Occurrence of the three major Vibrio species pathogenic for human in seafood products consumed in France using real-time PCR
Abstract
Vibrio spp. have emerged as a serious threat to human health worldwide. Vibrio parahaemolyticus, Vibrio cholerae and Vibrio vulnificus are of particular concern as they have been linked to gastrointestinal infections and septice-mia associated with the consumption of raw or undercooked seafood. We developed hydrolysis probe-based real-time PCR systems with an internal amplification control for the detection of these species. We applied these systems to a total of 167 fresh or frozen crustacean, fish and shellfish samples consumed in France. Of them, 34.7% (n = 58) were positive for Vibrio. V. parahaemolyticus was the most common, in 31.1% of samples, followed by V. vulnificus in 12.6% and V. cholerae in 0.6%. Furthermore, V. parahaemolyticus and V. vulnificus were present simultaneously in 9.6% of samples. Virulence genes (tdh and trh sequences) were present in 25% of the V. parahaemolyticus-positive samples. The V. cholerae strain detected was non toxigenic. The densities of V. parahaemolyticus and V. cholerae ranged from b10 2 to 10 4 bacteria/g of seafood. All samples positive for V. vulnificus displayed low-level contamination with fewer than 10 2 bacteria/g. Our findings indicate that seafood consumption presents a potential risk to human health in France and highlight the importance of tools for a preventive consumer protection policy.