一起中学学生食物中毒的流行病学调查与分析

Epidemiological survey and analysis on food poisoning event among middle school students

目的运用描述性和分析性流行病学研究分析本次食物中毒事件的主要危险因素。方法通过流行病学曲线查找可能暴露时间,采用队列研究推断可疑餐次,采用病例对照研究分析可疑食物,并采集剩余食物和病例标本进行实验室检测。结果共发现66例可疑病例,罹患率为2.57%（66/2 567）,主要症状为恶心（94.4%）、呕吐（74.1%）、腹痛（66.7%）等。4月10日二楼早餐进食者与未进食者的罹患率之比为4.42（3.84%/0.87%）,与发病存在统计学关联（RR的95%CI=2.36~8.29）。食用蛋炒饭的发病风险增加（OR=3.78,95%CI=1.69~8.46）。结论本次事故为一起疑似蜡样芽胞杆菌食物中毒,学校应加强对食堂的卫生监管,防止类似事件再次发生。

Objective To investigate main risk factors of food poisoning event using descriptive and analytic epidemiology. Methods The epidemiological curves were applied to find out the possible exposure time. The cohort study was applied to evaluate the suspicious meal and the case-control study was applied to analyze the suspicious food. Then the suspicious food and case samples were collected for laboratory testing. Results 66 cases were found and the attack rate was 2.57%（66/2 567）. The main symptoms were nausea（94.4%）, vomit（74.1%）, abdominal pain（66.7%） and so on. The attack rate ratio of students who had breakfast in second dining room on April 10 th to students who didn＇t was 4.42（3.84%/0.87%）, and there was statistical association between having breakfast on April 10 th and the prevalence（95%CI of RR=2.36~8.29）. Eating fried rice with egg was the risk factor（OR=3.78, 95%CI=1.69~8.46）. Conclusion This event is one case of food poisoning possibly caused by Bacillus cereus, school should strengthen health supervision to prevent such case.