Cai (2020)
COVID-19 in a designated infectious diseases hospital outside Hubei Province, China.
Laboratory Findings
Lymphocyte (1 unit increase vs. Not applicable)
Virus clearance
Hazard ratio: 1.950 (1.270-2.980) Adjusted model


Retrospective cohort study

Medical records


All the hospitalized COVID-19 patients in the only referral hospital in Shenzhen City, China, from January 11, 2020, to February 6, 2020 were enrolled in this retrospective cohort study.

The median age of all patients was 47 years (IQR, 33?61). 50% of all patients were male. The median body mass index (BMI) was 23.05 (20.92?25.44). 69.1% patients were imported cases from Wuhan City, the other 12.4% were from other areas of Hubei Province, 4.4% had not been to Hubei Province but were infected by people from Hubei Province, and the remaining 14.1% had no clear contact history. The most common symptom at onset of illness was fever (218 [73.15%] patients), but 10.1% had no symptoms at the onset. For the 30 people with no symptoms, 12 cases had early mild lesions, seven cases had advanced lesions, and only eleven cases had a normal CT. There were no remarkable values for eosinophils.


29 Day

Virus clearance


Pulmonary imaging showed that the lesions progressed more than 50% within 24-48 hours, indicating that the patients were severe. The CT manifestations of severe patients were diffuse lesions in both lungs, with uneven density, high ground glass density shadow, and consolidation, accompanied by fibrous streak shadow.

Laboratory Findings


Lymphocyte, 10^9/L

Not applicable

1 unit increase

Hazard ratio

1.950 (1.270-2.980)




Risk was adjusted for Age, Gender, BMI, Lymphocyte and Clinical classification (Nonsevere vs severe). The clearance of COVID-19 was defined as two consecutive negative results with qPCR detection at an interval of 24 hours.

Mortality may be lowered when cases are relatively mild, and there are sufficient medical resources to care and treat the disease. The crude numbers are very different.