Abstract:Objective To investigate the source of a food poisoning case in a rural wedding banquet based on the PFGE analysis of the pathogenic bacterium isolated from the patient anal swabs and polluted external environment samples. Methods Etiological examinations of 20 specimens were performed. Serological typing, pulsed-field gel electrophoresis (PFGE) analysis and tdh, trh, tlh, toxR genes test were carried out on the Vibrio parahaemolyticus (VP) detected. Results Fifteen strains of VP were isolated from 20 samples. Gene tests showed that 11 specimens were tdh, tlh, toxR genes positive, while 4 were tlh, toxR genes positive. Nine out of 12 patient anal swab samples were VP positive, of which 7 were O3∶K6 serotype, while the remaining were O2 group; All 3 chopping block daub samples were VP positive, of which 2 were O3∶K6 serotype, the third one was O1 group; 2 out of 3 remaining foods were VP positive, which were O1, O10 group respectively. The anal swab sample of the chef was O11 group positive. PFGE analysis revealed that the O3∶K6 of the patient anal swabs and chopping block daub samples were highly homologous. Conclusion This was a food poisoning outbreak caused by multiple serotypes of VP mainly by O3∶K6, which might be contaminated through chopping block.