University of Cape Town (UCT) - Desmond Tutu HIV Centre, University of Cape Town (UCT) - Desmond Tutu HIV Centre, Queen Mary University of London - Wolfson Institute of Population Health, University of Cape Town (UCT) - Desmond Tutu HIV Centre, Queen Mary University of London - Blizard Institute, University of Cape Town (UCT) - Wellcome Centre for Infectious Diseases Research in Africa, Red Cross War Memorial Children’s Hospital - Paediatric Infectious Diseases Unit, University of East Anglia (UEA) - Norwich Medical School, University of East Anglia (UEA) - Faculty of Medicine and Health, Queen Mary University of London - Wolfson Institute of Population Health, University of Delhi - Institute of Eminence, London School of Hygiene & Tropical Medicine, Queen Mary University of London - Wolfson Institute of Population Health, University of Cape Town (UCT) - Wellcome Centre for Infectious Disease Research in Africa, Institute of Infectious Disease and Molecular Medicine, University of Cape Town (UCT) - Desmond Tutu HIV Centre and Queen Mary University of London - Barts and The London School of Medicine and Dentistry

London School of Hygiene & Tropical Medicine - Department of Clinical Research, Biomedical Research and Training Institute, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, University Teaching Hospital, Lusaka, London School of Hygiene & Tropical Medicine, London School of Hygiene & Tropical Medicine - Department of Clinical Research, University Teaching Hospital, Lusaka, Biomedical Research and Training Institute, Department of Paediatrics, University of Zimbabwe, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, University of Oxford - Nuffield Department of Medicine, affiliation not provided to SSRN, London School of Hygiene & Tropical Medicine - MRC Tropical Epidemiology Group (TEG), University of East Anglia (UEA) - Norwich Medical School, University Teaching Hospital, Lusaka and University of Bristol - Musculoskeletal Research Unit

Clinical Research Department, London School of Hygiene and Tropical Medicine, London School of Hygiene & Tropical Medicine, Biomedical Research and Training Institute, Biomedical Research and Training Institute, MRC International Statistics and Epidemiology Group, London School of Hygiene and Tropical Medicine, Biomedical Research and Training Institute, London School of Hygiene & Tropical Medicine, Biomedical Research and Training Institute, London School of Hygiene & Tropical Medicine - MRC Tropical Epidemiology Group (TEG), Department of Paediatrics, University of Zimbabwe, University of Southampton - Medical Research Council Life Course Epidemiology Unit, London School of Hygiene & Tropical Medicine - Department of Clinical Research and University of Bristol