目的调查和分析一起发生在江苏省常州市某小学急性胃肠炎爆发疫情,明确流行病学特征和基因型特征。方法根据统一设计的流行病学调查表,对病例和对照的饮食、饮水和卫生习惯等情况开展病例对照研究。对病例的排毒情况进行跟踪调查,明确排毒期长短。采集病例和对照的标本,进行荧光定量PCR方法检测,对部分阳性结果标本进行测序以明确基因型。结果 11月22日起出现首例病例,11月22日至12月2日为主要发病阶段。此期共发病269例,其中学生发病264例,罹患率17.4%,教师发病5例,罹患率4.4%,两者存在统计学差异(χ2=13,P<0.01);排毒期调查结果显示,本起暴发疫情最短排毒期为发病后3d,最长为14d,中位时间为7d。共采集172份标本,其中82份检测结果为诺如病毒GII型阳性,未检测到轮状病毒及腺病毒,18份诺如病毒GII型阳性标本测序分析显示均为GII.12基因型。结论结合病例临床特征、流行病学调查及实验室检测结果综合分析,判定本起疫情为诺如病毒GII.12型感染导致的急性胃肠炎爆发疫情,该型别在我省尚为首次发现。爆发原因可能为呕吐物-口引起的大范围传播。 Objective To investigate and analyze the outbreak of acute gastroenteritis in a primary school in Changzhou, Jiangsu Province, and to make clear the epidemiological and genotypic characteristics. Methods According to the unified design epidemiological questionnaire, case-control study was conducted on case and control diet, drinking water and hygiene habits. Detoxification of the case to follow-up investigation, a clear detoxification period. Samples of cases and controls were collected and tested by real-time quantitative PCR. Sequences of positive samples were sequenced to confirm genotypes. Results The first case occurred on November 22, November 22 to December 2 as the main stage of disease. There were 269 cases in this period, of which 264 cases were students, the attack rate was 17.4%, the incidence of teachers was 5% and the attack rate was 4.4% (χ2 = 13, P <0.01) The minimum outbreak of the outbreak since the onset of detoxification 3d, the longest 14d, the median time of 7d. A total of 172 samples were collected, of which 82 were positive for Norovirus GII, no rotavirus and adenovirus were detected, and 18 Norovirus GII-positive samples were sequenced and showed GII.12 genotype. Conclusions Based on the clinical characteristics, epidemiological investigation and laboratory test results, the outbreak of acute gastroenteritis caused by Norovirus GII.12 infection was identified as the first case of this type in our province . The cause of the outbreak may be a wide spread of vomit-induced mouth.