Animals are the main source of yersinia. Fecal wastes from animals may contaminate water, milk and foods and become a source of infection for people or other animals. The germ has been found in raw milk, lakes and streams, ice cream, improperly pasteurized chocolate milk, tofu, shellfish and wild and domestic animals. The germ is passed in the feces during the time the person is experiencing diarrhea and in some cases for a few weeks or months afterward. For this reason, infected people must be very careful to thoroughly wash their hands after each toilet visit.
Most cases recover on their own without treatment.
Those with severe symptoms or bloodstream infections are generally treated with antibiotics. Avoid drinking raw milk and improperly treated surface water.