一起食源性诺如病毒GII．4／Sydney_2012变异株感染暴发的调查  

An epidemiological investigation on a food-born outbreak of noroviru caused by Sydney 2012 GII .4 strain

作　　者：蔡文锋[1] 谢华萍[1] 刘于飞[1] 袁俊[1] 肖新才[1] 丁鹏[1] 陈纯[1] 张笃 陈建东[1] 马晓薇[1] 耿进妹[1] 林东明[3] 练桂雄[3] 杨智聪[1] 

机构地区：[1]广州市疾病预防控制中心,510440 [2]广东省从化市疾病预防控制中心 [3]广州市番禺区疾病预防控制中心

出　　处：《中华流行病学杂志》2013年第8期804-807,共4页Chinese Journal of Epidemiology

基　　金：基金项目：国家科技重大专项（2012ZX10004213-005）;广州市医药卫生科技重点项目（201102A212006）

摘　　要：目的调查广州市某高校急性胃肠炎病例的感染来源、传播途径和危险因素。方法按照病例定义开展病例搜索，采用描述性流行病学和病例对照研究进行分析；样本采用RT-PCR检测诺如病毒核酸，阳性标本分析基因核苷酸序列并进行同源性分析。结果2013年1月8—21日该校共发生诺如病毒感染性腹泻141例，罹患率为8．5％。（141／16600）；8—9日为发病高峰；病例无班级和宿舍聚集性；病例对照调查显示A餐厅为早期病例的感染场所（OR=3．46，95％CI：1．07～11．16），1月7日的午餐是可疑餐次（OR=4．34，95％CI：1．18。17．37），可疑食物是手撕鸡套餐（OR=17．82，95％CI：4．46～78．17）；采集病例和厨工肛拭子、剩余食物及环境涂抹样等266份，诺如病毒RT-PCR检测阳性21份（17例），病例阳性率为42．8％（9／21），A餐厅厨工阳性率为29．6％（8／27），经基因测序为GⅡ．4／Sydney变异株，学生、教职工病例与厨工同源性为_2012100％。结论该次疫情为诺如病毒GII．4／Sydney变异株感染引起的急性胃肠炎暴发，其原．2012因是携带病毒厨工污染食物所致，以食源性传播途径为主。Objective To identify the source of infection, route of transmission and risk factors related to a cluster of acute gastroenteritis cases in a university of Guangzhou. Methods Cases were identified according to the definition. Descriptive epidemiological approaches and case- control study designs were employed in the analysis. All the samples were tested for norovirus by RT-PCR. Positive samples were subjected to both nucleotide sequence and homology analysis. Results A total of 141 cases related to norovirus gastroenteritis were identified in January 8 to 21, 2013, with the attack rate as 8.5%0 （ 141/16 600）. The peak in morbidity was seen on January 8 to 9. No clustering was found in different classes or dormitories. Results from the case-control study revealed that early cases were infected in Restaurant A （0R=3.46,95%CI： 1.07-11.16） and the cold shredded chicken set meal （OR= 17.82, 95%CI： 4.46-78.17） served at lunch （0R=4.34, 95%CI： 1.18 -17.37） on January 7 was under suspicion. A total of 266 samples, including rectal swabs from the patients and kitchen wokers, leftover food and environmental swabs, were collected. Twenty-one samples （collected from 17 persons） were positive for norovirus by RT-PCR. About 29.6% （8/27） of the kitchen workers in the Restaurant A were tested positive for the virus. The pathogen was identified as the new norovirus genotype II .4 variant, termed Sydney 2012. The virus strains isolated from the patients among student and staff and the kitchen workers were 100% identical in their nucleotide sequence. Conclusion This was the first reported acute gastroenteritis outbreak caused by the new norovirus genotype II .4 variant, Sydney 2012, which showed that the food was contaminated by the asymptomatic kitchen workers who carried the virus.

关 键 词：诺如病毒 急性胃肠炎 暴发 流行病学 

分 类 号：R511[医药卫生—内科学]