Funding for this research was provided by:
Centers for Disease Control and Prevention (200-2012-53587/0006)
Received: 10 October 2017
Accepted: 30 May 2018
First Online: 15 June 2018
Ethics approval and consent to participate
: Participants read and signed an informed consent form and HIPAA authorization. All study procedures, including consent processes, were approved in advance by the Marshfield Clinic Institutional Review Board.
: The authors declare that they have no competing interests.
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