About Yersinia Infection

Key points

  • Yersinia are bacteria (germs) that can make you sick.
  • Infection with Yersinia is often linked to eating raw or undercooked pork.
  • Symptoms depend on the age of the person with the infection.
A three-dimensional oblong-shaped Yersinia enterocolitica bacteria.


Yersinia are bacteria (germs) that can make people ill.

Two kinds of Yersinia can cause diarrhea. They are:

  • Yersinia enterocolitica
  • Yersinia pseudotuberculosis

The illness these kinds of Yersinia can cause is called yersiniosis.


This site focuses on yersiniosis and the kinds of Yersinia that cause it. To learn about Yersinia pestis and the disease it causes, visit CDC's plague website.


People can get infected after swallowing Yersinia. Children are more likely to get Yersinia infection than adults.

Common causes of infection

  • Contaminated food, especially raw or undercooked pork
  • Contact with a person who has prepared a pork product, such as chitlins

Keep in mind‎

Germs can spread from hands to infants and toddlers. If you've been preparing food, be sure to wash your hands well before touching a child or a child's bottles, pacifiers, or toys.

Less common causes of infection

  • Drinking contaminated milk or untreated water
  • Contact with animals, their environments, or their poop
  • Contact with another person (for example, by not washing hands thoroughly after changing the diaper of a child with an infection)


Symptoms depend on the age of the person with Yersinia infection.

Symptoms in young children

  • Fever
  • Pain in the abdomen (belly area)
  • Diarrhea that can be bloody

Symptoms in older children and adults

  • Fever
  • Pain on the right side of the abdomen

Sore throat also can occur, particularly in children.

Note: The pain might be confused with an inflamed or infected appendix (appendicitis).


Infection is diagnosed by a laboratory test.



People with diarrhea should drink plenty of fluids to prevent dehydration. Dehydration is not having enough water in the body.

Dehydration can happen quickly in young children. Give children with diarrhea or vomiting extra fluids, such as Pedialyte, or oral rehydration salts. Do not wait.

Anti-diarrheal medication

  • Talk to your healthcare provider before taking anti-diarrheal medication, such as Imodium®.*
  • Do not use anti-diarrheal medication with bloody diarrhea.
  • Do not use medication containing bismuth with children younger than 12. Medications with bismuth include Pepto-Bismol® and Kaopectate®.*



Most people with Yersinia infection get better without using antibiotics.

Antibiotics are sometimes used to treat severe illness caused by Yersinia infection. But most people, including young children, recover without antibiotic treatment.

Should I call the doctor?

Contact your healthcare provider if you or your child has:

  • Diarrhea or vomiting lasting more than 2 days
  • Bloody poop or pee
  • A fever higher than 102°F
  • Signs of dehydration, which include:
    • Little or no peeing
    • Having very dark pee
    • Being very thirsty
    • Having a dry mouth or throat
    • Feeling dizzy or lightheaded
    • Crying without tears

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