Funding for this research was provided by:
Centers for Disease Control and Prevention (NU17CE002721)
Received: 15 January 2018
Accepted: 28 March 2018
First Online: 6 April 2018
Ethics approval and consent to participate
: All study protocols were reviewed and awarded exempt status by Indiana University’s Institutional Review Board (study protocol# 1801650513). Participation consent was not required due to the anonymous nature of the data.
: Not applicable.
: The authors declare that they have no competing interests.
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