Characterization of Vibrio parahaemolyticus obtained from environment and cases of foodborne disease in Shenzhen, during 2006-2008

Abstract:

Abstract: [Objective] To analyze the serological and genetic divergence in the Vibrio parahaemolyticus from environment and cases of foodborne disease, and to compare these two groups in terms of virulence and other biological traits. [Methods] Serotyping, multi-PCR, and pulse-field gel electrophoresis (PFGE) were carried out. [Results] The main serotypes of cases isolates were O3:K6 (40.8%), O1:KUT (7.1%), O4:K8 (7.1%), and the main serotypes of environmental isolates were O3:KUT (14.2%),O1:KUT (11.4%) and O2:K3 (11.4%）. No O3:K6 strain was isolated from environment. Most cases isolates were tdh positive and trh negative, which account for 83.6%, while most environmental isolates were tdh negative and trh negative, which account for 88.5%. PFGE indicated that Clone P1 was the dominant clone cluster, including serotype O3:K6 (29 isolates), O4:K68 (4 isolates）, O11:K36 (3 isolates), O1:K25 (2 isolates), and these strains were all obtained from cases of foodborne disease. No dominant clone cluster was found in environmental isolates. [Conclusions] V. parahaemolyticus from cases of foodborne disease in Shenzhen mostly were hemolytic, tdh positive and trh negative，there were dominant PFGE type in cases isolates, the main serotype was O3:K6, while environmental isolates mostly were non-hemolytic, tdh negative and trh negative, no dominant PFGE type was found.