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What is Yersiniosis?

Yersinia is a bacteria that causes acute watery diarrhea, fever, vomiting, headache and severe abdominal pain that mimics the pain associated with appendicitis.  Symptoms can occur no sooner than 24-36 hours and often occur 3-7 days after having contact with the bacteria.  The illness can last from 1-3 days.  Infants and young children account for about two thirds of all cases and the illness is far more severe.

How is Yersinia Spread?

Yersiniosis can occur after eating, drinking or touching something contaminated with Yersinia bacteria.  The bacteria must be ingested.  The bacteria can also pass from person to person through unwashed hands.  The bacteria is passed onto the hands through the faeces and if hands are unwashed, the bacteria will be transferred to foods or objects and then passed onto another person. Any raw animal food (meat, poultry, raw milk, fish and shellfish) may carry Yersinia.  If these foods are not properly cooked, these bacteria may survive and cause illness when the food is eaten.  However, swine is the most important source for Yersinia bacteria.  They carry the organism in the backs of their throats.  They do not usually have any symptoms so there is no way to tell which pigs carry it.  Therefore all pork should be cooked thoroughly.  Hands should always be washed after handling livestock.  Yersinia can cause illness in some animals, especially puppies and kittens.

How is Yersiniosis Prevented?

• Thorough hand washing is the best prevention.  Make sure hands are properly washed after using the toilet, handling diapers, pets, livestock or before preparing foods.
• Clean and sanitize counter tops and utensils after contact with raw meat and poultry.  This is especially important before using these areas to prepare ready-to-eat foods.
• If possible use separate work areas and utensils for preparing raw and cooked foods.
• Cook meat and especially pork products thoroughly.
• Drink only pasteurized milk.  Never let youngsters sample raw milk straight from the animal.
• Keep cold foods at 4°C or lower.
• Keep hot foods at 60°C or higher.
• Drink water from a safe supply.  Have well water tested to ensure it is safe to drink.
• If ill with diarrhea, avoid preparing or handling food.
• Wash your hands after handling your pets, especially sick puppies and kittens.

Sources:  Canadian Institute of Public Health Inspectors (CIPHI) fact sheet

               Control of Communicable Diseases Manual, 18^th Edition; Heyman, David; 2004

               Centers for Disease Control and Prevention (CDC) fact sheet; October 25, 2005