1. a Comprehensive Drug Research Center, University of Miami School of Medicine, Department of Medicine & Department of Epidemiology and Public Health , Miami, Florida
2. b AIDs Surveillance Program , Guangxi Health and Anti-Epidemic Center , Guangxi Province, China
3. c Department of Epidemiology , Johns Hopkins University School of Hygiene and Public Health , Baltimore, Maryland
4. d Department of Anthropology , University of Miami School of Medicine , Miami, Florida
5. e Department of Epidemiology and Public Health , University of Miami School of Medicine , Miami, Aorida
6. f Guangxi Health and Anti-Epidemic Center , Guangxi Province, China
7. g AIDs Surveillance Program , Guangxi Health and Anti-Epidemic Center , Guangxi Province, China
8. h Comprehensive Drug Research Center, University of Miami School of Medicine, Department of Epidemiology and Public Health , Miami, Florida
9. i Department of Molecular Microbiology and Immunology , Johns Hopkins University School of Hygiene and Public Health , Baltimore, Maryland