[1] Yale Univ, Sch Med, Dept Epidemiol & Publ Hlth, New Haven, CT 06510 USA
[2] Yale Univ, Ctr Interdisciplinary Res AIDS, CIRA, New Haven, CT USA
[3] New Haven Hlth Dept, STD Clin, New Haven, CT USA
[4] Connecticut Dept Publ Hlth, STD Control Program, Hartford, CT USA