HIV infection in the Women's Jail, Orange County, California, 1985 through 1991.

The incidence and prevalence of human immunodeficiency virus (HIV) infection among injection drug users, prostitutes, and other women seeking confidential testing in the Orange County Women's Jail were assessed from 1985 to 1991. A total of 4616 voluntary tests were completed on 3051 women, and 865 women were tested repeatedly. Eighty-two women tested positively, a ratio of 1.8 positives per 100 tests or 2.7% of all persons tested. Cumulative HIV prevalence increased from 2.5% to 2.7% between 1985 and 1991, increased by age, and showed racial differences. Of women with multiple tests, 29 seroconverted. Incidence declined from 5.7 to 1.4 cases per 100 person-years of observation between 1985 and 1991. The overall rate of seroconversion was 1.6 per 100 person-years of observation.