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目的:对淮南市发生的一起宋内志贺菌暴发疫情进行病原学溯源分析，并对菌株毒力基因和耐药谱进行检测。方法:采集2020年8月淮南市一起感染性腹泻暴发疫情相关水样、粪便，进行多重病原体核酸检测和分离培养，对分离的宋内志贺菌进行毒力基因PCR检测、微量肉汤法药敏检测、脉冲场电泳和全基因组测序溯源分析。结果:56份黏稀样粪便分离出38株宋内志贺菌（阳性率67.86%），血清型均为宋内志贺菌Ⅰ相；3份末梢水和井水革兰阴性菌（GN）增菌液荧光PCR检测志贺菌阳性；菌株毒力基因携带情况为侵袭性质粒抗原H（n ipaH）阳性（38份），侵袭性质粒抗原H（n ipaH）/侵袭相关基因（n ial）阳性（31份），侵袭性质粒抗原H（n ipaH）/侵袭相关基因（n ial）/肠毒素2基因（n sen）阳性（1份）；耐药谱显示14种抗生素中9种100.00%耐药，仅亚胺培南、氯霉素、头孢他啶、环丙沙星为有效药物；36株菌n XbaⅠ限制性酶切图谱带型完全一致，其中3株菌株基因组ST型分析均为ST152型；全基因组测序和分析验证了此次暴发由单一克隆群菌株引起，且揭示此次暴发分离株与数据库中3株中国菌株、1株韩国菌株聚集成一个大簇，而与其他国家的菌株距离较远。n 结论:本起由水源污染单一宋内志贺菌克隆引起，分离株为低毒力株，呈多重耐药表型。“,”Objective:To understand the virulence gene and drug resistance profile of n Shigella sonnei outbreak in Huainan city, and conduct pathogenic traceability analysis.n Methods:Water samples and feces related to an infectious diarrhea outbreak in Huainan city in August 2020 were collected for multiple pathogen detection. Virulence gene, drug sensitivity, pulse-field gel electrophoresis and whole genome sequencing of n Shigella isolates were analyzed respectively.n Results:38 strains of n Shigella sonnei were detected in 56 samples of mucilage feces with a positive rate 67.86%, and all serotypes were n Shigella sonnei Phase I. Three strains of n Shigella sonnei were detected by fluorescence PCR in the Gram-negative (GN) bacterial enrichment solution of terminal water and well water. Virulence genes were n ipaH positive (38), n ipaH/ial (31) and n ipaH/ial/sen positive (1), respectively. The drug resistance spectrum showed that 9 of 14 antibiotics were 100% resistant, and only imipenem, chloramphenicol, ceftazidime and ciprofloxacin were effective drugs. n XbaⅠ restriction enzyme map type of 36 isolates was completely consistent, and the ST type analysis of 3 strains was ST152. Whole genome sequencing and analysis verified that the outbreak was caused by a single clonal group of strains, and revealed that the isolates of the outbreak were clustered into a large cluster with 3 Chinese strains and 1 Korean strain in the database, far away from the strains of other countries.n Conclusion:The outbreak is caused by a single clone of n Shigella sonnei, which are low virulence strains and have multiple drug resistance.n