HIV seroprevalence among street-recruited injection drug and crack cocaine users in 16 US municipalities

Objectives. This study determined human immunodeficiency virus (HIV) seroprevalence and factors associated with HIV infection among street-recruited injection drug users and crack cocaine smokers. Methods. An analysis was performed on HIV serologies and risk behaviors of 6402 injection drug users and 3383 crack smokers in 16 US municipalities in 1992 and 1993. Results. HIV seroprevalence was 12.7% among injection drug users and 7.5% among crack smokers. Most high-seroprevalence municipalities (>25%) were located along the eastern seaboard of the United States. In high-seroprevalence municipalities, but not in others, HIV seroprevalence was higher for injection drug users than for crack smokers. Among injection drug users, cocaine injection, use of speedballs (cocaine or amphetamines with heroin), and sexual risk behaviors were independently associated with HIV infection. Among crack smokers, sexual risk behaviors were associated with HIV infection. Conclusions. Injection drug users and crack smokers are at high risk for HIV infection.