As outdoor temperatures increase, so does the risk of illnesses associated with eating raw or undercooked bivalve shellfish, such as oysters, clams, mussels, scallops, and cockles.

 The B.C. Centre for Disease Control is reminding British Columbians that Vibrio parahaemolyticus, a naturally occurring bacterium found in shellfish that causes illness, is present in higher concentrations during the summer months when water temperatures rise.

 In 2008, B.C. had 23 cases infected with Vibrio parahaemolyticus, an illness linked to raw oysters served in restaurants, bought at retail outlets or self-harvested raw shellfish, in communities throughout the province.

Last month, the province recorded four cases of Vibrio parahaemolyticus, with all individuals infected having eaten shellfish at a restaurant or self-harvested shellfish at home.

 “People who eat raw oysters in restaurants, buy them from retail outlets or harvest oysters themselves need to be aware of the potential health risks,” said Dr. Colette Gaulin, physician epidemiologist with the B.C. Centre for Disease Control, an agency of the Provincial Health Services Authority.

“Consuming raw or undercooked shellfish can cause severe diarrhea and vomiting that can last up to a week.” 

 To reduce the risk of illness, consumers are advised to keep shellfish cool by refrigerating immediately after purchase, carefully read label instructions, use drinking-quality water to rinse ready-to-eat shellfish and only purchase live shellfish from approved sources.

All bivalve shellfish sold to the public in B.C. must have a shellfish shipper’s tag, which ensures federal inspection.