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  • Mesa County Public Health (MCPH) recently investigated a case of vibriosis, infection with the bacteria Vibrio parahemolyticus, in a Mesa County resident who had eaten raw oysters.
    • The most recent case of vibriosis in Mesa County prior to this investigation was in 2016.
  • Vibriosis, particularly Vibrio parahemolyticus, is caused by eating raw or under-cooked oysters and other shellfish or when an open wound comes in contact with raw seafood juices or contaminated coastal waters.
  • Risk of vibriosis increases from May through October because higher temperatures support the growth of the bacteria that oysters, clams and mussels filter from the warmer waters as they feed.
  • An oyster that contains the bacteria doesn’t look, smell, or taste different from other oysters. The only way to kill the harmful bacteria in oysters is to properly cook them.
    • The cook temperature for oysters is 145°F. Your thermometer should be able to hold 145°F for 15 seconds total.
    • Even if raw oysters are properly stored and handled by food workers, they can still make you sick.
  • Although risk increases from May through October, anyone can become infected with this disease at any time of the year.
  • Symptoms of vibriosis occur within 24 hours of ingestion and can last up to three days. Intestinal vibriosis symptoms include:
    • runny diarrhea,
    • vomiting,
    • abdominal cramping,
    • fever and chills, and
    • wound infections from contact with contaminated water can be very serious and even fatal.
  • Contact your health care provider if you develop symptoms after handling or eating raw shellfish.
  • Reduce your risk of this disease by:
    • Fully cooking raw oysters or other shellfish. If oysters don’t open after fully cooking, throw them away.
    • Washing your hands after handling raw seafood.
    • Covering any wounds while handling raw seafood.
    • Washing the wound with soap and water if you’ve been in contact with raw seafood or its juices.
    • Staying out of coastal river waters if you have open wounds or low immunity.