广州市水产品副溶血性弧菌污染状况调查及PFGE分型研究

Investigation of contamination status of Vibrio parahaemolyticus in Guangzhou seafood and molecular subtyping on strains isolated

目的：了解广州市水产品副溶血性弧菌污染状况并应用脉冲场凝胶电泳（PFGE）技术对28株副溶血性弧菌菌株进行分子分型分析。方法：2005-2006年陆续从餐饮单位、肉菜综合市场和超级市场采集虾、蟹、鱼、贝壳和生吃料理等168份检材,采用MPN法定量检测副溶血性弧菌,参照GB/T4789.7-2003分离、鉴定副溶血性弧菌;并采用限制性内切酶NotI,对28株副溶血弧菌进行PFGE分子分型,用BioNumerics Version 4.0软件（复选Dice相关系数和UPGMA方法）分型图谱进行聚类分析。结果：168份水产品共检出副溶血性弧菌57份,检出率为33.93%,其中贝壳类的带菌率最高,为55.56%;虾蟹类、鱼类次之（两者之间的带菌率无显著性差异,P〉0.05）;28株副溶血弧菌分为27个不同的PFGE型,归为7个聚类群（Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ群）,各群间相似系数〈77.4%。结论：广州市水产品副溶血性弧菌污染较严重,卫生部门应采取有效措施防止由水产品引起的副溶血性弧菌食源性疾病;PFGE分型结果与菌株的水产品种类、采样时间、采样地点没有关联,提示当时当地水产品中副溶血性弧菌不存在流行趋势。

Objective ： To learn about the contamination status of Vibrio parahaemolyticus in seafood of Guangzhou area and apply pulsed - field gel electrophoresis （PFGE） in the molecular subtyping of 28 strains of Vibrio parahaemolyticus isolated, nethods：MPN method was utilized to assay quantitatively Vibrio parahaemolyticus and isolated strains was identifed according to National Standards of Microbiological Examination for Vibrio parahaemolyticus（ GB/T4789.7 -2003 ） from 168 samples including shrimps, crabs, fish, shellfish and raw food sampled in restaurants, comprehensive markets for fish and meat and supermarkets as well. Twenty - eight strains of Vibrio parahaemolyticus were molecularly subtyped by PFGE with the application of restriction endonuclease Not Ⅰ and patterns obtained were subject to cluster analysis with BioNumerics Version 4. 0 software（ using Dice co- efficient and UPGMA）. Results： 57 of all 168 samples were Vibrio parahaemolyticus positive, with the detection rate being 33.93%. Among them, shellfish had the most highest carrier rate（55.56% ） , followed by shrimps, crabs and fish with no statistically significant difference between them （ P 〉 0.05 ）. Twenty - seven pulsotypes existed among twenty - eight stains, grouped into seven clusters （ Ⅰ , Ⅱ, Ⅲ, Ⅳ, Ⅴ, Ⅵ and Ⅶ ）, with the similar co -efficient no more than 77.4%. Conclusion： There is high degree of contamination by Vibrio parahaemolyticus in seafood of Guangzhou area and sanitary administrations are advised to take effective measures to prevent food - borne diseases caused by Vibrio parahaemolyticus from happening. Additionally, there was no correlation between PFGE results and the kinds of seafood, sampling time and spots, indicating that epidemiological trend did not exist in Vibrio parahaemolyticus in local seafood.