The major animal reservoir for Yersinia enterocolitica strains that cause human illness is pigs. Other animals that the bacteria can be found in include:
The preparation of raw pork intestines (called chitterlings) may be particularly risky. Infants can be infected if their caretakers handle raw chitterlings and then do not adequately clean their hands before handling the infant or the infant's toys, bottles, or pacifiers. Drinking contaminated, unpasteurized milk or untreated water can also cause yersiniosis.
Occasionally, transmission occurs after contact with infected animals. On rare occasions, Yersinia enterocolitica infection is a result of the bacterium passing from the stools or soiled fingers of one person to the mouth of another person. This may happen when basic hygiene and handwashing habits are inadequate. In rare cases, infection occurs through a blood transfusion that contains contaminated blood.
When a person becomes infected with Yersinia enterocolitica, the bacteria begin to multiply. After four to seven days, symptoms can begin. The period between becoming infected and the start of symptoms is called the incubation period.
Yersinia enterocolitica symptoms can vary, depending on the age of the person infected.
Symptoms in Young ChildrenYersinia enterocolitica infections occur most often in young children. Common symptoms include:
- Abdominal pain (stomach pain)
- Diarrhea, which in 5 percent of children is bloody.
Symptoms in children may last one to three weeks or longer.