一起两种血清型副溶血性弧菌食物中毒的毒力基因及分子分型研究

Research on toxin gene and molecular genotype of Vibrio parahaemolyticus with different serotypes isolated from samples of one food poisoning

目的:对一起两种血清型副溶血性弧菌引起的食物中毒病原菌进行毒力基因及分子分型研究。方法:参照WS271-2007等标准对10名病人的肛拭进行致病菌的检测,对分离的副溶血性弧菌进行血清学试验;运用荧光定量PCR检测分离菌株的毒力基因,并用脉冲场凝胶电泳(PFGE)进行分子分型。结果:10份样本均检出O4:K8血清型副溶血性弧菌,其中5份样本同时检出O3:K6血清型副溶血性弧菌。两种血清型的副溶血性弧菌毒力基因检测均为tdh阳性、trh阴性。PFGE分型显示,同一血清型的菌株为高度相似克隆,相似度在92.9%～100%之间,同一样本不同血清型的菌株为不同克隆。结论:这是一起由O4:K8和O3:K6两种血清型副溶血性弧菌混合感染引起的食物中毒。

Objective ：To analyse the toxin genes and molecular genotype of Vibrio parahaemolyticus with two kinds of serotypes isolated from samples of one food poisoning. Methods： The isolation and identification of pathogen from swab anal were conducted according to WS271 -2007 etc. Then serological test was done on the isolated Vibrio parahaemolyticus, fluorescence quantitative PCR was used to detect the toxin gene, and PFGE was used for molecular typing. Results： All the 10 samples were positive for 04 ： K8 Vibrio parahaemolyticus, of which 5 samples were also positive for 03 ： K6 Vibrio parahaemolyticus. Toxin gene detection of Vibrio parahaemolyticus of two serotypes were tdh positive, trh negative. PFGE typing showed that strains of the same serotype were highly similar, and the similarity was from 92.9% to 100%, while strains from the same sample of different serotypes were different clones. Conclusion： This food poisoning was caused by coinfecion with two serotypes of Vibrio parahaemolyticus： the 04：K8 serotype and the 03：K6 serotype.