[1] Queen Mary Hosp, Infect Control Team, Hong Kong West Cluster, Hong Kong, Peoples R China
[2] Univ Hong Kong, Li Ka Shing Fac Med, Sch Nursing, Hong Kong, Peoples R China
[3] Queen Mary Hosp, Dept Microbiol, Hong Kong, Peoples R China
[4] Ctr Hlth Protect, Dept Hlth, Hong Kong, Peoples R China
[5] Univ Hong Kong, Carol Yu Ctr Infect, Hong Kong, Peoples R China