Raw B.C. oysters associated with jump in norovirus cases, health officials warn

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Health officials are warning the public about an increase in norovirus cases that's been associated with eating raw B.C. oysters.

More than 50 people suffered "acute gastrointestinal illness" this week after ingesting raw oysters, Vancouver Coastal Health said in a news release Friday.

Testing has already confirmed the presence of norovirus in some of the cases, and it's suspected in others, according to the health authority.

A number of oyster-harvesting areas have been temporarily shut down following an investigation by government authorities and the shellfish industry. They will be reopened "when contamination is cleared," officials said.

In the meantime, the public has been warned against eating raw oysters.

"To kill norovirus and other germs, it is recommended to cook oysters thoroughly, to an internal temperature of 90 degrees Celsius for 90 seconds before eating," Vancouver Coastal Health said in its news release. "Avoid cross-contamination of other foods during preparation and eat shellfish immediately after cooking."

The B.C. Centre for Disease Control has also issued a notice to restaurants and retailers who serve or sell oysters in the province. For now, businesses are still allowed to serve or sell the oysters, but officials have recommended that they "inform customers about (the) risk of consuming raw oysters so they can make an informed decision."

Customers who accept the risk and order raw oysters can help the government's tracking by remembering the variety of oyster they ate, the BCCDC said. Anyone who experiences an illness they believe to be related to oyster consumption is asked to contact Vancouver Coastal Health by calling 604-675-3800, or by emailing [e-mail].

Symptoms of norovirus include nausea, cramping, chills, fever, vomiting and diarrhea, and generally emerge between 12 and 48 hours after exposure.