一起副溶血性弧菌食物中毒的现场流行病学调查分析

Investigation on a food poisoning outbreak caused by Vibrio parahaemolyticus

目的查明一起食物中毒事件的发生原因和可疑危险因素来源。方法通过流行病学曲线及回顾性队列研究查找可疑餐次,对可疑餐次食物开展病例对照研究,分析食用不同食物与食物中毒的关联性,并采集可疑食物和病例等标本进行实验室检测。结果共发现87例病例,症状主要为腹泻（96.5%）、腹痛（91.9%）、呕吐（44.8%）、发热（32.2%）。20日午餐（RR=21,95%CI=9.2~47）、晚餐（RR=4.9,95%CI=3.3~7.3）均是本次疑似食物中毒的暴露餐次。烧鸭（OR=26,95%CI=5.7~118）和白切鸡（OR=21;95%CI=2.5~180）是发病的危险因素。厨师在对白切鸡及烧鸭切块过程中发生交叉污染可能是此次食物中毒的感染环节。病例肛拭子检测为副溶血性弧菌阳性。结论食用被副溶血性弧菌污染的白切鸡和烧鸭是导致本次食物中毒的主要原因,建议加强对餐饮机构厨师的监督管理,提高其卫生安全意识,防止类似事件再次发生。

Objective To investigate the cause of a food poisoning outbreak,and the origins of the suspicious factors of this case.Methods The suspicious meal was chased according to the epidemiological curve and retrospective cohort study.Then evaluate the foods in the suspicious meal through case-control study,and analyze the correlations between different foods and different dozes. Foods and case samples were collected for laboratory testing. Results 87 cases were founded and the major symptoms were diarrhea（96.5%）,abdominal pains（91.9%）,vomiting（44.8%） and so on. Lunch（RR =21,95% CI =9.2-47）and dinner（RR =4.9,95% CI =3.3-7.3）of August 20 were the suspected food poisoning exposure meal times. Eating poached chicken（OR=21,95% CI=2.5-180）and roast duck（OR=26,95% CI=5.7-118）were the risk factors. The main reason for cross contamination was that the chef processed the poached chicken and roast duck at the same time.Vibrio parahaemolyticus was detected in the anus swab samples from patients. Conclusion The food poisoning were caused by poached chicken and roast duck contaminated by Vibrio parahemolyticus.It is necessary to strengthen the supervision and administration of catering distribution,and improve health consciousness of the public to prevent food poisoning.