1. Division of Epidemiology and Biostatistics, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China
2. Mathematical Modelling of Infectious Diseases Unit, Institut Pasteur, Paris, France
3. Division of Public Health Laboratory Sciences, School of Public Health
4. Centre of Influenza Research
5. Division of Community Medicine and Public Health Practice, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong SAR, China