Funding for this research was provided by:
United States Agency for International Development (72067419CA00004, AID-674-A-12-00029)
Text and Data Mining valid from 2019-10-25
Received: 1 September 2018
Accepted: 15 October 2019
First Online: 25 October 2019
Ethics approval and consent to participate
: The protocol was approved by the Human Research Ethics Committee (No. M140104) at the University of the Witwatersrand.
: Not applicable.
: The authors declare that they have no competing interests.