Bacterial gastroenteritis is a common infection. It can cause loose stools, throwing up, and belly problems. This illness is very contagious and the germs are easy to spread. Most children get better in a few days without treatment. With this health problem, your child may have trouble keeping down fluids. This puts your child at risk of losing too much fluid. This is also called dehydration. Preventing dehydration is the most important treatment goal. Your child may need drugs to treat the infection in very bad cases.