About the Authors
UK Department for International Development (DFID) - Southern Africa, Pretoria, South Africa
Faculty of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, United Kingdom
RF is an adviser for DFID. The authors have declared that no other competing interests exist.
Analyzed the data: NK AH RF. Wrote the first draft of the manuscript: NK. Contributed to the writing of the manuscript: NK AH RF. ICMJE criteria for authorship read and met: NK AH RF. Agree with manuscript results and conclusions: NK AH RF.