Common causes of acute gastroenteritis are viral infections, bacterial infections, parasitic infections and non-infectious factors such as poor diet. 1. viral infection, for adults and cold season. Most acute gastroenteritis in infants and children is caused by viral infections. Common viruses include rotavirus, norovirus, adenovirus, etc. Rotavirus mainly infects infants and young children, and norovirus mainly infects children and adults. 2. Bacterial infection, eating food or raw water contaminated by bacteria can cause acute gastroenteritis. Commonly infected bacteria in children include Escherichia coli and Campylobacter. Adults are often infected with Salmonella, dysentery bacillus and so on. 3. Parasite infection, often caused by infected parasites such as amoeba. 4. Non-infectious factors, eat raw cold, too hot, a lot of acidic food, toxic food, gastrointestinal tract stimulating drugs such as aspirin, alcoholism, etc. can also cause acute gastroenteritis. The specific cause of the disease should need to be confirmed by a doctor based on medical history, laboratory results, etc., and standardized diagnosis and treatment under the guidance of the doctor.