[1] Natl Inst Infect Dis, Dept Bacterial Pathogenesis & Infect Control, Musashimurayma, Tokyo 2080011, Japan
[2] Minist Hlth, World Hlth Org Representat Off, Phnom Penh, Cambodia
[3] Minist Hlth, Dept Natl Immunizat Program, Phnom Penh, Cambodia
[4] World Hlth Org Western Pacific Reg Off, Manila, Philippines