[1] Nanyang Technol Univ, Sch Biol Sci, Singapore, Singapore
[2] Univ Amsterdam, Amsterdam UMC, Amsterdam Inst Global Hlth & Dev, Dept Global Hlth, Amsterdam, Netherlands
[3] Mahidol Univ, Fac Trop Med, Mahidol Oxford Trop Med Res Unit, Bangkok, Thailand
[4] Univ Oxford, Ctr Trop Med & Global Hlth, Nuffield Dept Med, Oxford, England
[5] Univ Amsterdam, Ctr Trop Med & Travel Med, Acad Med Ctr, Dept Infect Dis, Amsterdam, Netherlands
[6] Univ Oxford, Nuffield Dept Med, Oxford, England