[1] Mahidol Univ, Fac Trop Med, MORU, Bangkok 10400, Thailand
[2] Univ Oxford, Nuffield Dept Clin Med, Oxford Ctr Trop Med & Global Hlth, Oxford, England
[3] Univ Amsterdam, Acad Med Ctr, Dept Intens Care, Amsterdam, Netherlands
[4] Univ Oxford, Clin Res Unit, Hosp Trop Dis, Ho Chi Minh City, Vietnam
[5] Johannesburg Hosp, Dept Crit Care, Johannesburg, South Africa
[6] Univ Witwatersrand, Johannesburg, South Africa