Affiliations

• ¹ Victorian Infectious Diseases Reference Laboratory, North Melbourne, VIC, Australia; National Centre for Epidemiology and Population Health, Australian National University, Canberra, Australia.
• ² WHO Collaborating Centre for Infectious Disease Epidemiology and Control, School of Public Health, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong Special Administrative Region, China. Electronic address: bcowling@hku.hk.