The global epidemiology of the HIV/AIDS pandemic and its projected demographic impact in Africa.

The global epidemiology of HIV/AIDS has evolved to the point that the pandemic now predominantly affects heterosexuals, especially in developing countries. This article summarizes the status of the HIV/AIDS pandemic as of the early 1990s; provides estimates and short-term projections of AIDS mortality in a hypothetical country of sub-Saharan Africa; projects the potential demographic impact of AIDS in a hypothetical sub-Saharan country; and describes the major problems associated with modelling the long-term demographic impact of this pandemic. Estimated AIDS cases and deaths up to 1992 were extrapolated from public health surveillance data and through use of the WHO model. Estimates of HIV seroprevalence were based on available HIV serological data. For developed countries, HIV estimates developed by national experts and/or national AIDS programmes were used, and for developing countries estimates by regional experts were used or were prepared by WHO. For the first half of the 1990s, projections of AIDS cases and deaths were derived from the WHO model; beyond the mid-1990s, the potential effects of AIDS on selected demographic indicators were derived from a demographic projection model developed by the World Bank. Although estimates and long-term projections cannot be made with great precision, the general dimensions of the HIV/AIDS pandemic have been more clearly delineated now at the start of its second decade. Epidemiological data indicate that in industrialized countries, where extensive spread of HIV began in the late 1970s or early 1980s, the majority of HIV infections occurred during the first half of the 1980s.(ABSTRACT TRUNCATED AT 250 WORDS)