Funding for this research was provided by:
Foundation for the National Institutes of Health (D43-TW010345)
National Institutes of Health (D43-TW010543])
National Research Foundation (119078)
Received: 5 August 2019
Accepted: 28 December 2019
First Online: 13 January 2020
Change Date: 2 March 2020
Change Type: Correction
Change Details: After publication of the original article , we were notified that there is a mistake in the article note.
Ethics approval and consent to participate
: Ethics was approved by the University of Cape Town Human Research Ethics Committee (HREC), approval number 674/2017. Written informed consent was obtained from each participant.
: Not applicable.
: The authors declare that they have no competing interests.