1. Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT, USA
2. Department of Epidemiology and Public Health, Yale University School of Medicine, New Haven, CT, USA; Yale University Center for Interdisciplinary Research on AIDS (CIRA), New Haven, CT, USA
3. New Haven Health Department STD Clinic, New Haven, CT, USA
4. Connecticut Department of Public Health, STD Control Program, Hartford, CT, USA