Study on serotype,virulence genes and drug resistance of Vibrio parahaemolyticus isolates from seafood in Sanya

Objective To understand the pollution levels,major serotype distribution,virulence genes and drug resistance of Vibrio parahaemolyticus in seafood. Methods Vibrio parahaemolyticus were isolated from seafood according to GB /T4789. 7-2008 for biochemical identification and serotyping. Virulence genes were tested by real-time fluorescent quantitative PCR,and the drug resistance of these Vibrio parahaemolyticus isolates were tested by KB agar disk diffusion method. Results Sixty seafood samples were found Vibrio parahaemolyticus in 208 seafood samples,and these Vibrio parahaemolyticus isolates belonged to9 serotypes. No tdh and trh genes were detected in the isolates,while tlh gene was positive in all the isolates. There were 4 serotypes in 38 Vibrio parahaemolyticus isolates from patients,which were all found carrying tlh gene,not carrying trh,and tdh was detected in 36 strains,accounting for 94. 74%. Drug susceptibility results showed 76 isolates were highly sensitive to aminoglycoside and quinolones antibiotics. Conclusion Vibrio parahaemolyticus isolates showed diverse serotype distribution in seafood of Sanya,and they were highly sensitive to aminoglycoside and quinolones antibiotics. Shellfish was seriously contaminated by Vibrio parahaemolyticus. No tdh and trh gene was detected in Vibrio parahaemolyticus isolates from seafood,and those from the patients were mainly O3 and O4 serotypes. There was no significant correlation between Vibrio parahaemolyticus isolates from the patient and seafood. Monitoring and drug resistance analysis of the Vibrio parahaemolyticus should further be strengthened.