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

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 O4: K8 Vibrio parahaemolyticus,of which 5 samples were also positive for O3: 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 O4: K8 serotype and the O3: K6 serotype.