一起食源性伤寒暴发疫情的耐药分析和分子分型

Drug resistance analysis and molecular types of an outbreak of foodborne typhoid fever

目的研究一起食源性伤寒暴发疫情的伤寒沙门菌的耐药情况和分子分型特点,为伤寒防制工作提供依据。方法病例及外环境标本采用分离培养、生化鉴定与血清学分型进行菌株鉴定,并对菌株进行10种抗生素的敏感性试验,同时运用脉冲场凝胶电泳(Pulsed field gel electrophoresis,PEFG)技术对菌株进行分子分型和流行病学特征分析。结果共培养分离出93株伤寒沙门菌,分别为92份病例和1份外环境井水标本。选取14株本次暴发疫情、7株往年菌株、1株邻市和1株外环境井水标本进行PFGE检测,结果显示井水与江阴市13株和邻市1株沙门菌带型一致,从分子流行病学角度可基本确认是由一种型别的病原菌引起的伤寒局部流行。来自病例标本的73株伤寒沙门菌对阿莫西林、头孢噻吩、头孢噻肟敏感率100.00%,对萘啶酸、利福平耐药率100.00%。结论加强PFGE和耐药监测的运用,可以及时掌握伤寒菌株型别、耐药变迁情况,准确治愈伤寒病例,采取针对性防控措施,防止伤寒疫情扩散和蔓延。

Objective To study the drug resistance and molecular typing characteristics of Salmonella typhimurium in a food-borne typhoid outbreak,and provide evidence for the prevention and treatment of typhoid fever.Methods Case and external environmental specimens were identified by isolation culture,biochemical identification and serotype.Antibiotic susceptibility was tested on 10 strains.Pulsed field gel electrophoresis(PEFG)was used to analyze the molecular and epidemiological characteristics of the strain.Results A total of 93 strains of Salmonella typhimurium were isolated from this outbreak.It’s 92 cases and 1 external well water.14 strains of this outbreak,7 strains of this city in previous years,1 adjacent city and 1 external well water were selected for PFGE detection.The results showed that the well water was consistent with 13 plants in this city and 1 plant in the adjacent city.From the point of view of molecular epidemiology,it can be confirmed that this outbreak is caused by a type of pathogenic bacteria.The sensitive rate to amoxicillin,cephalothiophene,cefotaxime of 73 swains of typhoid fever was 100.00%.And all strains were resistant to naphthidine acid and rifampicin.Conclusion Strengthening the application of PFGE and drug resistance monitoring can timely grasp the type of typhoid strain and drug resistance,accurately cure typhoid cases,and take targeted prevention and control measures to prevent the spread and spread of typhoid fever.