上海市多家医院供水系统中分离的嗜肺军团菌血清1型基因多态性分析

目的 对上海市多家医院供水系统中分离的嗜肺军团菌血清1型(LP1)基因进行分型,探讨各家医院之间LP1基因型的相关性及其差别.方法 2009年5-9月份共采集上海市8家医院供水系统水样,分离LP1,应用脉冲场凝胶电泳技术进行LP1基因分型,对分型结果进行聚类分析,探讨菌株间的相互关系.结果 上海市8家医院共采集193份水样,每份水量500 ml,5家医院的水样中共分离到24株LP1.24株LP1共分为A～E 6型,其中流行株为A(8株)、B(6株)及E(7株)3型.不同医院可存在相同的基因型,5家医院中3家存在不同的基因型.结论 环境中的军团菌基因型较为稳定,主要的流行株为A、B和E型.由于一家医院内可存在多种基因型,故流行病学调查时需应用分子生物学技术确定感染源.

Abstract：

Objective To classify Legionella pneumophila serogroup 1( LP1 ) isolated from the water distribution systems in hospitals of Shanghai by using genotying methods, and therefore to explore the genetic relationship between different genotypes. Methods LP1 was isolated from 8 hospitals in Shanghai, and strains of LP1 were subtyped using pulse field gel electrophoresis ( PFGE ). Genotyping results of PFGE were classified as dendrogram, and cluster analysis was used to compare the genetic characteristics of different strains. Results Twenty-four strains of LP1 were isolated from 193 water specimens. LP1 belonged to 6PFGE genotypes, of which 21 belonged to 3 predominant genotypes. Different hospitals shared the same genotype, while some strains isolated from the same hospital had different genotypes. Conclusion The genetic characteristics are stable in environmental LP1. Molecular biology techniques should be added to epidemiological study for hospital acquired legionellosis due to the genetic diversity in one hospital.

Genetic diversity of Legionella pneumophila serogroup 1 in hospital water distribution systems in Shanghai

Objective To classify Legionella pneumophila serogroup 1( LP1 ) isolated from the water distribution systems in hospitals of Shanghai by using genotying methods, and therefore to explore the genetic relationship between different genotypes. Methods LP1 was isolated from 8 hospitals in Shanghai, and strains of LP1 were subtyped using pulse field gel electrophoresis ( PFGE ). Genotyping results of PFGE were classified as dendrogram, and cluster analysis was used to compare the genetic characteristics of different strains. Results Twenty-four strains of LP1 were isolated from 193 water specimens. LP1 belonged to 6PFGE genotypes, of which 21 belonged to 3 predominant genotypes. Different hospitals shared the same genotype, while some strains isolated from the same hospital had different genotypes. Conclusion The genetic characteristics are stable in environmental LP1. Molecular biology techniques should be added to epidemiological study for hospital acquired legionellosis due to the genetic diversity in one hospital.