Funding for this research was provided by:
U.S. Department of Defense
Received: 10 April 2017
Accepted: 19 June 2017
First Online: 5 July 2017
: The opinions and statements contained within this article are the ones of the authors and are not to be construed as official or reflecting the views of AFRIMS, the US Army or Department of Defence.
: The study protocols were approved by the Institutional Review Board of Walter Reed Army Institute of Research (WRAIR IRB) as human subject research in compliance with the Helsinki Declaration guidelines. Written informed consent was obtained from each potential subject prior to participation in the study.
: Not applicable. No individual data is presented. All results include aggregate data.
: The authors declare that they have no competing interests.
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