Funding for this research was provided by:
Grand Challenges Canada (KCU-0087-042)
Received: 13 June 2017
Accepted: 24 January 2018
First Online: 8 February 2018
Ethics approval and consent to participate
: Participants provided written consent before enrolment and ethics approval was provided by the Medical Research Council of Zimbabwe (MRCZ) and the London School of Hygiene & Tropical Medicine.
: Not applicable
: The authors declare that they do not have any competing interests.
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