1 South African Medical Research Council, 7505 Cape Town, South Africa; Department of Paediatrics and Child Health, University of Pretoria, Pretoria, South Africa. Electronic address: ameena.goga@mrc.ac.za.
2 Desmond Tutu HIV Centre, Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa.
3 Pathogenesis and Control of Chronic Infections, INSERM, Etablissement Français du Sang, University of Montpellier, CHU Montpellier, Montpellier, France.
4 ICAP, Columbia University, New York, NY, USA.
5 Setshaba Research Centre, Soshanguve, Pretoria, South Africa.
6 South African Medical Research Council, 7505 Cape Town, South Africa.