A study of the Alabama state AIDS database was conducted to determine whether differences exist in demographic and risk characteristics between patients with HIV-1 in Jefferson and Mobile County. The authors found that the age distribution of patients with HIV-1, the percent of those having AIDS, and the percent of those surviving were very similar. However, significant differences existed in patient-reported risk factors in the two counties. Homosexuality was reported as the major risk factor in both counties. However, there was proportionately more homosexuality reported in Jefferson County and, conversely, more heterosexuality reported in Mobile. There also were significant differences in race and gender distributions in the two counties. This was due in part to the proportionately higher prevalence of African American females of reproductive age with HIV-1 in Mobile County. This may pose a significantly greater risk for pediatric AIDS among African American females in Mobile County.