The clinical history, nursing records, and laboratory findings were reviewed for all patients. Clinical characteristics, including demographic information, daily body temperature, blood pressure, heart rate, clinical symptoms, and history of exposure to epidemic centers, were collected. Total white blood cell (WBC) counts, lymphocyte counts, ratio of lymphocyte, neutrophil count, ratio of neutrophil, procalcitonin (PCT), C-reactive protein level (CRP), and erythrocyte sedimentation rate (ESR) were measured. All threshold values chosen for laboratory metrics were based on the normal ranges set by each individual hospital.