一起胃肠道感染疫情暴发的调查

目的]调查分析2009年某区一起幼托机构的胃肠道感染疫情的病因。方法]通过现场调查和实验室荧光定量PCR方法进行病因确认。结果]此次疫情波及该园中(三)班,共有17人发病,罹患率54.84%,主要临床症状为呕吐、腹痛,少数伴有恶心和发热,无腹泻。该园12个班级中餐及课间餐统一提供同样食品,而发病的幼儿仅局限于1个班级,据此可初步排除幼儿园食物本身问题。发病班级幼儿发病高峰较集中,可推断为同源暴露,初步可排除幼儿在家中感染可能。调查中发现发病前一日该班一保育员有感染腹泻并在发病后继续带病工作,通过荧光定量PCR方法确认该保育员和部分患儿大便和血清标本诺如病毒核酸阳性。结论这是一起聚集性诺如病毒胃肠炎事件,传染源为该班保育员。

INVESTIGATION OF AN EPIDEMIC ABOUT GASTROINTESTINAL INFECTION

Objective]To explore the disease cause of an epidemic about gastrointestinal infection.Methods]Field epidemiological investigation and laboratory fluorescent quantitative PCR were applied to explore and confirm the causes of epidemic disease.Results]In the epidemic,totally 17 children in middle 3rd class of one kindergarten in Jiangdong district were infected,most with vomit and bellyache,a few with nausea and fever,none with diarrhea,the attack rate was 54.84%.Same lunch meal and break refection were provided to 12 classes in the kindergarten,while only the middle 3rd class was affected in the epidemic.So the food provided from the kindergarten could be excluded from the infection cause.The children infected were taken bad during a few hours,which could infer they were infected by a same exposure instead of exposure at home.Therefore it could infer that the infection was caused by factors closely related with the middle 3rd class,such as food distribution.In the following survey,a nursery governess of the middle 3rd class was found having diarrhea the day before the epidemic and holding on working as usual.Later through fluorescent quantitative PCR,same norovirus was found from the serum and stool samples of nursery governess and part of children infected.Conclusion]The epidemic is a group infection caused by norovirus,the source of which is the nursery governess of this glass.