The incubation period of novel coronavirus pneumonia is usually 3-7 days, with a maximum of 14 days, and the main manifestations are fever, malaise, and dry cough within 3-14 days of infection. It is usually accompanied by nasal congestion, runny nose and diarrhea. It is important to note that some patients with novel coronavirus pneumonia have mild symptoms and may not have significant fever. There are even a few infected patients who have no obvious clinical symptoms. Therefore, infection with novel coronavirus pneumonia may occur without fever or with symptoms of fever 3-14 days after infection.