Suspected cases of novel coronavirus include the following: 1. a history of travel or residence in an infected area 14 days before onset; 2. having been exposed to patients with fever or respiratory symptoms from an infected area within 14 days before onset; 3. having a clustered illness or epidemiologically related to a person with novel coronavirus infection. Patients who meet the above criteria with febrile symptoms and imaging features of pneumonia, as well as normal or reduced total white blood cell count or reduced lymphocyte count early in the onset of the disease, are considered suspected cases of novel coronavirus.