Gastroenteritis, also known as infectious diarrhea, is inflammation of the gastrointestinal tract -- the stomach and small intestine. Symptoms may include diarrhea, vomiting, and abdominal pain. Fever, lack of energy, and dehydration may also occur. This typically lasts less than two weeks. It is not related to influenza though it has been called the stomach flu. Gastroenteritis is usually caused by viruses. However, bacteria, parasites, and fungus can also cause gastroenteritis. In children, rotavirus is the most common cause of severe disease. In adults, norovirus and Campylobacter are common causes. Eating improperly prepared food, drinking contaminated water, or close contact with a person who is infected can spread the disease. Treatment is generally the same with or without a definitive diagnosis, so testing to confirm is usually not needed. Prevention includes hand washing with soap, drinking clean water, proper disposal of human waste, and breastfeeding babies instead of using formula. The rotavirus vaccine is recommended as prevention for children. Treatment involves getting enough fluids. For mild or moderate cases, this can typically be achieved by drinking oral rehydration solution. In those who are breast fed, continued breastfeeding is recommended. For more severe cases, intravenous fluids may be needed. Fluids may also be given by a nasogastric tube. Zinc supplementation is recommended in children. Antibiotics are generally not needed. However, antibiotics are recommended for young children with a fever and bloody diarrhea.