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目的:对2016年新疆发生的一起食源性疾病的暴发进行流行病学调查及分子溯源分析。方法:2016年4月3日，新疆某地发生一起食源性疾病暴发事件。依据《食品安全事故流行病学调查指南（2012版）》，共发现142例病例，其中疑似病例138例、确诊病例4例。通过入户调查、面对面访谈的方式进行问卷调查，收集人口学信息、发病和诊疗情况、发病前3 d的饮食史和饮水史、食品的污染源等信息，并采集病例呕吐物及粪便、剩余冰激凌、加工冰激凌剩余牛奶及其他原料、牛奶供应站的牛奶等27份样本，采用脉冲场凝胶电泳（PFGE）和全基因组测序（WGS）进行分子分型、毒力基因以及单核苷酸多态性分析。结果:142例病例年龄n M为9岁，范围为1~66岁；以散居儿童和学生为主，占比为76%（107/142）。男性罹患率［5.5‰（65/11 717）］与女性罹患率［5.8‰（77/13 262）］的差异无统计学意义（n P>0.05）。主要临床表现包括恶心（94%，133/142）、呕吐（92%，131/142）和腹痛（67%，95/142）等。27份样本共计分离获得22株金黄色葡萄球菌，未分离到其他病原菌。PFGE结果显示，产A+C+E混合型毒素的16株菌（包含病例呕吐物及粪便分离株和冰激凌加工点食品分离株）带型相似度为100%。根据WGS分子分型结果显示，9株菌（包括4株患者分离株、4株冰激凌加工点食品分离株、1株牛奶供应站分离株）为ST1（Sequence Type）、1株菌为ST5405。ST1型菌株聚集在一个大簇中，其中7株菌聚集成一个小簇（74 SNPs），其余2株菌聚集成1个小簇（127 SNPs）。n 结论:该起食源性疾病暴发可判定是一起由金黄色葡萄球菌引起的食物中毒暴发事件。“,”Objectives:To analyze the causes of a foodborne outbreak in rural areas of Xinjiang between April 2 and April 5 in 2016.Methods:Cases and the relevant background information were obtained by consulting outpatient records of local health centers and regional people′s hospitals and interviewing doctors and residents. All samples were collected by the laboratory test through epidemiological and food hygiene investigations. The χn 2 test (Fisher′s exact probability method) was used to compare differences in incidence rates. Molecular typing, virulence genes and single nucleotide polymorphisms (SNPS) were analyzed by using Pulsed Field Gel Electrophoresis (PFGE) and Whole Genome Sequencing (WGS).n Results:A total of 142 cases were found in this study, with incidence rate at 5.7‰ (142/24 979). Among all cases, the main symptoms were nausea (94%), vomiting (92%) and abdominal pain (67%), and the incubation period was about 2 h (1-7.5 h). There were 16 n Staphylococcus aureus isolates identified and all of them could produce A+C+E mixed enterotoxin. PFGE showed 100% homology. WGS further revealed that there were 9 and 1 strains contained by Sequence Type 1 (ST1) and ST5405, respectively. All ST1 strains were in the same clade on the genome tree. Among these, 7 strains shared close proximity (74 SNPs) and 2 strains shared close relationships as well (127 SNPs). The n S. aureus isolates that caused the outbreak were introduced by a mutant isolate from the milk supply station.n Conclusions:This foodborne outbreak was mainly caused by n Staphylococcus aureus contamination.n