“Diarrhea” is diarrhea, the pathogen commonly rotavirus, norovirus and enteric adenovirus, infectious. Viral infectious diarrhea, also known as viral gastroenteritis, is a group of acute intestinal infectious diseases, can be caused by a variety of viruses, to vomiting, diarrhea, watery stools as the main clinical features. 1. Rotavirus: it is an RNA virus, patients and asymptomatic carriers are the main source of infection, and some poultry and livestock with virus are also potential sources of infection. It is often transmitted through fecal-oral route and close family contact. Because of the low immunity of children, it is easier to be infected. 2. Norovirus: RNA virus, the source of infection is mainly patients, hidden infected and virus carriers, can be transmitted through fecal-oral, close contact and other ways, adults and older children. Common diarrhea manifestations, may be accompanied by abdominal pain, fever, headache, muscle pain and other symptoms. 3. Enteric adenovirus: it is a double-stranded linear DNA virus, patients and latent infections are the only source of infection, often through the digestive tract, contact and respiratory tract transmission, children under 5 years old are more common, adults are less common. Most are asymptomatic. Symptoms are predominantly diarrhea with low-grade fever and vomiting. In severe cases, dehydration and death may occur. Patients with diarrhea should go to regular hospitals for diagnosis of the pathogen and symptomatic treatment.