Funding for this research was provided by:
National Institute of Allergy and Infectious Diseases (1R01AI114310)
Received: 5 December 2017
Accepted: 10 May 2018
First Online: 18 May 2018
Ethics approval and consent to participate
: The study was reviewed and approved by the Institutional Review Board (IRB) of the Guangdong Provincial Center for Skin Diseases and STI Control (Guangzhou, China) and the University of North Carolina at Chapel Hill (North Carolina, United States) (No: IGHID 11706) before launch. Participants were asked to sign an electronic informed consent form when starting the survey.
: The authors declare that they have no competing interests.
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