[1] Univ Cape Town, Inst Infect Dis & Mol Med, Cape Town, South Africa
[2] Univ Cape Town, Div Med Virol, Dept Pathol, Cape Town, South Africa
[3] Univ Witwatersrand, Wits Reprod Hlth & HIV Inst, Sch Clin Med, Fac Hlth Sci, Johannesburg, South Africa
[4] Natl Inst Communicable Dis, Natl Hlth Lab Serv, Johannesburg, South Africa
[5] Univ Witwatersrand, Sch Pathol, SA MRC Antibody Immun Res Unit, Fac Hlth Sci, Johannesburg, South Africa
[6] Ctr AIDS Programme Res South Africa, Durban, South Africa
[7] Africa Hlth Res Inst, Durban, South Africa
[8] Univ KwaZulu Natal, Sch Lab Med & Med Sci, Durban, South Africa
[9] Max Planck Inst Infect Biol, Berlin, Germany
[10] Univ Cape Town, Wellcome Ctr Infect Dis Res Africa, Cape Town, South Africa