OCCURRENCE OF POTENTIALLY PATHOGENIC VIBRIOS IN BIVALVE MOLLUSKS (MUSSELS AND CLAMS) FROM RETAIL OUTLETS IN THE NORTH OF SPAIN

Forty-three samples of shellfish (22 mussels and 21 clams) purchased from retail outlets from February through October were tested for the presence of vibrios associated with human disease. Vibrio spp, was found in 51.26% of the samples. V. alginolyticus was the commonest Vibrio species found in the samples, followed by V. parahaemolyticus, V. fluvialis and V. cholerae non-01. All V. parahaemolyticus isolated were Kanagawa-phenomenon negative. Hemolytic activities were shown in all isolates of V. fluvialis and V. cholerae. Bacterial indicators of quality and safety were within permitted limits by authorities. The results indicate the potential risks of food poisoning associated with the consumption of raw or undercooked shellfish.