Funding for this research was provided by:
Wellcome Trust (WT083495MA)
Carnegie Corporation of New York
World Health Organization (TDR 184732)
Harry Crossley Foundation
Henry Trotter Foundation
Text and Data Mining valid from 2019-04-27
Received: 7 December 2017
Accepted: 8 April 2019
First Online: 27 April 2019
Ethics approval and consent to participate
: Ethical approval was obtained from the University of Southampton (Ref no: 12064) and the University of Cape Town Human Research Ethics Committee (HREC Ref no: 612/2014). Written informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.
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