宁波地区环境中副溶血弧菌血清学及毒力相关基因研究

目的 了解宁波地区环境来源海产品中副溶血弧菌血清学特点及毒力相关基因分布。方法 采集并分离2013年6‒10月宁波地区海产品中副溶血弧菌，对其进行O、K抗原血清学分型；并采用PCR或多重PCR的方法来检测溶血素基因（tlh、tdh、trh）、大流行群遗传标志基因（toxRS/new、orf8）和Ⅲ型分泌系统（T3SS1、T3SS2α、T3SS2β）基因。结果 从海产品样本中分离鉴定到44株副溶血弧菌的菌株，分属于20种血清型，型别多样，未见优势血清型；溶血素基因检测发现3株tdh+trh-致病性菌株，遗传标志基因检测发现1株tdh+trh-toxRS/new+大流行株，其血清型为O3:K6型；Ⅲ型分泌系统基因检测发现T3SS1基因存在于所有的副溶血弧菌菌株中，而T3SS2α基因则主要分布在tdh+的菌株中。结论 宁波地区环境中副溶血弧菌致病性菌株和大流行株的检出，说明该地区具有潜在的食源性疾病爆发的风险。

Serology and virulence-associated genes of environmental Vibrio parahaemolyticus strains circulating in Ningbo

Objective To explore the serological characteristics of of environmental Vibrio parahaemolyticus strains circulating in Ningbo and the distribution of its virulence-associated genes. Methods O and K antigen determination were conducted on the environmental Vibrio parahaemolyticus strains isolated from Ningbo from June to October, 2013. The isolates were tested for the presence of haemolysin genes (tdh, trh) and pandemic markers (toxRS/new, orf8) by using conventional monoplex PCR, and the type III secretion system (T3SS1, T3SS2α, T3SS2β) by using conventional four-multiplex PCR, respectively. Results A total of 44 strains of Vibrio parahaemolyticus were isolated from sea food samples, which spanned 20 serogroups with no predominant serotype found. Pathogenic strains harboring tdh+trh- gene marker were observed in three strains. Only one pandemic strain harboring tdh+trh-toxRS/new+ gene marker was found, the serogroup of which was assigned to O3:K6. T3SS1 gene was identified in all the Vibrio parahaemolyticus strains, whereas the T3SS2α gene was mostly identified in tdh+ strains. Conclusion The identification of pathogenic strains and pandemic strains of environmental Vibrio parahaemolyticus indicates that the region is in potential risk of foodborne disease outbreaks.