副溶血性弧菌流行特征及毒力基因分析

Analysis on virulence genes and epidemiological characteristics of Vibrio parahaemolyticus

目的分析深圳市罗湖区副溶血性弧菌主要流行特点及毒力基因特征,为评价辖区中不致病性副溶血性弧菌引起食源性疾病暴发风险提供依据。方法 2004-2014年,从病人、食品及外环境分离到285株副溶血性弧菌,按GB/T4789.7-2013进行分离鉴定、血清学分型,采用PCR方法检测毒力因子(tdh、trh)和系统性毒力基因(tox RS/new),通过Bio Numerics软件对PFGE图谱进行聚类分析。结果辖区副溶血性弧菌血清型以O3(56.7%)、O4(24.4%)和O1(14.4%)群为主,病人(包括食物中毒病人和住院病人)中分离到的副溶血性弧菌主要是大流行株(117/160),其基因组含有毒力因子(tdh)和系统必毒力毒因(tox RS/new);食品和外环境中分离到的副溶血性弧菌主要是不致病株(112/114),其基因组无毒力因子(tdh/trh)。结论辖区副溶血性弧菌主要流行株为O3∶K6血清型及其克隆株(O3∶K6,O4∶K8,O1∶K56等),辖区存在不致病性副溶血性弧菌引发食源性疾病暴发风险。

Objective The objective of this research was to analyze the epidemiological characteristics and virulence genes of V.parahaemolyticus in Luohu district,Shenzhen,and provide the scientific basis for the risk of foodborne disease outbreaks caused by nonpathogenic V.parahaemolyticus strains. Methods 285 V.parahaemolyticus strains were isolated from patients, foods and environment in 2004-2014. The strains were identified and serotyped according to GB / T4789.7-2013. The virulence factors（tdh and trh） and systematic functional pandemic-strain-specific gene（tox RS / new） were determined by PCR. The Cluster of PFGE patterns was analyzed by Bio Numerics software. Results O3（57.6%）, O4（24.4%） and O1（14.4%） were predominant serogroups in the district. The pandemic strains（117 / 160） were the main strains isolated from patients（including food poisoning patients and inpatients）. The nonpathogenic strains（112 / 114）were the main strains isolated from foods and environment. Conclusion The O3 ∶K6 clones（O3 ∶K6, O4 ∶K8, O1 ∶K56,and so on） of V.Parahaemolyticus were the main strains found in Luohu district. There is a risk of foodborne disease outbreaks caused by nonpathogenic.