[1] Univ Pittsburgh, Grad Sch Publ Hlth, Dept Epidemiol, 130 DeSoto St,503 Parran Hall, Pittsburgh, PA 15261 USA
[2] Univ Pittsburgh, Grad Sch Publ Hlth, Dept Infect Dis & Microbiol, Pittsburgh, PA 15260 USA
[3] Johns Hopkins Bloomberg Sch Publ Hlth, Dept Epidemiol, Baltimore, MD USA
[4] Johns Hopkins Bloomberg Sch Publ Hlth, Dept Int Hlth, Baltimore, MD USA
[5] Stellenbosch Univ, Dept Med, Fac Med & Hlth Sci, Cape Town, South Africa
[6] Stellenbosch Univ, Ctr Infect Dis, Cape Town, South Africa
[7] Univ Maryland, Sch Med, Inst Human Virol, Baltimore, MD 21201 USA
[8] Inst Human Virol, Int Res Ctr Excellence, Abuja, Nigeria
[9] Univ Cape Coast, Sch Med Sci, Dept Paediat, Cape Coast, Ghana
[10] Elizabeth Glaser Pediat AIDS Fdn, Washington, DC USA
[11] Univ Fed Rio De Janeiro, Projeto Praca Onze, Rio De Janeiro, Brazil
[12] Univ Pittsburgh, Sch Med, Div Infect Dis, Pittsburgh, PA USA