Funding for this research was provided by:
Department for International Development, UK Government
National Institute of Allergy and Infectious Diseases (UM1AI068619)
National Institute of Mental Health (UM1AI068617)
National Institute on Drug Abuse (UM1AI068613)
Received: 9 September 2017
Accepted: 10 May 2018
First Online: 29 May 2018
Ethics approval and consent to participate
: Written informed consent was obtained from all participants prior to data collection and parental assent was collected for young women under 18 years. The study was approved by the London School of Hygiene and Tropical Medicine Research Ethics Committee (reference number 6306), the Human Research Ethics Committee (Medical) at the University of Witwatersrand Johannesburg (reference number 120804), the University of North Carolina, Chapel Hill Institutional Review Board (IRB) (no reference number), and the Department of Health and Education, Mpumalanga Province, South Africa (no reference number) where the research was conducted.
: The authors declare that they have no competing interests.
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