1 The KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; The Childhood Acute Illness and Nutrition Network, Nairobi, Kenya.
2 The KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya; The Childhood Acute Illness and Nutrition Network, Nairobi, Kenya; The Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7LG, UK. Electronic address: [email protected].