Affiliations

• ¹ Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK kahung.chan@ndph.ox.ac.uk plho@hku.hk.
• ² Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
• ³ JC School of Public Health and Primary Care, Chinese University of Hong Kong, Hong Kong SAR, China kahung.chan@ndph.ox.ac.uk plho@hku.hk.
• ⁴ Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK.
• ⁵ Carol Yu Centre for Infection and Department of Microbiology, University of Hong Kong, Hong Kong SAR, China kahung.chan@ndph.ox.ac.uk plho@hku.hk.