Funding for this research was provided by:
Doris Duke Charitable Foundation
Received: 16 February 2018
Accepted: 10 October 2018
First Online: 19 October 2018
Ethics approval and consent to participate
: The University of Zambia Bioethics committee (UNZABREC) approved the study. All participants were asked to sign a consent form after they agreed to participate.
: Participants were informed that information may be published but confidentiality will be maintained.
: All authors declare no conflict of interest. All authors have read and approved the manuscript.
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