Distribution of Vibrio parahaemolyticus in Marine Water, Sediments and Marine Invertebrates Collected from Rameswaram Island, Tamil Nadu, India

Samples of seawater, sediments and invertebrates like bivalve (Dona faba and Scapharca inegerivalis) and gastropod (Littorina scabra and Cerithium trailli) were collected from the bathing place, Agnitheertham (AT) and Sewage Mixing Place (SMP) of Rameswaram island from August 2006 to July 2007. A total of twelve seawater samples and twelve sediments samples and 312 marine invertebrates were analyzed to detect the occurrence of Vibrio parahaemolyticus. V. parahaemolyticus was isolated from all the samples throughout the year. No seasonal variation in the counts of V. parahaemolyticus in water, sediments and marine invertebrates was observed. Water samples of SMP showed low density of V. parahaemolyticus compared to seawater of AT. Sediments of both AT and SMP contained high counts of V. parahaemolyticus compared to water samples. Invertebrates collected from both AT and SMP showed high counts of V. parahaemolyticus, compared to other samples. Invertebrates collected from SMP showed high density of V. parahaemolyticus. Among the marine invertebrates, bivalves at both AT and SMP showed high counts of V. parahaemolyticus. Bivalves collected from SMP showed high counts of V. parahaemolyticus compared to bivalves collected from AT. Occurrences of high counts of V. parahaemolyticus in marine organisms are dependent on the nature of feeding habits and the habitats from where the animals have been collected. Proper monitoring and attention should be given to the pilgrim town, Rameswaram, otherwise marine organisms may be infected by these pathogens, which may cause health hazards to the consumers.