Funding for this research was provided by:
Wellcome Trust
South African Medical Research Council
Centre of Excellence in Human Development, University of the Witwatersrand, Johannesburg, South Africa
Article History
Received: 21 February 2018
Accepted: 26 June 2018
First Online: 5 July 2018
Ethics approval and consent to participate
: Ethical clearance for this study and the Bt20+ study were obtained from the Human Research Ethics Committee of the University of the Witwatersrand, clearance numbers M160921 and M111182 respectively. All participants were provided with information on the study and its procedures and signed consent forms at enrolment.
: Not applicable.
: The authors declare that they have no competing interests.
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