About the Authors
The London School of Hygiene and Tropical Medicine, London, United Kingdom
The Carter Center, Bahir Dar, Ethiopia
The Carter Center, Atlanta, Georgia, United States of America
Light For The World, Addis Ababa, Ethiopia
The authors have declared that no competing interests exist.
Conceived and designed the experiments: SNR AB MZ TG CEG PME MJB. Performed the experiments: SNR EH. Analyzed the data: SNR HAW MJB. Wrote the paper: SNR MJB PME MJB.