The first of a series of papers concerning the evaluation of the dynamics of the AIDS epidemic in Brazil employing techniques of geographical analysis, is here presented. Results of research undertaken in the US (especially in New York City) are compared with those of a recent investigation carried out in the city of S.Paulo, Brazil (Grangeiro, 1994). In both, geographical patterns of socio-demographic variables correlate with different patterns of the spread of the AIDS epidemic through the transmission groups. Recent trends of the AIDS epidemic in Brazil: the displacement toward medium sized cities and expansion frontiers, increasing report of AIDS cases among the poor and underprivileged, changes in the pattern of transmission with proportional augmentation of heterosexual transmission and IDUs as transmission groups, are described and analised. The geographical distribution of the AIDS cases registered between 1987-1993 in Brazil throughout the Brazilian States is evaluated by means of worksheets, maps, and non-parametric statistics. Results show that Gravimetric Centers (obtained by the use of the calculus spatial means) of AIDS in Brazil are situated within a triangle the sides of which are formed lines joining the three main metropolitan areas of the wealthiest region of Brazil - the southeast, i.e. São Paulo, Rio de Janeiro and Belo Horizonte. These especially S. Paulo, function as points of attraction for these Gravimetric Centers (GCs) towards the south as compared with the GCs of the general population calculated ia accordance with data from the 1980 and 1991 censuses. It is possible to observe a displacement of the GCs toward the northwest over this period in accordance with the migration patterns of the Brazilian population in general, though with a dynamic of its own. These changes in the geographical, socio-demographic and transmission group patterns show the complex nature of the epidemic in Brazil and pose additional difficulties for the development of prevention strategies.
Acquired immunodeficiency; Residence characteristics; Socioeconomic factors