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Occurrence of the tdh and trh genes in Vibrio parahaemolyticus isolates from waters and raw shellfish collected in two French coastal areas and from seafood imported into France.

Unité du Choléra et des Vibrions, Centre National de Référence des Vibrions et du Choléra, Institut Pasteur, 25, rue du Dr Roux, 75 724 Paris 15, France.
International Journal of Food Microbiology (Impact Factor: 3.43). 04/2004; 91(3):319-25. DOI: 10.1016/j.ijfoodmicro.2003.07.006
Source: PubMed

ABSTRACT The occurrence of the hemolysin genes, tdh and trh, in Vibrio parahaemolyticus strains isolated from environmental samples collected in two French coastal areas, clinical samples, and seafood products imported into France was studied. Polymerase chain reaction (PCR) with two sets of primers was used to detect the hemolysin genes. Most of the clinical isolates (91%) and 1.5% of the isolates from seafood possessed the hemolysin genes. Three and fifteen percent, respectively, of the two groups of environmental strains carried the hemolysin genes depending on the geographic site. The tdh and trh genes play important roles in virulence. Thus, our results indicate that pathogenic V. parahaemolyticus isolates are present in French coastal areas and in seafood imported into France. Furthermore, they may also be present in French seafood products.

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