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What is yersiniosis?

Yersiniosis is an infection caused by bacteria.  The infection is an uncommon cause of diarrhea and abdominal pain.

Where are the Yersinia bacteria found?

Animals are the main source of the Yersinia bacteria. Fecal (stool) waste from animals (particularly pigs) may contaminate water, milk and foods to become a source of infection for people or other animals.

Who gets yersiniosis?

Any person can get yersiniosis but it occurs most often in children.

What are the symptoms of yersiniosis?

Infected people may experience abdominal pain, fever and watery diarrhea that may contain blood. An appendicitis-like syndrome (fever, abdominal pain, tenderness in the right lower quadrant of the abdomen) can occur primarily in older children and young adults. Complications are rare and can include skin rash, joint pains, or spread of bacteria to the blood.

How soon do symptoms appear after exposure to Yersinia bacteria?

Symptoms generally appear 4 to 7 days after exposure, and may last 1 to 3 weeks or longer.

How do Yersinia bacteria spread?

Yersinia infection spreads when a person eats or drinks contaminated food (most often undercooked pork products or unpasteurized milk) or untreated water.  In addition, direct or indirect contact with fecal (stool) material from an infected person or animal can also spread Yersinia. Babies and infants can be infected if their caretakers handle contaminated food and then do not wash their hands properly before handling the child or the child's toys, bottles, or pacifiers.

How long can an infected person carry Yersinia?

The bacteria can be found in feces (stool) of infected persons when they have symptoms and in some cases for a few weeks to months afterward. For this reason, it is important for infected people to thoroughly wash their hands after each toilet visit.

How is yersiniosis treated?

Most people infected with the bacteria get better on their own without treatment. Those with severe symptoms can be treated with antibiotics.

How can yersiniosis be prevented?

Avoid drinking contaminated water and raw (unpasteurized) milk.  Cook meat thoroughly, especially pork and pork products (including chitterlings) to an internal temperature of 150 °F. Practice good hand washing after handling animals, especially domestic pets.  People handling and preparing food (especially pork) should wash their hands often after contact with the food. Carefully clean all cutting boards, countertops, and utensils with soap and hot water after preparing any food.​

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