So far this year, 24 cases of gastrointestinal illnesses in Ontario have been traced to raw or undercooked oysters.
Dr. David McKeown, the province’s acting chief medical officer of health, said Thursday that the illnesses in question all showed symptoms similar to those of Norovirus.
Cooking oysters at an internal temperature of 90 Degrees Celsius (194 Degrees Fahrenheit) for a minimum of 90 seconds should eliminate norovirus and other potentially harmful microorganisms.
Foodborne outbreaks of norovirus illness can occur when food is contaminated with the virus. Some foods can be contaminated at the source. Shellfish such as oysters can become contaminated from the water before they are harvested.
The common symptoms of gastrointestinal illness are nausea, vomiting, diarrhea and stomach cramps. In most healthy people, acute diarrhea and vomiting should resolve in one to two days. Symptoms may last longer in some people. Anyone experiencing these symptoms after eating oysters should seek the advice of their health care provider.”