1 Department of Paediatrics and Child Health, School of Clinical Medicine, University of KwaZulu Natal, Durban, South Africa. Electronic address: masekelar@ukzn.ac.za.
2 Liverpool School of Tropical Medicine, Liverpool, UK.
3 The Nairobi Hospital, Nairobi, Kenya.
4 Department of Medicine, Faculty of Clinical Sciences, College of Medicine, University of Lagos, and The Lagos University Teaching Hospital, Lagos, Nigeria.