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Article History

Received: 29 August 2017

Accepted: 20 June 2018

First Online: 13 July 2018

Ethics approval and consent to participate

: We obtained approval for the study from the Witwatersrand Human Research Ethics Committee, University of Witwatersrand (Approval Number: M130711) and the research committee of the Centers for Disease Control and Prevention (protocol number 6546). The study was registered on ExternalRef removed (NCT02352961). Voluntary written informed consent was obtained from all participants, and, in the case of illiterate participants, a thumbprint to acknowledge understanding in the presence of a witness was obtained.

: Not applicable.

: The authors declare that they have no competing interests.The funder of the study participated in the study design, data interpretation, and writing of the report. The corresponding author had full access to all the data in the study and had final responsibility for the decision to submit for publication.

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