Yersenia This bacteria can cause a variety of symptoms: diarrhea, fever and abdominal pain in children; right-sided abdominal pain often confused with appendicitis in adults. While infection is rare, swimmers could be exposed by swallowing water in rivers, lakes or streams or hand-to-mouth transmission. Most cases are resolved without treatment, but antibiotics can be used to treat more severe cases. The best way to avoid yersiniosis is to avoid contaminated water and to wash your hands with soap and water before eating.