The diagnosis of novel coronavirus pneumonia requires a combination of epidemiological history, clinical manifestations, and laboratory tests. (a) Epidemiological history: 1. history of travel or residence in the infected area or other areas with persistent local transmission within 14 days prior to the onset of the disease. 2. exposure to patients with fever or respiratory symptoms from the infected area or other areas with persistent local transmission within 14 days prior to the onset of the disease. 3. epidemiological association with aggregated onset or novel coronavirus infection. (B) Clinical manifestations: 1. fever. 2. imaging features of coronavirus pneumonia. 3. normal or reduced total white blood cell count or reduced lymphocyte count in early onset. (c) Laboratory tests: 1. Real-time fluorescence RT-PCR of respiratory specimens or blood specimens positive for novel coronavirus nucleic acid. 2. Viral gene sequencing of respiratory specimens or blood specimens highly homologous with known novel coronaviruses. The diagnosis can be confirmed by meeting 1 of (a); any 2 of (b); or 1 of (c).