Multiple Canadian public health agencies are currently investigating an outbreak of the gastrointestinal infection, vibriosis, caused by Vibrio parahaemolyticus that has sickened nearly 70 in the western provinces of Alberta and British Columbia.

Public domain image/Daderot
Public domain image/Daderot

According to the investigation, a total of 67 cases have been reported in British Columbia (48) and Alberta (19). One case has been hospitalized. No deaths have been reported.

Individuals became sick between June 1 and August 7, 2015 and all reported consumption of raw shellfish, primarily oysters. The investigation is ongoing to determine the source and distribution of these products.

Health officials say The risk to Canadians is low, and illnesses can be avoided if shellfish are cooked before being eaten. People with weakened immune systems, young children, pregnant women and older adults are at increased risk for developing complications if they get sick.

Vibrio parahaemolyticus is a bacterium in the same family as those that cause cholera. It lives in brackish saltwater and causes gastrointestinal illness in humans. V. parahaemolyticus naturally inhabits coastal waters in the United States and Canada and is present in higher concentrations during summer.

V. parahaemolyticus causes watery diarrhea often with abdominal cramping, nausea, vomiting, fever and chills. Usually these symptoms occur within 24 hours of ingestion. Illness is usually self-limited and lasts 3 days. Severe disease is rare and occurs more commonly in persons with weakened immune systems.

Canadian health officials say foods contaminated with Vibrio may look, smell and taste normal.
The following safe food practices will reduce your risk of getting sick from Vibrio and other foodborne illnesses.

  • Do not eat raw shellfish.
  • Cook shellfish thoroughly before eating, especially oysters. Shellfish should be cooked to a safe internal temperature of 74°C (165°F).
  • Discard any shellfish that do not open when cooked.
  • Eat shellfish right away after cooking and refrigerate leftovers.
  • Always keep raw and cooked shellfish separate.
  • Avoid eating oysters, or other seafood, when taking antacids as reduced stomach acid may favour the survival and growth of Vibrio species.
  • Always wash your hands for 20 seconds with soap after using the bathroom.
  • Avoid exposing open wounds or broken skin to warm salt or brackish water, or to raw shellfish. Wear protective clothing (like gloves) when handling raw shellfish.
  • Wash your hands well with soap before handling any food. Be sure to wash your hands, cutting boards, counters, knives and other utensils after preparing raw foods.

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