两起肠炎沙门菌所致食物中毒的病原学研究及溯源分析

An etiological survey and traceability analysis on two foodborne outbreak caused by Salmonella enteritidis

目的探讨两起同地区连续发生的肠炎沙门菌食物中毒分离株之间的分子流行病学关系。方法参照GB 4789.4—2010《食品安全国家标准食品微生物学检验沙门氏菌检验》方法进行病原分离培养,对检出菌株进行表型鉴定;用VITEK-ⅡCompact全自动微生物分析系统检测菌株抗生素敏感性;采用脉冲场凝胶电泳(PFGE)技术对检出菌株进行分子分型和流行病学特征分析。结果共检出23株肠炎沙门菌,其中从25份患者肛拭样本中检出17株,8份从业人员肛拭样本中检出2株,8份留样食物中检出3株,厨具涂抹样本中检出1株。23株肠炎沙门菌血清抗原式均相同(9∶g,m∶-);生物学性状和药敏试验结果基本一致;PFGE图谱带型完全一致(相似度为100%),且与当地散发病例PFGE图谱带型相似。结论综合流行病学调查、病原学检测和分子分型结果,证实这两起食物中毒是由同一来源的肠炎沙门菌污染所引起。

Objective To investigate the molecular epidemiological relationship of Salmonella enteritidis strains isolated from 2 food poisoning events occurred successively in the same location. Methods Pathogen isolation and culture was conducted according to GB 4789. 4-2010. The phenotype of isolates were identified. VITEK-Ⅱ compact automatic bacteria identification system was used for the antibiotic resistance analysis. Pulsed field gel electrophoresis（ PFGE） was used for the molecular subtyping and epidemiological characteristics analysis. Results 23 strains of Salmonella were isolated,among which 17 strains were isolated from anal swab specimens of 25 patients,2 strains from 8 employees,3 strains from reserved sample of food and 1 strain from kitchenware. Serum antigen type were（ 9∶ g,m∶-）. The result of the biological characteristic and antibiotic resistance analysis were basically the same. PFGE pattern were the same. Conclusion Epidemiological investigation,pathogen detection and molecular typing indicated that these two cases of foodborne outbreaks were caused by the same source of Salmonella enteritidis contamination.