British Columbia

Norovirus cases up due to consumption of raw oysters: health authority

More than 50 people have been affected by acute gastrointestinal illness after eating raw oysters over the past week, Vancouver Coastal Health says.

Symptoms include nausea, vomiting and diarrhea

raw osyters on the half shell sit on a plate of crushed ice with a lemon wedge
The consumption of raw oysters is causing an uptick in norovirus cases in Vancouver. (Rafferty Baker/CBC)

Vancouver's health authority is warning residents of the risk of norovirus associated with eating raw oysters after a spike in cases over the past week. 

Since Monday, more than 50 people have been affected by acute gastrointestinal illness after eating raw oysters, Vancouver Coastal Health said in a statement.

Lab testing confirmed it was norovirus for some of those cases, and suspected it was present in others. 

Symptoms have included stomach pain, diarrhea and vomiting. Common symptoms of norovirus include nausea, cramping, chills, fever, vomiting and diarrhea. Symptoms often set in 12 to 48 hours after consuming raw oysters.

Anyone who experiences these symptoms is asked to call B.C.'s HealthLink line at 811, and if symptoms worsen, they are advised to seek medical attention. 

The B.C. Centre for Disease Control has also sent a notice to restaurants and retailers advising them of the risk. 

Norovirus and other germs can be killed when oysters are cooked thoroughly. Vancouver Coastal Health says they should be cooked to an internal temperature of 90 C for 90 seconds before eating, and advises against eating raw oysters.