宁波地区甲型副伤寒沙门菌基因分型

目的 了解宁波地区甲型副伤寒沙门菌的脉冲场凝胶电泳（PFGE）基因型和流行优势型，为探讨传播途径和追踪传染源等提供依据。方法 用全自动细菌鉴定仪（Vitek32）确定细菌的生物学特征；用诊断血清确定细菌的血清型；用PFGE方法对细菌的染色体进行基因分型。结果 102株甲型副伤寒沙门苗可分成9个PFGE型，其中X2型73株，占71．57％。X1型21株，占20，58％，X7型2株，占1．96％，其他6个型各1株，分别占0．98％。其中优势型为X2型，菌株的带型变化在1～3条范围内，表明宁波地区的甲型副伤寒沙门菌变异不大，有可能是同一克隆系的甲型副伤寒沙门菌。结论 PFGE分型对探讨伤寒、副伤寒疫情内在联系具有重要意义，该法特异性高、重复性好、结果容易判读，有实际应用价值。

Analysis on gene typing of Salmonella paratyphi A in Ningbo city

Objective To investigate the dominant gene type of Salmonella paratyphi A in Ningbo bypulsed-field gel electrophoresis(PFGE),and to provide a way to distinguish the causing pathogens in the epidomiologic investigations.Methods The biological characteristics and sero-types were determined by Vitek32 and serological test,respectively.Chromosomal gene patterns were typed by PFGE.Results 102 strains salmonella paratyphi A were divided into 9 PFGE types:73 strians in X2 type(accounting for 71.57%),21 in X1 type(20.58%),2 in X7 type(1.96%),while 1 in the each other type(0.9%,respectively).The dominant type was X2.The PFGE DNA fingerprints differed among 1 to 3 bands,which demonstrated that little mutation existed in Salmonella paratyphi A strains in Ningbo,suggesting that all stratus maybe belong to the same clone of Salmonella paratyphi A.Conclusion PFGE typing plays a vital role in surveillance for and the investigation of the outbreaks of Salmonella paratyphi A for its good speciality and reproducibility and easiness to judge.