Dinâmica de transmissão do dengue na cidade de Uberlândia, MG: uma abordagem ecoepidemiológica

Abstract

The landscape is an important element in the transmission of several diseases, mainly of those transmitted by vectors. The form as man organizes himself in the space and interacts with the natural environment, can cause irreversible damages to this environment and, that negative interaction affects health. Since 1993, annually they happen epidemic irruptions of dengue, in Uberlândia, MG. Emergential and permanent actions of combat to the Aedes aegypti vector have been taken, as well as a population awareness work, regarding to the risks of the disease. Nevertheless, the disease has been increasing in a preoccupying. The present study aimed: to determine the coeffícients of incidence of the dengue in the urban area of the municipal district, according to sex, age group and place; to evaluate the distribution of dengue incidence in the population, related to time and space; to analyze the possible association of the infection indexes and of infestation, with selected environmental variables, including: altitude and drainage, infestation index, population density, domicile condensing, frequency of garbage collection, number of dump centrais and vague lots. The epidemic picture of the dengue was established by means of the incidence of the disease and of the infestation by Aedes aegypti, having as reference data of the year of 1999, obtained from the Secretaria Municipal de Saúde de Uberlândia (Uberlândia health offíce). The zoning of the study area was accomplished by means of a graphic analysis of the urban area neighborhoods distribution (mapping). The division of the city in sections corresponded to the new distribution of the integrated neighborhoods. Each section included ten space units (corresponding to neighborhoods and/or integrated neighborhoods). No-parametric statistical methods with levei of significance of 0.05 were applied. 2.424 cases of dengue were registered in the researched area, which corresponded to a general coefficient of incidence of 52,67 7 000hab. The incidence didn't present correlation with age groups (rs=0,6071, p=0,148), however it was different among the several age groups (Z=2,5766, p=0,01) and between the periods (dry and rainy) of the year (Z= ,6785, p=0,0074). In relation to the space, the incidence of the dengue was signifícantly different (X2=9,98, p=0,0408). The incidence didn't differ according to sex in the sections, but it varied for the feminine sex (X2 =9,57, p=0,0483). There was significant difference in the age groups from 0 to 09 years old (group less infected) among the sectors (X2= 11,84, p=0,0186) and the highest indexes happened at the sectors North and West and from 20 to 29 years old (group with the largest infection index and the largest discrepancy among the sectors), (X2=ll,46, p=0,0219). The incidence was also significant in the sectors West and North (X2=16,32, p=0,0120; (X2=12,92, p=0,0444, respectively). The incidence of the dengue was different among the sections in the months of: january, march and april (X2=10,87, p=0,0280; X2=12,13, p=0,0164; X2=ll,10, p=0,0254, respectively). The infestation by Aedes aegypti, was not statistically different among the sections: (Central, 0,80%, East, 1,25%, West, 1,16%, South, 1,81% and North, 0,99%). There was no correlation between infestation x infection (rs=0,0144, p=0,921). There was correlation between: the domicile condensed x infestation in the study area (rs = -0,3015, p=0.033), altitude x infection in the Central Section (rs=0,6758, p = 0,032), altitude x infection in the East sector (rs = -0,6636, p=0,036) and condensing of vague lots x infection in the West Sector (rs=0,6606, p=0,038). It is concluded that the epidemic situation of the dengue in Uberlândia, MG, is a concerning subject and ít’s very complex, presenting a multiplicity of factors which maintain the infection, and that, demands an urgent evaluation of dengue control strategies, adopted in the city, as well, an politics of the use and occupation of the soil that doesn't allow the real-estate speculation, fact that is contributing to the occurrence of vague lots and they serve as garbage deposits, forming potential breeding sites for vectors in those spaces.