[1] Univ Oxford, Nuffield Dept Populat Hlth, Old Rd Campus, Oxford, England
[2] Kenya Govt Med Res Ctr, Wellcome Trust Res Programme, Kilifi, Kenya
[3] Univ Washington, Dept Med, Seattle, WA 98195 USA
[4] Univ Washington, Dept Global Hlth & Epidemiol, Seattle, WA 98195 USA
[5] Univ Oxford, Nuffield Dept Med, Ctr Top Med & Global Hlth, Oxford, England
[6] Univ Amsterdam, Acad Med Ctr, Dept Global Hlth, Meibergdreef 9, NL-1105 AZ Amsterdam, Netherlands