Funding for this research was provided by:
Bill and Melinda Gates Foundation (OPP1136774)
Received: 26 October 2017
Accepted: 16 January 2018
First Online: 31 January 2018
Ethics approval and consent to participate
: Ethical approval has been obtained for this study from the London School of Hygiene and Tropical Medicine Observational Research Ethics Committee and the Medical Research Council of Zimbabwe. Participants will be asked for their informed consent to participate in all aspects of the study.
: Not Applicable.
: The authors declare that they have no competing interests.
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