1 Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan; Ministry of Health and Welfare and National Taiwan University Infectious Diseases Research and Education Center, Taipei, Taiwan.
2 Institute of Epidemiology and Preventive Medicine, College of Public Health, National Taiwan University, Taipei, Taiwan; Ministry of Health and Welfare and National Taiwan University Infectious Diseases Research and Education Center, Taipei, Taiwan; Advisory Committee, Taiwan Central Epidemic Command Center for Severe Special Infectious Pneumonia (COVID-19), Taipei, Taiwan; Division of Infectious Diseases, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan. Electronic address: fangct@ntu.edu.tw.