COVID-19(8) 2019-nCoV(3) 2019 novel coronavirus(3) pneumonia.(2) Coronavirus disease 2019(2) novel coronavirus.(1) recurrence(1) Invasive pulmonary aspergillosis(1) Severity of illness.(1) delirium(1) SARS-CoV(1) Viral nucleic acid testing.(1) bronchoscopy(1) Radiography(1) infection.(1) Infection(1) 2019 novel coronavirus pneumonia(1) Epidemiology(1) Clinical characteristics(1) Pneumonia viral(1) mechanical ventilation(1) recurrence.(1) immune response(1) Bronchoalveolar lavage fluid(1) 2019 novel coronavirus infection(1) Infection prevention and control(1) antiviral therapy(1) Bronchoscope-guided(1) disease severity(1) Diagnosis and treatment(1)