一起嗜水气单胞菌引起的食源性疾病暴发事件调查

Investigation on an outbreak of foodborne disease caused by Aeromonas hydrophila

目的 调查一起食源性疾病暴发事件的原因,为制定预防控制措施提供依据。方法 采用现场流行病学调查方法,结合病例临床表现、问卷调查及病例对照研究等查找可疑食物。采集病例肛拭子、可疑食物、水样和环境等样本进行实验室检测。结果 共搜索到病例65例,罹患率为24.34%;主要症状以腹痛(100.00%)、恶心(90.77%)、呕吐(16.92%)为主,最短潜伏期为6.8 h,最长潜伏期为46.0 h,平均潜伏期为10.3 h;男女罹患率差异无统计学意义(P>0.05);年龄最小7岁、最大12岁,发病年龄中位数为9岁;病例对照研究及logistic回归分析显示进食米线炒猪肉、炒白菜、炒黄瓜均导致发病风险增加;实验室检测结果显示,7份样本中分离鉴定出嗜水气单胞菌菌株。结论 该起事件为嗜水气单胞菌污染学校食堂用水及食材引起的食源性疾病暴发事件。为避免类似事件再次发生,学校应加强校内用水卫生管理,加强对水源的保护,引水要考虑到卫生消毒及保护设施,工程设计要符合卫生学要求。

Objective To investigate the cause of a foodborne disease outbreak and provide evidence for developing prevention and control measures.Methods Field epidemiological investigation,combined with clinical manifestation,questionnaire survey and case-control study was used to identify suspicious food.Anal swabs,suspicious food,water samples and environmental samples were collected for laboratory testing.Results A total of 65 cases were found,with an attack rate of 24.34%;the main symptoms were abdominal pain(100.00%),nausea(90.77%)and vomiting(16.92%).The shortest incubation was 6.8 h,and the longest incubation was 46.0 h,with the average of 10.3 h;there was no significant difference of attack rates between males and females(P>0.05);the minimum age of the cases was 7 years and the maximum age of the cases was 12 years.The median age of onset was 9 years;the case-control study and logistic regression analysis showed that eating fried pork with rice noodles,fried cabbage and fried cucumber all led to an increased risk of disease;laboratory test results showed that Aeromonas hydrophila strains were isolated and identified in 7 samples.Conclusions This event is an outbreak of foodborne disease caused by Aeromonas hydrophila in the contamination of water and food materials in the school canteen.In order to avoid the recurrence of similar incidents,the school should strengthen the management of water sanitation in the school,strengthen the protection of water sources,consider the sanitary disinfection and protection facilities for water diversion,and the engineering design should meet the requirements of hygiene.