Spatial dimensions of the spread of AIDS (Acquired Immune Deficiency Syndrome) have not attracted significant scientific attention. Most epidemiological studies of the spread of AIDS focus on male homosexuals and intravenous drug users. These studies imply that the spatial spread of AIDS will occur across geographical environments, but they have not been followed by systematic investigations of the geographic and temporal patterns of AIDS dispersal, or the types of geographical environments through which the spread of AIDS is most rapid. This project attempts to fill this gap in knowledge by investigating the spatial diffusion and forecasting of the AIDS epidemic. It will test hypotheses concerning the spatial diffusion of the epidemic in the aggregate and separately for the three major risk groups: male homosexuals and bisexuals, intravenous drug users, and heterosexuals. The hypotheses to be tested are drawn from the geographic literature on diffusion theory and spatial epidemiology and are set within conceptual understandings of the mechanisms and behaviors specific to the disease. At the core of the project, mathematical models will be developed relating incidences of AIDS to various temporal and spatial variables. The explanatory and predictive capabilities of these models will be tested at a number of different spatial scales, including counties. More focused tests will also be conducted for major risk groups in the 100 largest metropolitan areas, by counties within six states, and by census tracts for four major cities. Investigations of the spatial diffusion of AIDS are few, but they provide crucial inputs to knowledge about this critical problem. Further research on the spatial aspects of the spread of the epidemic is necessary to inform planners and policy makers as they formulate strategies to contain the epidemic. The spread of AIDS has an important spatial dimension, and this research will add significantly to the theoretical and empirical body of knowledge related to this important societal problem. This research will also enhance general understandings of the process of spatial diffusion.
