2000—2005年广州地区稻叶型霍乱弧菌的分子分型

Molecular subtyping of Vibrio cholerae serotype Ogawa isolated in Guangzhou area from 2000 to 2005

目的分析2000—2005年广州地区霍乱暴发点、散发事件和环境监测分离的稻叶型霍乱弧菌的致病相关基因型和脉冲场凝胶电泳技术(PFGE)分型,探讨该稻叶型霍乱的流行特征和趋势。方法对分离株进行噬菌体生物分型,采用多重PCR方法检测菌株的4种致病相关基因,应用PFGE进行分子分型,并采用软件BioNumerics Version 4.0进行聚类分析。结果广州地区稻叶型霍乱菌株中存在3种致病相关基因型:A、B和C型。98%感染者分离株为致病相关基因A型,45%环境分离株为C型。82株菌分为39个不同的PFGE型。各年份稻叶型暴发与散发事件中均存在具有PFGE分型特征一致的菌株,而环境中菌株则存在多种不同的PFGE型,来源不同地区分离株也均有相似的分型特征。结论噬菌体-生物分型、致病相关基因分型和PFGE分型存在一定的关联规律性,分子分型可为分析霍乱疫情和预警提供技术平台。

Objective To study epidemic characteristics and trends of Vibrio cholerae（V, cholerae） serotype Ogawa in Guangzhou area and analyze the pathogenicity-related genes types and pulse field gel electrophoresis（PFGE） types of V. cholerae serotype Ogawa strains isolated from 2000 to 2005. Methods Phage-biotyping and multiplex polymerase chain reaction assay were applied in detecting the four pathogenicity-related genes of Ogawa V. cholerae. PFGE was employed for the molecular subtyping and PFGE results were then analyzed with BioNumerics Version 4.0 software. Results There were three pathogenicity-related gene types found in isolated V. cholerae Ogawa strains, which were named as type A, B and C. Ninety-eight percent of the isolates from people infected belonged to pathogenicity-related genes type A and forty-five percent of environmental strains belonged to type C. Thirty-nine distinct PFGE types were obtained from all 82 isolated strains. The same PFGE subtyping characteristics existed in both strains isolated from outbreak and those from sporadic events at the same year, while different PFGE subtypes were found in the environmental strains. The local strains and those imported from other provinces and even from foreign countries showed the similar subtyping sometimes. Conclusions There is a correlative relationship among the results of phagebiotyping, multiplex polymerase chain reaction assay and PFGE. Molecular subtyping database of V. cholerae should be established in order to prevent and control outbreak of cholera.