64 cases of 'norovirus-like' illness linked to raw oysters in B.C., officials say

Dozens of people have become ill after eating raw oysters in B.C. since Nov. 1, public health officials warned Thursday.

The Provincial Health Services Authority and the B.C. Centre for Disease Control said in a statement that 64 cases of "norovirus-like gastrointestinal illness" have been reported in the Vancouver Coastal, Fraser and Island health authorities between Nov. 1 and Wednesday.

"Those affected have reported symptoms of diarrhea, vomiting, and/or stomach pain after eating raw oysters from restaurants and retail locations," the agencies said.

"While some individuals have visited emergency departments, there have been no hospital admissions reported."

According to the statement, the BCCDC and regional health authorities are investigating the illness reports with help from federal partners.

"As part of this investigation, federal agencies have closed some areas to commercial shellfish harvesting, including areas in Baynes Sound, west of Denman Island," the statement reads.

People who harvest shellfish recreationally should check the BCCDC shellfish map for detailed information about site closures, officials said. 

"Norovirus is a common cause of gastrointestinal illness, especially during the winter months," the statement reads. "Symptoms usually begin 12 to 48 hours after infection and can include nausea, vomiting, cramps, fever and diarrhea."

While symptoms can be intense and generally last between 24 and 72 hours, most infections are mild and pass without medical intervention, officials said, adding that the greatest risk is fluid loss or dehydration, especially for seniors and the very young.

People suffering from norovirus or other similar gastrointestinal illness are encouraged to drink lots of fluids to stay hydrated.

Norovirus spreads easily from person to person. It can also be acquired through consumption of food or water contaminated with the virus.

Health officials advise against consuming raw or undercooked shellfish, saying norovirus can be killed in oysters by cooking them to an internal temperature of 90 C for 90 seconds.

More information about norovirus can be found through HealthLinkBC.