目的 分析一起学校甲型肝炎暴发疫情的特点和流行原因,为控制疫情提供依据。方法 采用现场流行病学调查方法,结合临床表现及实验室检测结果确定疫情性质,对学校生活饮用水卫生状况进行分析,探讨暴发疫情的原因。 结果 某中学共发生甲型肝炎病例49例,罹患率1.12%,均为高三学生;寄宿生46例,通读生3例。发病高峰期为2月17~19日,占发病总数的32.65%;患者主要临床表现以发热、纳差、巩膜(皮肤)黄染、尿黄、恶心呕吐为主,无重症和死亡病例;在寝室内、教室寝室外饮用直饮水是甲型肝炎患病的危险因素。采集4 494份血样标本检测,49份甲肝IgM阳性,124份标本肝功能异常,32份水样标本检测结果,办公楼一楼管道末梢水、学生宿舍旁地下总污水口污水甲肝病毒核酸阳性,学校自备水井水菌落总数、总大肠菌群、耐热大肠菌群均超标。 结论 该事件为一起甲型肝炎暴发疫情,事件发生主要原因可能是学校饮用水被病原体污染所致。

Objective To analyze the characteristics and causes of an outbreak of hepatitis A in a middle school and provide scientific basis for epidemic prevention and control. Methods The epidemic situation of the drinking water in the school was analyzed with the method of field epidemiological investigation, combined with the clinical and laboratory test results, and the reasons for the outbreak were analyzed. Results A total of 49 cases of hepatitis A were found in a middle school, with attack rate 1.12% and all the patients were grade three high school students. There were 46 resident students and 3 non-resident students. The peak period was 17-19 February, accounting for 32.65% of the total number of diseases. The main clinical manifestations were fever, Nr, sclera (skin) yellow staining, urine yellow, nausea and vomiting. There were no severe or fatal cases. Drinking direct drinking outside the dormitories and classrooms was a risk factor for hepatitis A. We collected 4,494 blood samples, of which 49 of hepatitis A IgM positive, and 124 of abnormal liver function. We tested 32 water samples and results indicated that water from 1st floor piping end of the office building and sewage drain outlet were positive in hepatitis viral nucleic acid. The well water was out of limits in total bacterial count, total coliform group, and heat-resisting coliform. Conclusion The incident was a hepatitis A outbreak.The main reason was the drinking water contaminated by pathogens at the school.