London School of Hygiene & Tropical Medicine - Faculty of Infectious and Tropical Diseases, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, Ministry of Health and Child Care, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, Biomedical Research & Training Institute - The Health Research Unit Zimbabwe, University of Zimbabwe - Department of Community Medicine, Department of Paediatrics, University of Zimbabwe, London School of Hygiene & Tropical Medicine - MRC Tropical Epidemiology Group (TEG), London School of Hygiene & Tropical Medicine - Faculty of Infectious and Tropical Diseases, University of Bristol - Musculoskeletal Research Unit, University of Zimbabwe - Internal Medicine Unit, London School of Hygiene & Tropical Medicine - Department of Clinical Research, London School of Hygiene & Tropical Medicine - Faculty of Infectious and Tropical Diseases and London School of Hygiene & Tropical Medicine - Department of Clinical Research