In a follow-up on the norovirus outbreak linked to the consumption of British Columbia raw oysters, The Public Health Agency of Canada reported today that a total of 126 cases of gastrointestinal illness linked to oyster consumption have been reported in three provinces: British Columbia (92), Alberta (9), and Ontario (25). No deaths have been reported.
Individuals became sick between mid-March and early April 2018. Individuals who became sick reported eating raw oysters from British Columbia prior to the onset of their illness. Although not all cases of illness have been tested, testing of several cases has confirmed the presence of a norovirus infection. It is suspected that norovirus illness caused by the consumption of contaminated oysters is the cause of illness in the untested cases.
Currently, oyster farms in British Columbia that have been associated with illnesses in this outbreak have been closed as a part of the investigation. These closures aim to prevent further illness.
The outbreak is ongoing, indicating that contaminated oysters remain on the market (including seafood markets, restaurants, and grocery stores). Be aware of the risks associated with consuming raw or undercooked oysters. Food contaminated with noroviruses may look, smell and taste normal. The following safe food handling practices will reduce your risk of getting sick:
- Ensure oysters are fully cooked before consuming them. Lightly cooking oysters does not kill norovirus. Oysters need to be cooked to an internal temperature of 90° Celsius (194° Fahrenheit) for a minimum of 90 seconds in order to kill norovirus.
- Discard any oysters that did not open while cooking.
- Eat oysters right away after cooking and refrigerate leftovers.
- Always keep raw and cooked oysters separate to avoid cross-contamination.
- Do not use the same plate or utensils for raw and cooked shellfish, and wash counters and utensils with soap and warm water after preparation.
- Wash your hands well with soap before and after handling any food. Be sure to clean and sanitize cutting boards, counters, knives and other utensils after preparing raw foods.