Funding for this research was provided by:
National Institute of Allergy and Infectious Diseases (R01AI119037)
National Institute on Drug Abuse (T32DA013911)
Received: 1 December 2017
Accepted: 19 September 2018
First Online: 29 September 2018
Ethics approval and consent to participate
: The protocol for this project is approved by four institutions’ research ethics committees /institutional review boards: South African Medical Research Council Human Research Ethics Committee, University of Cape Town Human Research Ethics Committee, Stellenbosch University Human Research Ethics Committee, and Boston University Institutional Review Board. Written, informed consent to participate in the study will be obtained from all participants if ≥18 years of age or written individual consent and separate parental consent if < 18 years.
: Not applicable.
: The authors declare that they have no competing interests.
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