Funding for this research was provided by:
Bristol-Myers Squibb Foundation (430960)
Deutscher Akademischer Austauschdienst (Scholarship)
National Research Foundation (Scholarship)
Received: 25 November 2019
Accepted: 14 May 2020
First Online: 1 June 2020
Ethics approval and consent to participate
: This study was approved by the University of Cape Town, Faculty of Health Sciences Human Research Ethics committee (HREC Ref no: 520/2017) and permission to conduct the study was obtained from the provincial and local government health departments.
: Not applicable.
: The authors declare that they have no competing interests.