Yersinia enterocolitica infection causes the disease yersiniosis. Infection with Y. enterocolitica (family: Enterobacteriaceae) can cause a variety of symptoms depending on the age of the person infected and occurs most often in young children. 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. In a small proportion of cases, complications such as joint pains, skin rash, or spread of bacteria to the bloodstream can occur.