National Centre for Infectious Diseases, Singapore, National Public Health and Epidemiology Unit, National Centre for Infectious Diseases, Agency for Science, Technology and Research (A*STAR) - Singapore Immunology Network (SIgN), National Centre for Infectious Diseases, Singapore, Duke NUS Medical School, Agency for Science, Technology and Research (A*STAR) - Singapore Immunology Network (SIgN), Government of the Republic of Singapore - Communicable Diseases Division, Ministry of Health, Singapore, National Centre for Infectious Diseases, Singapore, Duke NUS Medical School, Agency for Science, Technology and Research (A*STAR) - Singapore Immunology Network (SIgN), National University of Singapore (NUS) - Department of Infectious Diseases, Ng Teng Fong General Hospital - Division of Infectious Diseases, National University Health System, Singapore; Yong Loo Lin School of Medicine, National University of Singapore, Khoo Teck Puat Hospital, Changi General Hospital - Department of Infectious Diseases, Alexandra Hospital, Duke-NUS Medical School, National Centre for Infectious Diseases, National University of Singapore (NUS) - Department of Microbiology and Immunology, Agency for Science, Technology and Research (A*STAR) - Infectious Diseases Horizontal Technology Centre, Duke NUS Medical School, Agency for Science, Technology and Research (A*STAR) - Singapore Immunology Network (SIgN), Agency for Science, Technology and Research (A*STAR) - Bioinformatics Institute, Nanyang Technological University (NTU) - Lee Kong Chian School of Medicine and Ministry of Health, Singapore