The epidemiology of HIV and AIDS in the United States.

The HIV/AIDS epidemic has slowed in growth and is approaching a leveling in incidence. However, the number of HIV-infected persons is high, and new infections continue to occur. The prevention of AIDS-related OIs and decreases in AIDS-related mortality are an encouraging sign that HIV-infected persons are living better and longer lives. However, if the improvements in clinical management and patient survival are not matched by reductions in HIV incidence, the population of HIV-infected persons will increase. The characteristics of persons with HIV infection are changing over time and must be monitored to properly target prevention and care. HIV/AIDS rates are highest for black and Hispanic Americans, and one fifth of persons with AIDS are women. Because of the decreases in HIV incidence and in prevalence for homosexual and bisexual men, an increasing proportion of infections in the United States are related to injecting drug use and heterosexual transmission. The characteristics of persons at risk for HIV infection differ regionally, and prevention efforts must be based on the characteristics of local HIV/AIDS trends. The reduction in the number of children with AIDS and HIV-infected transfusion recipients reflects the impact of an effective prevention intervention. The changes for homosexual and bisexual men and IDUs suggest a reduction in high-risk behaviors since the early years of the epidemic. Behavioral surveys indicate that heterosexual persons in the general population have adopted some protective behaviors, which may explain in part the HIV/AIDS surveillance trends. However, many young homosexual and bisexual men, IDUs, and other heterosexual persons continue to practice behaviors that lead to HIV infection. Further reduction in these risk behaviors and the adoption of protective behaviors among these populations will be necessary to further slow the spread of HIV infection and decrease the number of infected persons.