[1] Uganda Virus Res Inst, Rakai Project, Entebbe, Uganda
[2] Johns Hopkins Univ, Bloomberg Sch Publ Hlth, Dept Populat & Family Hlth Sci, Baltimore, MD USA
[3] Makerere Univ, Inst Publ Hlth, Kampala, Uganda
[4] Makerere Univ, Sch Med, Kampala, Uganda
[5] Columbia Univ, Joseph P Mailman Sch Publ Hlth, Heilbrun Ctr Populat & Family Hlth, New York, NY USA