Yersiniosis is an infection caused by the bacteria Yersinia enterocolitica that is found in the feces of infected people and animals and in some types of food.
The time frame from ingesting the bacteria to feeling ill is call the "incubation period". Infection with Yersinia occurs most often in young children and the infection is more common in the winter. Symptoms typically develop three to seven days after exposure. Common symptoms in children are fever, abdominal pain, and diarrhea, which is often bloody. In older children and adults, right-sided abdominal pain and fever may be the predominant symptoms, and may be confused with appendicitis. Yersinia is a relatively infrequent cause of diarrhea and abdominal pain.
The major animal reservoir for Yersinia that causes human illness is pigs, although other animals including rodents, rabbits, sheep, cattle, horses, dogs, and cats, can be a reservoir.
Infection is most often acquired by eating contaminated food, especially raw or undercooked pork products. The preparation of raw pork intestines (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 transmit the infection. Occasionally Yersinia infection occurs after contact with infected animals. On rare occasions, it can be transmitted as a result of the bacteria 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. People can shed the bacteria in their stool from two weeks, up to six week after onset on illness.
Tips for preventing the spread of this illness can be found on our tips page. To reduce the potential spread of Yersinia additional control measures may be required for persons associated with high-risk activities or settings such as food handlers, childcare facilities, and health care workers. Specific guidance and recommendations can be found in a manual titled Prevention and Control of Communicable Diseases. Additional guidance for retail food establishment management can be found in Chapter 2 of the food code.
For additional information on Yersinia, please visit the following references: Centers for Disease and Control and Prevention website and FDA’s Bad Bug Book. For data on reported Yersinia cases in Missouri, visit the communicable disease data and statistical reports page for the annual reports listed there.