒病原及流行病学特点。方法收集重庆医科大学附属儿童医院2010年8～11月就诊的5岁以内腹泻患儿的粪便标本共500份,采用胶体金法检测A组轮状病毒(Rotavirus,RV),RT-PCR法检测B、C组RV、诺如病毒(Norovirus,NV)GⅠ和GⅡ、肠道腺病毒(Adenovirus,ADV)、札如病毒(Sapovirus,SLV)和星状病毒(Astrovirus,ASV),取NV和SLV阳性PCR产物测序,并对病毒基因进行分型。采用MEGA 5.05软件构建进化树,Kimura’s two-parameter法计算遗传距离,邻接法(Neighbor-joining)boot-strap重复检验1 000次。结果 500份标本中,检测到A组RV阳性标本134份,阳性率为26.8%;NV GⅡ型阳性标本132份,阳性率为26.4%;ADV阳性标本31份,阳性率为6.2%;SLV阳性标本9份,阳性率为1.8%;ASV阳性标本1份,阳性率为0.2%;未检测到B、C组RV和NV GⅠ型。随机选择22份NV阳性标本进行测序及基因分型,其中GⅡ/4占绝对优势,其次为GⅡ/6、GⅡ/2、GⅡ/3和GⅡ/7。SLV可分为4个基因亚型,其中GⅠ/1为优势株,其次为GⅠ/2、GⅡ/1和GⅠV 1。结论重庆地区5岁以下儿童腹泻以病毒感染为主,RV是主要的病原体,其次为NV、ADV、SLV和ASV。

Etiological and epidemiological characters of diarrhea virus in children at ages of less than 5 years in Chongqing Region, China

Objective To investigate the etiological and epidemiological characters of diarrhea viruses in children at ages of less than 5 years in Chongqing Region,China.Methods A total of 500 fecal samples were collected from children,at ages of less than 5 years,who visited Children's Hospital of Chongqing Medical University from August to November 2010,and tested for rotavirus(RV) group A by colloidal gold method,while for RV groups B and C,norovirus(NV) GⅠ and GⅡ,enteric adenovirus(ADV),sapovirus(SLV) and astrovirus(ASV) by RT-PCR.The PCR products positive for NV and SLV were sequenced,of which the genotypes were then classified using the clustering methods reported previously.The genetic distances were calculated by Kimura's two-parameter method.Phylogenetic trees with bootstrap analysis from 1 000 replicas were constructed using the MEGA program version 5.05 by the neighbor-joining method.Results RV group A was the most frequent virus identified in 134 of 500 samples(26.8%),followed by NV GⅡ(132 / 500,26.4%),ADV(31 / 500,6.2%),SLV(9 / 500,1.8%) ASV(1 / 500,0.2%).However,no RV groups B and C or NV GⅠ were detected.Twenty-two NV-positive samples were selected randomly for sequencing and genotyping,in which GⅡ/ 4 was defined as the predominant strain,followed by GⅡ / 6,GⅡ / 2,GⅡ / 3 and GⅡ / 7.SLV was classified into 4 genotypes,of which GⅠ/ 1 was predominant,followed by GⅠ/ 2,GⅡ/ 1 and GⅠV 1.Conclusion Enteric viruses are a major cause of diarrhea in children at ages of less than 5 years in Chongqing Region,of which RV is the most common etiological agent,follow by NV,ADV,SLV and ASV.