无锡市腹泻病人沙门菌的病原学特征及分子分型研究

目的分析无锡市腹泻人群中分离的沙门菌的流行特征;同时比较主要血清型菌株间的脉冲场凝胶电泳(PFGE)带型差异,为沙门菌感染的防控提供实验数据。方法收集2015年无锡市腹泻病人的粪便标本,分别进行沙门菌的分离鉴定、药敏试验、血清型分型以及PFGE分型分析。结果 756份粪便标本中共分离到32株沙门菌,阳性率为4.23%;检出时间主要集中在5~10月份,感染人群以老年人为主。药敏试验说明无锡地区的沙门菌对氨苄西林的耐药率最高,达56.25%;对环丙沙星和头孢他啶的耐药率最低,均为6.25%。32株沙门菌共鉴定出11种血清型,以肠炎沙门菌和鼠伤寒沙门菌为主,分别占31.25%和21.88%。对这2种血清型的沙门菌进行PFGE分析,显示肠炎沙门菌所有带型的相似度均在85%以上,鼠伤寒沙门菌的带型各不相同。结论无锡市沙门菌的感染具有明显季节和年龄分布差异性,流行的优势血清型为肠炎沙门菌。无锡市需同时加强对食品和环境中沙门菌的监测。

Pathogenic characteristics and molecular typing of Salmonella strains isolated from diarrhea patients in Wuxi City,Jiangsu Province,China

We analyzed the pathogenic characteristics of Salmonella strains isolated from diarrhea patients in Wuxi City,Jiangsu Province,China and compared the differences among pulse field gel electrophoresis (PFGE) patterns of main serotype strains,so as to provid scientific basis for disease control.After biochemical identification of the Salmonella strains isolated from infectious diarrhea patients in Wuxi in 2015,drug susceptibility test,serotyping and PFGE were applied to analyze these strains.Results showed that a total of 32 Salmonella strains were detected from 756 diarrhea specimens with a positive rate of 4.23 ％.The infection occurred more frequently between May and October and adults aged more than 60 years old affected mostly.There was no significant difference between genders in infected population.The drug susceptibility test indicated that the antibiotic resistance rate of these Salmonella strains to ampicillin (56.25 ％) was the highest,and to ciprofloxacin(6.25 ％)and Ceftazidime (6.25％) were the lowest.The 32 Salmonella strains belonged to 11 serotypes,and S.enteritidis(31.25％)and S.typhimurium(21.88％) were the predominant serotypes.PFGE showed that the pattern similarity of all S.enteritidis was more than 85 ％;PFGE patterns of S.typhimurium were different.In conclusion,the infection of Salmonella from diarrhea patients in Wuxi City had obvious season and age specific distribution,and the most prevalent serotype of Salmonella was the S.enteritidis.It is necessary to strengthen the surveillance of Salmonella concurrently in food and environment.