Funding for this research was provided by:
National Institute of Allergy and Infectious Diseases (R01AI095041)
Received: 3 June 2017
Accepted: 3 April 2018
First Online: 16 April 2018
Ethics approval and consent to participate
: Institutional Review Boards of the Johns Hopkins School of Medicine and the University of Witwatersrand in South Africa approved this study. All participants provided written consent to participate in the study.
: All co-authors provide their consent for publication.
: The authors declare that they have no competing interests.
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