how long can viral gastroenteritis last in children
1 Rotavirus is the leading cause of gastroenteritis among children 3 to 15 months old. 2  Most children have been exposed to the virus by age 2. Children with rotavirus have vomiting and watery diarrhea for 3 to 8 days, along with fever and abdominal pain. Symptoms of rotavirus infection appear 1 to 2 days after exposure. 2  In the United States, rotavirus infections are most common from November to April. 3  Adenovirus serotypes 40 and 41 cause gastroenteritis mainly in children younger than 2 years old.