A norovirus outbreak that is associated with raw oysters has been reported in British Columbia, according to the British Columbia Centre for Disease Control (BCCDC). Officials are warning consumers to avoid eating raw oysters to stop this outbreak.
Norovirus is a highly contagious disease that causes symptoms of food poisoning. Since early March 2018, about 40 cases have been reported to public health authorities. All of those sickened said they ate raw oysters from British Columbia before they got sick. Lab testing has confirmed that the pathogen responsible for some of those cases is norovirus.
In order to kill this virus and other pathogens, the BCCDC recommends that consumers cook oysters thoroughly, to an internal temperature of 90°C (194°F) for 90 seconds.
Two oyster farms that are implicated in this outbreak have been closed by authorities. This is not the first norovirus outbreak associated with raw oysters in Canada. In late 2016 and early 2017, 347 norovirus illness were reported in British Columbia, Alberta, and Ontario. That outbreak ended in April 2017.
Officials have not identified the precise source of the contamination. but they think that human sewage dumped into the marine environment is the most plausible cause of the contamination. Oysters are filter feeders – they take up water and filter out nutrients. That’s how they take up the virus, which then concentrates in the oyster’s body.
The symptoms of a norovirus infection include diarrhea and vomiting. If you have eaten oysters and have been experiencing these symptoms, call BC HealthLink at 811. If symptoms are severe, see your doctor. Oyster-related illnesses can also be reported to your local health authority.
Most people recover on their own after a norovirus infection. Make sure that you stay hydrated and rest. To prevent the spread of this illness, it’s important to wash your hands thoroughly with soap and water after using the bathroom, changing diapers, or taking care of someone who is sick. If you are sick, especially if you have diarrhea, stay home from work and school. Food handlers and healthcare providers should stay home until at least 48 hours after symptoms have ended.
