崇州市23株副溶血弧菌的病原特征分析

Analysis of the Pathogenic Characteristics of 23 Vibrio Parahaemolyticus Isolates From Food-poisoning Events in Chongzhou

目的分析四川崇州地区2014-2017年6起23株副溶血弧菌食物中毒疫情分离株毒力基因携带,耐药及分子分型特征,为该地区副溶血性弧菌疾病防治提供科学依据。方法采用微量肉汤稀释法(MIC)检测13种抗生素的敏感性;实时荧光PCR法检测(tdh、trh)毒力基因;脉冲场凝胶电泳(PFGE)和Bio Numerics软件对菌株进行分子分型分析。结果 23株副溶血性弧菌PFGE聚类分析共分为18个型别。2起暴发的病人之间分属同一PFGE型别,其余4起暴发病人、食品、环境之间相关性均低于60%;2起暴发病人分离株存在100%相似的带型。食品和环境分离株无毒力基因检出,病人分离株毒力基因检出率88.89%(16/18)。食品环境分离株对头孢唑啉100%(5/5)耐药,对其他12种药物均敏感;临床分离株对氨苄西林27.78%(5/18)耐药、头孢唑啉100%(18/18)耐药,对其他11种药物均敏感。结论该地区近年来由副溶血性弧菌引起的食物中毒事件存在由多种不同型别和相同型别(PFGE带型100%相似)弧菌引起情况。

Objective To analyze the characteristics of virulence genes carrying,drug resistance and molecular typing 23 Vibrio parahaemolyticus isolates from six food poisoning outbreaks in 2014-2017 in Chongzhou.Methods Susceptibilities to 13 antibiotics were determined by broth microdilution method; tdh and trh genes were detected by real-time fluorescent PCR method; molecular typing of strains was analyzed by pulse field gel electrophoresis（ PFGE） and Bio Numerics software. Results A total of 18 banding types were identified in the23 Vibrio parahaemolyticus isolates by PFGE typing. The band patterns of some strains from the same outbreaks were completely identical,and two outbreaks belonged to this situation. The band patterns of most isolates were different,and the correlation of the rest four outbreaks between the patients,the remaining food and the environment was less than 60%. The isolates from different outbreaks showed the same PFGE type. Non virulence genes were detected in food and environmental isolates. The positive rate of virulence gene carrying of the isolates of the patients was 88. 89%（ 16/18）. All the 23（ 100. 00%） isolates were resistant to cefazolin and 27. 78%（ 5/18） of isolates from patients were resistant to ampicillin. Conclusion There were multiple band patterns in isolates from the same outbreaks. The isolates from the different outbreaks in different ages have the same PFGE type.