PIP: This report on AIDS in Africa is introduced with a discussion of the 1991 estimates of the prevalence of the disease worldwide and the special problems which Africa will have in fending off AIDS because of existing difficulties in improving the health status of its people. Data on surveillance of AIDS in Africa are presented, and the variations seen in the reliability of the reporting are noted. Country-specific prevalence data are also provided. The results of seroprevalence studies are discussed for selected populations, with the limitations of seroprevalence data duly noted. The 1985 discovery of HIV-2 in West Africa and its subsequent appearance in other parts of the world is mentioned as is the impact and assessment of AIDS-associated mortality. Modes of transmission are covered, starting with sexual transmission and preceding to perinatal and parenteral transmission (through blood transfusion and through injections and scarification). The clinical features of HIV infection are described to present recent developments in clinical diagnosis in Africans. The preliminary studies available on HIV infection in children in developing countries are also summarized. Ways to diagnose HIV infections in situations where diagnostic facilities are limited are covered. After a discussion of laboratory diagnosis procedures, the impact of AIDS in Africa is considered, and the devastating economic impact for families and society is described. Finally, the prospects for control of HIV infections are considered in terms of the World Health Organization's objectives of preventing new infections, supporting those already infected, and linking national and international efforts against AIDS. It is concluded that control of HIV through education, changes in sex behavior, use of condoms, control of sexually transmitted diseases, and screening of the blood supply is possible, but that no single nation in Africa has the resources necessary to control AIDS. How well the international community meets this challenge will have a profound impact on the future.