上海市闵行区鼠伤寒沙门菌病原学与PFGE分型研究

目的了解2015年-2017年闵行区腹泻病监测点鼠伤寒沙门菌的病原学及脉冲场凝胶电泳(PFGE)特征。方法按照《上海市腹泻病综合监测实施方案》进行沙门菌分离鉴定;药物敏感试验采用纸片扩散法(K-B法);PFGE参照Pulse Net China沙门菌PFGE分子分型标准操作规程。结果鼠伤寒沙门菌在2015年-2017年检出率呈逐年增长趋势;鼠伤寒沙门菌对10种抗生素耐药率为四环素56.32%、萘啶酸31.03%、氯霉素20.69%、复方新诺明17.24%、头孢噻肟8.05%、头孢呋辛8.05%、庆大霉素5.75%、环丙沙星3.45%、头孢西丁1.15%、诺氟沙星1.15%,存在多重耐药。PFGE将87株鼠伤寒沙门菌分为62个带型,每个带型含1株~5株菌,分为A、B两大聚类,相似度为57.2%~100%。结论经过多种抗生素共同作用筛选得到的菌株成为鼠伤寒沙门菌扩散的主要来源,在PFGE优势克隆系中能体现。PFGE技术为聚集性病例的追踪溯源提供了分子生物学依据。

Study on phenotypic characteristics and PFGE typing of Salmonella typhimurium in Minhang District,Shanghai

Objective To understand the phenotypic characteristics and PFGE typing of Salmonella typhimurium isolated from acute diarrhea patients collected in the surveillance site in Minhang District from 2015 to 2017.Methods Salmonella typhimurium isolates were identified according to the Shanghai Integrated Management Plan for Diarrhoeal Diseases.The drug sensitivity test was performed by the disk diffusion method(K-B method);the PFGE was referred to the Pulse Net China Salmonella PFGE molecular typing standard operating procedure.Results The detection rate of Salmonella typhimurium in2015-2017 was increasing year by year.The resistance rate of Salmonella typhimurium to 10 antibiotics was tetracycline(56.32%),nalidixic acid(31.03%),chloramphenicol(20.69%),compound sulfamethoxazole(17.24%),cefotaxime(8.05%),cefuroxime(8.05%),gentamicin(5.75%),ciprofloxacin(3.45%),cefoxitin(1.15%),norfloxacin(1.15%).62 PEGE typing were shown in 87 strains of Salmonella typhimurium which were divided into two clusters,A and B,with similarities between 57.2%-100%.Conclusion The strains screened by multiple antibiotics have become the main source of Salmonella typhimurium diffusion,which can be reflected in the PFGE dominant clonal line.PFGE typing of Salmonella typhimurium provides molecular biology evidence for tracking traceability of clustered cases.