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目的了解2015年安徽地区食品及腹泻病例粪便标本分离副溶血性弧菌的血清型及毒力基因特征,构建脉冲场凝胶电泳DNA指纹图谱库。方法采用玻片凝集法对分离自食品及腹泻病例的61株副溶血性弧菌进行血清学分型,采用Real-time PCR法检测tlh、tdh和trh毒力基因,通过脉冲场凝胶电泳(PFGE)对菌株基因组DNA进行分子分型,电泳图谱用BioNumerics 6.6软件进行聚类分析,并构建指纹图谱库。结果 61株副溶血性弧菌分为3个O群和20个K型,共23个血清型,以O3∶K6血清型为主,占26.2%(16/61)。61株副溶血性弧菌tlh、tdh和trh基因阳性率分别为100.0%(61/61)、29.5%(18/61)和0(0/61),病例分离株tdh基因阳性率为94.7%。61株菌株中有58株的基因组DNA得到有效酶切,分成50个PFGE带型,经BioNumerics6.6软件分析有5个相似系数大于80%的聚类群。其中病例株较为集中,多分布在A群和B群;食品株较为分散。病例株和食品株未聚集在同一群中。结论 2015年安徽地区分离的副溶血性弧菌有多种血清型,以O3∶K6型居多,病例分离株tdh基因携带率较高,通过构建PFGE图谱库可识别不同来源、不同区域、跨时间段菌株间的亲缘关系,为食源性疾病的溯源和暴发识别提供了依据。
Objective To understand the serotypes and virulence genes of Vibrio parahaemolyticus isolated from stool samples from food and diarrhea cases in Anhui province in 2015 and establish a DNA fingerprinting database for pulsed-field gel electrophoresis. Methods 61 strains of Vibrio parahaemolyticus isolated from food and diarrhea were screened by slide agglutination method. The virulence genes of tlh, tdh and trh were detected by Real-time PCR and analyzed by pulsed-field gel electrophoresis (PFGE ) Genomic DNA strains were molecular typing, electrophoresis using BioNumerics 6.6 software cluster analysis and construction of fingerprint library. Results 61 strains of Vibrio parahaemolyticus were divided into 3 O groups and 20 K type, a total of 23 serotypes, mainly O3: K6 serotypes, accounting for 26.2% (16/61). The positive rates of tlh, tdh and trh of 61 Vibrio parahaemolyticus were 100.0% (61/61), 29.5% (18/61) and 0 (0/61), respectively. The positive rate of tdh gene was 94.7% . 58 isolates of 61 isolates were effectively digested with 50 PFGE bands and analyzed by BioNumerics 6.6 software for 5 clusters with similarity coefficients greater than 80%. Among them, case strains were more concentrated and distributed in groups A and B; food strains were more dispersed. Case and food strains did not accumulate in the same group. Conclusions There are many serotypes of Vibrio parahaemolyticus isolated in Anhui Province in 2015, most of which are O3: K6 strains. The carrier rate of tdh gene in case isolates is high. PFGE map database can be used to identify different sources, different regions, Parasite strains of the genetic relationship, traceable source of food-borne diseases and provide a basis for outbreak identification.