Funding for this research was provided by:
Centers for Disease Control and Prevention (U2GPS001421)
Received: 2 February 2018
Accepted: 17 September 2018
First Online: 26 October 2018
Ethics approval and consent to participate
: Ethical approval for this study was granted by the University of Zambia Biomedical Research Ethics Committee and the Institutional Review Board at the University of North Carolina at Chapel Hill, without requiring patient consent given the use of de-identified, routinely collected data.
: Not applicable.
: The authors declare that they have no competing interests.
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