Funding for this research was provided by:
National Institutes of Health (1U54HG006938)
South African Medical Research Council
National Research Foundation of South Africa
UK MRC/DfID African Research Leader Award
DST-NRF Centre of Excellence in Human Development
National Health Laboratory Service Research Trust
Received: 10 October 2017
Accepted: 11 April 2018
First Online: 19 April 2018
Ethics approval and consent to participate
: The study was approved by the University of Witwatersrand Human Research Ethics Committee. Written, informed consent was obtained from all study participants after full explanation of the study objectives and testing procedures.
: The authors declare they have no competing interests.
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