[1] Chinese Ctr Dis Control & Prevent, Natl Inst Communicable Dis Control & Prevent, State Key Lab Infect Dis Prevent & Control, Beijing 102206, Peoples R China
[2] First Peoples Hosp Yunnan Prov, Emergency Dept, Kunming 650034, Yunnan, Peoples R China
[3] Peoples Hosp Yuxi City, Intens Care Unit, Yuxi 653199, Yunnan, Peoples R China
[4] Chinese Ctr Dis Control & Prevent, Natl Inst Communicable Dis Control & Prevent, Changping Liuzi 5, Beijing 102206, Peoples R China