中国四省甲型副伤寒分离株脉冲场凝胶电泳分析及分型数据库建立

目的对中国4个甲型副伤寒流行省份的分离株进行标准化脉冲场凝胶电泳（PFGE）分型分析。方法对来自4个省的甲型副伤寒沙门菌利用XbaⅠ酶切染色体DNA进行PFGE分析，利用BioNumerics建立数据库和进行相似性聚类。结果分离自1998-2002年的89株甲型副伤寒分离株共有11种PFGE带型，这些菌株中具有优势带型。有3种带型相似性在96．3％，这3种带型的菌株占到分析菌株的865％，并在不同省份和年度中出现。结论建立了中国甲型副伤寒沙门菌的用于网络监测分析的PFGE技术和数据库，近年中国部分省份的甲型副伤寒沙门菌分离株PFGE型别集中，存在同型菌株的广泛流行。

Molecular typing of Salmonella paratyphi A isolates from four provinces with pulse-field gel electrophoresis

Objective To analyze the molecular types of Salmonella paratyphi A strains isolated in the recent years, and to construct the standard S. paratyphi A databank in the laboratory surveillance network PulseNet China. Methods S. paratyphi A isolates from 4 provinces were analyzed with the standard pulsed-field gel electrophoresis (PFGE) protocol used in PulseNet and their patterns compared. The databank was constructed with BioNumerics. Results Eleven PFGE patterns were obtained, in which 3 predominant patterns were identifies with a similarity coefficient of 96.3 % . The strains of these patterns, accounted for 86.5% of the analyzed strains, appeared in different provinces and years. Conclusion The databank of S. paratyphi A was constructed and could be used in laboratory surveillance of S . paratyphi A in PulseNet China. From the analyses on molecular typing of the isolates, data suggested that the predominant strains might cause the epidemics in different regions.