Detection of an etiological agent of food poisoning:Vibrio parahaemolyticus Serovar O3∶K6

Objective The study was conducted to identify the etiological agent that induced food poisoning by analyzing the victims' stool samples and/or anal swabs,food remains,condiments,and additives and spreads used during food processing to determine its biological characteristics.Methods The isolated strains of Vibrio parahaemolyticus were subject to serotyping,drug resistance test,species-specific gene tdh(Thermostable Direct Hemolysin) and virulence gene trh(Thermostable Direct Hemolysin-Related Hemolysin) detection per GB/T4789-2006.Results A total of 74 strains of VP were isolated from 153 stool samples and/or anal swabs,and other three were found one each from condiments,food-processing spreads and food remains in trash bags.The serotyping suggested that all strains of VP were serovar O3∶K6,Kanagawa positive.Amplification of the species-specific gene from the 77 strains resulted in an identical 320 bp band.The virulence gene multi-PCR test of them suggested tdh(434 bp) positive and trh(250 bp) negative.Conclusion Vibrio parahaemolyticus Serovar O3∶K6 was the cause of food poisoning;its strong virulence was confirmed.