杭州地区2000-2002年副溶血弧菌的分子分型研究

目的了解杭州地区2000-2002年副溶血弧菌临床和环境分离菌株的分子流行病学特征.方法对172株2000年和2002年从临床食物中毒患者和散发腹泻病例以及外环境（小水产品）中分离的副溶血弧菌菌株进行血清分型.对40株临床来源O3：K6型菌株及环境来源O3：KUT（K抗原未分型）型菌株,应用PCR技术进行耐热直接溶血素基因（tdh）和耐热直接溶血素相关基因（trh）的检测,并进行核糖体基因分型（ribotyping）、随机扩增多态性DNA分析（RAPD）、肠道细菌重复基因间共同序列PCR（ERIC-PCR）等.结果在调查的13起副溶血弧菌引起的食物中毒中,tdh阳性、trh阴性的O3：K6血清型引起的有11起（84.6%）;tdh阳性、trh阴性的O4：K8菌引起有2起（15.4%）.在散发腹泻病例中,tdh阳性、trh阴性的O3：K6、O4：K8和O1：KUT菌株分别占26.5%（9/34）、17.6%（6/34）和38.2%（13/34）,未能分型的占17.6%（6/34）.在水产品中分离的菌株中,37株分属7种O血清型,其中未见有O3：K6和O4：K8血清型;另外有9株未能分型;其中除1株O1：KUT菌株trh阳性外,其余tdh和trh均为阴性.绝大部分食物中毒患者和散发腹泻病例分离的O3：K6菌株在ribotyping、ERIC-PCR及RAPD三种指纹上均属于一种密切相关的克隆群,而环境分离的O3：KUT菌株与临床分离的O3：K6菌株间,在三者指纹上均有明显差异.结论临床来源和小水产品来源的副溶血弧菌菌株间血清型分布有显著差别;一群关系密切、tdh阳性、trh阴性的O3：K6血清型菌株在杭州地区呈优势流行.

Molecular typing on Vibrio parahaemolyticus isolates from Hangzhou, China, during 2000 - 2002

Objective To study the molecular epidemiology of Vibrio parahaemolyticus isolates from clinical and environmental samples collected in Hangzhou area during 2000 and 2002. Methods V. parahaemolyticus isolates from food-poisoning, sporadic diarrhea patients and seafood in market in Hangzhou during 2000 and 2002 were serotyped. From clinical isolates of serotype O3 : K6 and environmental isolates of serotype O3 : KUT, virulence genes, tdh and trh, were examined by PCR. Molecular typings [including ribotyping, random amplified polymorphic DNA analysis (RAPD), enterobacterial repetitive intergenic consensus PCR (ERIC-PCR)], were also performed. Results Among 13 food-poisoning outbreaks caused by V. parahaemolyticus, O3 : K6 strains with tdh positive and trh negative were detected in 11 episodes (84.6 %), and O4 : K8 strains with tdh positive and trh negative were responsible for other 2 outbreaks (15.4%). In34 V. pa rahaemolyticus isolates from sporadic diarrhea patients, O3:K6, O4:K8, and O1:KUT strains with tdh positive and trh negative were detected with proportions of 26.5% (9/34), 17.6%(6/34), and 38.296(13/34), respectively, and other 6 strains were not able to be serotyped. Of 64 isolates from seafood in which both tdh and trh were negative except trh was positive in one O1: KUT strain, 37 belonged to 7 serotypes except O3: K6 or O4: K8, and 9 were not able to be serotyped. The fingprintings of ribotyping, ERIC-PCR, and RAPD showed that almost all of O3: K6 isolates from food-poisoning and sporadic diarrhea patients were genetically close to each other and there were obviously genetical difference between O3: K6 isolates from clinic and O3 : KUT isolates from environment. Conclusion There was a distinct serotype distribution between V. parahaemolyticus isolates from clinic patients and seafood. One group of close related V. parahaemolyticus O3:K6 strains with tdh positive and trh negative seemed to be prevailing in Hangzhou in those years.