Funding for this research was provided by:
World Health Organization
Article History
Received: 13 February 2017
Accepted: 5 March 2018
First Online: 10 April 2018
Ethics approval and consent to participate
: Ethical approval was granted by the University of the Witwatersrand, Human Subjects Research Committee M981001, and by the Scientific and Ethical Review Group of the World Health Organization (SERG). All participants completed a written informed consent prior to any study procedures.
: N/A
: The authors declare that they have no competing interests (MB IK JS).
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