[1] Jinan Municipal Ctr Dis Control & Prevent, Div Bacteria Dis, 2 Weiliu Rd, Jinan, Shandong, Peoples R China
[2] Chinese Ctr Dis Control & Prevent, State Key Lab Infect Dis Prevent & Control, 155 Changbai Rd, Beijing, Peoples R China
[3] Capital Inst Pediat, Dept Bacteriol, Beijing, Peoples R China