Received: 3 October 2017
Accepted: 23 February 2018
First Online: 2 March 2018
Ethics approval and consent to participate
: The protocol was approved by the University of Cape Town Human Research Ethics Committee (HREC), the Health Research Committee of the Health Research and Knowledge Management Unit of KZN Department of Health, and the Comité de Protection de Personnes de Paris in France. All participants provided written informed consent. Participants under 18 years provided assent and their parents, guardians or caregivers provided written informed consent for them.
: Not applicable
: The authors declare that they have no competing interests.
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