Triatomine geographical distribution, dispersion
rates and aspects of Trypanosoma cruzi natural infection associated with dwelling
characteristics and with socioeconomic and environmental conditions in the Cariri
region, state of Ceará.
Parasitology, Chagas disease, Triatominae, Spatial analysis, Entomological surveillance
Triatomines are responsible for the vector transmission of Chagas disease, which affects between 6 and 8 million people in continental Latin America, with an incidence of 28 thousand cases per year. In the state of Ceará, the predominance of Caatinga, besides a rural area with precarious human habitations, provides several types of shelters for these insects. In the present study, we evaluated the geographical distribution, the dispersion rates and the natural Trypanosoma cruzi infection in triatomines collected in the Cariri region, southern Ceará, and their association with dwelling, socioeconomic and environmental characteristics. The highest dispersion rates were registered in Antonina do Norte and Potengi. We found significative correlation between triatomine dispersion and income, work and environmental variables in the municipalities. The species T. pseudomaculata represented most of the specimens captured during the study period. In the domestic environment, most of the collected triatomines were identified as T. brasiliensis or T. pseudomaculata. The municipalities of Farias Brito and Potengi registered the highest triatomine rates for each 10 thousand inhabitants. The species P. megistus and R. nasutus presented the highest mean indexes for T. cruzi natural infection. In Farias Brito and Potengi, most of the dwellings where T. cruzi-positive triatomines were captured had external bathroom, perch, cats, dogs and hen houses. However, we did not find significative correlation between the characteristics of the domiciles and the
positivity for T. cruzi in triatomines. Our results reinforce the importance of the entomological surveillance for Chagas disease vectors in endemic areas in the Brazilian northeast.