The HIV epidemic: medical and social challenges.

The sudden appearance, rapid spread, and devastating clinical impact of HIV infection in Africa, Europe and North America has created a medical problem unprecedented in the modern era. HIV is sexually transmitted, afflicts sexual and racial minorities in developed countries, and appears likely to be fatal and incurable in a majority of infected people. Its epidemiology (transmission and natural history) and clinical manifestations have been well described, but treatment of HIV remains minimally effective, creating only a short respite from progressive deterioration. In the absence of effective vaccination, HIV will continue to spread, abetted by a long period of asymptomatic carriage during which carriers are infectious. It has spread internationally to most undeveloped countries aided by fear and ignorance. The problem will resist simple technological solutions and adversely impact the lives of tens of millions of people in these areas over the next several decades. In developed countries HIV will strain medical resources and kill several million people before the end of the century. Despite the tremendous problems created by the AIDS epidemic, it has driven a remarkable expansion of virologic and immunologic understanding which promises to ultimately lead to control of not only AIDS, but a variety of other serious diseases. The following reviews of pivotal issues in AIDS research document this progress.