Seroprevalence of HIV in Africa: Winter 1990.

A compilation of hundreds of nonrandomized studies provides an overview of current patterns of human immunodeficiency virus (HIV) in Africa and the likely future epidemiology of acquired immunodeficiency syndrome (AIDS). The African situation is complicated by the presence of 2 viruses--HIV 1 and 2--each with different natural histories epidemiologies and prognoses. HIV-1 is most prevalent in East and Central Africa while HIV-2 is predominantly found in West Africa. HIV- 1 affects young people more than HIV-2. Initially both viruses affect more women than men but men over 50 years of age are disproportionately infected. Prostitutes comprise the major high-risk group with over 50% of urban prostitutes in Uganda Rwanda Malawi and Kenya infected. When the sex ratio in urban areas in near unity there is less of a reliance on prostitutes and a correspondingly lower rate of HIV infection. Although military personnel comprise a very small proportion of the population in Africa they are a major source of transmission throughout Africa as a result of their mobility. Puzzling is the finding that rural high-risk groups have higher HIV seroprevalence rates than low-risk group in both urban and rural areas. There are at least 3 major areas of HIV concentration that cross national borders: the Kagera Triangle the French-speaking West African Coast and the Congo River Basin. Infection is shifting from a few well-defined pockets to many more towns and villages and the full effect of AIDS has not yet been experienced in countries with high seroprevalence levels. Encouraging however is an apparent trend of decline in HIV seroprevalence among blood donors.