Funding for this research was provided by:
National Institute of Allergy and Infectious Diseases (1R01AI114310)
Center for AIDS Research, University of North Carolina at Chapel Hill (P30 AI50410, 5P30AI050410)
National Basic Research Program of China (973 Program) (2017YFE0103800)
Applied Basic Research Key Project of Yunnan (QD2017N030,C1034448)
University of North Carolina(UNC)–South China STD Research Training Centre (1D43TW009532)
National Center for Advancing Translational Sciences at the National Institutes of Health (UL1TR001111)
Received: 18 June 2018
Accepted: 4 October 2018
First Online: 16 October 2018
Ethics approval and consent to participate
: Ethics review committees in China(Guangdong provincial center for Skin diseases and STI Control)and the United States(the University of North Carolina at Chapel Hill and the University of California, San Francisco) provided study approval, and participants completed an online informed consent process.
: Not applicable
: The authors declare that they have no competing interests.
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