Funding for this research was provided by:
Received: 24 January 2019
Accepted: 30 April 2019
First Online: 31 May 2019
Ethics approval and consent to participate
: The protocol received ethical approval from the Institutional Review Board of BRTI; Medical Research Council of Zimbabwe; Research Council of Zimbabwe and the Ethics Committee of the Liverpool School of Tropical Medicine. Consent was sought from the head of facilities and all HWs provided informed consent.
: Not applicable.
: The authors declare that they have no competing interests.
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