一起旅游团聚集性腹泻疫情回顾性队列流行病学调查

Retrospective cohort epidemiological investigation of the clustering of diarrhea among tour group members

目的分析一起旅游团聚集性腹泻疫情的致病因素,提出旅游团聚集性疫情的防控措施。方法应用回顾性队列流行病学研究方法,开展个案访谈,采集有关生物标本和样品开展实验室检测,对相关危害因素进行调查。结果本起疫情的罹患率43.4%(23/53),临床症状以腹泻(95.6%)、腹痛(60.9%)、呕吐(56.5%)为主。发病时间集中在8月20日0~1时之间,平均潜伏期为6.5 h。采集12份样品和4份生物标本,其中1份便标本中检出副溶血弧菌。回顾性队列研究提示某美食城19日晚餐提供的套餐是可疑危险食物[相对危险度(relative risk,RR)=2.844,95%可信区间(confidence interval,CI):1.232~6.562]。结论该起旅游团聚集性腹泻符合细菌性食源性疾病特点。可疑食物是8月19日晚餐时在某美食城食用的套餐,致病因素可能与食物交叉污染、室温下放置较长时间导致细菌增殖有关。

Objective To analyze the pathogenic factors of an epidemic of cluster diarrhea in a tourist group,and put forward the prevention and control measures of tourism agglomeration.Methods Retrospective cohort epidemiological study was used to carry out case interview,relevant biological samples were collected,laboratory tests was carried out,and the relevant risk factors were investigated.Results The attack rate of this event was 43.4%(23/53),and the main clinical symptoms were diarrhea(95.6%),abdominal pain(60.9%) and vomiting(56.5%).The onset time was 0:00-1:00 on August 20,and the average incubation period was 6.5 h.Among 12 samples and 4 biological specimens,Vibrio parahaemolyticus was detected in 1 stool sample.A retrospective cohort investigation suggested that the set menu provided by a food city might be dangerous food [relative risk(RR)=2.844,95% confidence interval(CI):1.232-6.562].Conclusion The clustering of diarrhea of the tour group accords with the characteristics of bacterial foodborne diseases.Suspicious food is a set meal for dinner in a food city on August 20 th,and pathogenic factors may be related to cross-contamination of food and bacterial proliferation caused by long-term storage at room temperature.