Mean AIDS incidence rates were calculated for three time periods, 1987-89, 1990-92, and 1993-96, using reported adult AIDS cases by county. The analysis included the following variables: "population of counties for resident AIDS cases"; "proportion of population residing in urban areas", and "concentration of poverty", stratifying by gender and exposure categories. The Southeast region has experienced the lowest increase, contrasting with the steep rise observed in the North and South between the second and third study periods. Comparing variations in incidence rates from 1990-92 and 1993-96 by region or population, the greatest increase was among women. In the larger cities, AIDS cases among "homo/bisexual men" predominate, although the proportion of cases among men who have sex with men has decreased as heterosexual cases have undergone a continuous increase. IDUs have been the core stratum in medium-sized counties. For the smallest counties, heterosexual transmission has been the basic element in local dynamics. Even though AIDS is still an urban phenomenon in Brazil, the epidemic is spreading to rural counties. Until recently it has mainly affecting relatively more affluent areas, but there is now an evident spread of the epidemic to poorer areas.
Acquired Immunodeficiency Syndrome; Spatial Analysis; Ecological Studies; Epidemiology
