1 State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China; Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China.
2 The Department of Health, Centre for Health Protection, Hong Kong Special Administrative Region, China.
3 State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China.
4 Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China.
5 State Key Laboratory for Emerging Infectious Diseases, Carol Yu Centre for Infection, Department of Microbiology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China; Department of Microbiology, Queen Mary Hospital, Hong Kong Special Administrative Region, China. Electronic address: kelvinto@hku.hk.