目的利用脉冲场凝胶电泳技术,对一起伤寒爆发疫情的病原进行分子分型,为今后采取有效防控措施提供参考。方法采用查阅临床诊疗记录、病例搜索、个案调查、病例对照调查、环境卫生学调查和病原及其分子分型等检测后进行分析。结果2007年8月2日～9月15日共报告伤寒病例57例,主要集中在8月下旬及9月上旬,均为在押男性犯人,分布于第14监区,罹患率为22.30%。犯人近2～3年没有明确伤寒菌苗接种史。本起疫情主要危险因素是与病人日常接触,餐饮具等可能是重要传播媒介。病原学调查为伤寒沙门菌,脉冲场凝胶电泳分型有4种带型,其中有2种主要带型,为同一克隆系(相似系数94.43%),均为多重耐药菌。结论日常接触传播所致,疫情报告延迟及疾病识别能力差,应加强监狱等封闭场所传染病预防与控制。 OBJECTIVE: To identify the pathogen of an outbreak of typhoid fever by using pulsed-field gel electrophoresis and to provide a reference for effective prevention and control measures in the future. Methods The clinical records, case searches, case studies, case-control surveys, environmental hygiene surveys and pathogen and molecular typing were used for analysis. Results A total of 57 cases of typhoid fever were reported from August 2 to September 15, 2007, mainly in late August and early September. All of them were male prisoners in custody located in the 14th surveillance area with an attack rate of 22.30%. Nearly 2 to 3 years inmates do not have a clear history of vaccination against typhoid fever. The main risk factors for the outbreak were daily contact with patients, and tableware and the like may be important media. The etiologic investigation was Salmonella typhi, and there were 4 types of genotypes in pulsed-field gel electrophoresis. Among them, there were 2 main bands with the same clonal type (similarity coefficient 94.43%), all of which were multi-resistant bacteria. CONCLUSIONS: Due to the spread of routine contacts, the reporting of epidemics is delayed and the ability of disease identification is poor, and the prevention and control of infectious diseases in closed places such as prisons should be strengthened.