Dysentery is a painful intestinal infection usually caused by bacteria or parasites that results in abdominal pain and diarrhea. It is characterized by inflammation of the intestines, especially the colon. The two most common causes are infections with Bacillus bacteria or infestation by amoebas. Risk factors include contaminated water, food, poor sanitation, and international travel. Symptoms include abdominal pain, fever, diarrhea that may contain blood or mucus, and dehydration. Treatment involves antibiotics and rehydration. Prevention focuses on proper handwashing and drinking bottled water in areas with poor sanitation.