[1] Ctr Hlth Protect, Dept Hlth, Publ Hlth Lab Serv Branch, Div Virol, Hong Kong, Hong Kong, Peoples R China
[2] Chinese Univ Hong Kong, Fac Med, Dept Microbiol, Shatin, Hong Kong, Peoples R China
[3] Chinese Univ Hong Kong, Fac Med, Stanley Ho Ctr Emerging Infect Dis, Shatin, Hong Kong, Peoples R China