Occurrence of Vibrio parahaemolyticus in oysters (Crassostrea gigas) and mussels (Perna perna) of the seacoast of Santa Catarina, Brazil

This research aimed to identify and quantify Vibrio parahaemolyticus in fresh oysters (Crassostrea gigas), mussels (Perna perna) and seawater from different regions of cultivation of bivalve shellfishes in the seacoast of Santa Catarina, Brazil. Samples were collected between October 2012 and December 2013 and 130 oysters samples (Crassostrea gigas), 215 mussels samples (Perna perna) and 222 seawater were collected. The occurrence of V. parahaemolyticus in oysters and mussels was low, 10.76 and 11.62% of the samples tested. Higher incidences of V. parahaemolyticus were observed in seawater (18%). The density of V. parahaemolyticus in summer (December to March) was significantly greater than those in the other 3 seasons (P < 0.01). The occurrence of pathogenic V. parahaemolyticus in oyster, mussels and seawater was very low (<10%). It is recommend that control measures should be considered, including the establishment of an intensive and continuous monitoring of potentially pathogenic V. parahaemolyticus from all oyster-growing areas, the environmental parameters, and the assessment of the region-specific human health risk due to consumption of oyster.