COVID-19(24) Patient(9) coronavirus(8) coronavirus disease(8) Mortality(8) Mild(7) Myocardial infarction(7) stroke(7) SARS-CoV-2(7) herpes zoster(7) Hepatitis B, chronic(6) acute respiratory syndrome(6) 95% CI(6) 95% confidence interval(6) acute respiratory syndrome coronavirus(5) Coronavirus disease 2019(5) Infection(5) age(5) retrospective cohort study(5) comparable(5) Hepatitis B virus(5) patients(5) Pneumonia(5) severe acute respiratory syndrome coronavirus 2(4) median(4) viral clearance(4) disease outbreaks(4) enzyme-linked immunosorbent assay(4) single center(4) antibody formation(4)