University of Liverpool, University of Liverpool - Department of Public Health, Policy and Systems, Malawi Epidemiology and Intervention Research Unit (MEIRU), University of Liverpool, Research Triangle Institute (RTI) International, University of Malawi - College of Medicine, Malawi Epidemiology and Intervention Research Unit (MEIRU), Liverpool School of Tropical Medicine, Liverpool School of Tropical Medicine, Liverpool School of Tropical Medicine, Liverpool School of Tropical Medicine, University of Liverpool - School of Tropical Medicine, Malawi-Liverpool-Wellcome Trust Clinical Research Programme, St George’s University London - Institute for Infection and Immunity, Liverpool School of Tropical Medicine - Department of Clinical Sciences, Liverpool School of Tropical Medicine, University of Liverpool and University of Liverpool