Survival of Vibrio parahaemolyticus in presence of chlorine

Vibrio parahaemolyticus is well recognised as the causative agent of gastro enteritis associated with seafood consumption. The concentration and contac t time required by the commonly used sanitizer, hypochlorite for killing/ r educing the cells of V. prrrahaemolyticus in phosphate buffered saline (PBS ) and in association with fish was studied. A minimum level of 0.5 ppm of a vailable chlorine was able to reduce the count of both Kanagawa positive (K +) and Kanagawa negative (K-) V.parahaemolyticus in PBS by 90% within 5 min and complete killing of both was achieved in 20 and 30 min, respectively. In fish artificially contaminated with K + V.parahaemolyticus and exposed t o 10 and 20 ppm available chlorine, complete destruction of the cells was o bserved in 10 min. but at 30 ppm level, the time required was only 5 min. H emolytic activity of the K + V.parhaemolyticus was not affected by chlorine treatment.