[1] Johns Hopkins Univ, Sch Med, Dept Psychiat & Behav Sci, AIDS Psychiat Serv, Baltimore, MD USA
[2] Johns Hopkins Univ, Sch Med, Div Gen Internal Med, Baltimore, MD USA
[3] Ctr Dis Control & Prevent, Natl Ctr Birth Defects & Dev Disabil, Prevent Res Branch, Atlanta, GA USA
[4] Druid STD Clin, Baltimore City Hlth Dept, Baltimore, MD USA
[5] Denver Publ Hlth, Denver, CO 80204 USA