[1] Acad Med Ctr, Dept Global Hlth, Amsterdam, Netherlands
[2] Amsterdam Inst Global Hlth & Dev, Pietersbergweg 17, NL-1105 BM Amsterdam, Netherlands
[3] Kenya Govt Med Res Ctr, Kisumu, Kenya
[4] Univ Amsterdam, Acad Med Ctr, Div Infect Dis, Dept Internal Med, Amsterdam, Netherlands
[5] Natl AIDS & STI Control Programme, Nairobi, Kenya
[6] US Ctr Dis Control & Prevent, Kisumu, Kenya