Two Vancouver Island oyster farms have been closed following an outbreak of norovirus associated with eating the raw shellfish.
The British Columbia Centre for Disease Control says about 40 cases of acute gastrointestinal illness have been connected to the consumption of raw oysters since March. Testing has confirmed some of the cases were norovirus.
While the two farms are no longer harvesting oysters for consumption, no recall of oysters has been issued by the Canadian Food Inspection Agency.
While the precise sources of contamination have not been identified, human sewage in the marine environment is currently believed to be the most plausible cause of shellfish contamination, according to BCCDC epidemiologist Marsha Taylor.