Bioepidemiologia de possíveis vetores e riquétsias na microrregião de Juiz de Fora, médio Paraibuna, Minas Gerais, Brasil

Abstract

Rickettsial diseases caused by genus Rickettsia are zoonosis present in all continents. With exception of Rickettsia felis and Rickettsia akari, respectively associated to fleas and mites, the vectors and / or reservoirs of Rickettsia sp. are ticks. In Brazil, Amblyomma cajennense, Amblyomma aureolatum and Amblyomma ovale are the most important vectors to humans. This study aims evaluate the cycles of Rickettsia sp. in different regions of Juiz de Fora, Minas Gerais, Brasil, endemic area of Spotted Fever. Were collected and identified 5.832 specimens of potential vectors in the urban area, primarily in foci. The detection of Rickettsia sp. in the samples was analyzed by quantitative PCR using primers for amplification of ompA gene, and by qualitative PCR, used for detecting fragments of ompA, gltA and htrA. 12 samples of Amblyomma cajennense, species most observed in this study, and one of Rhipicephalus microplus, collected on horses, were positive in the quantitative PCR. A. cajennense, collected on equine, was positive for spotted fever group in the qualitative PCR. The temporal and spatial relationship of A. cjennense and horses indicate the involvement of these species in the enzootic cycle during the major activity of Rickettsia sp. in the foci. The anthropophily, potential of transmission and occurrence in foci, point to the role of this species as a vector in anthropophilic cycle. Inherent characteristics of the municipality can potentiate the circulation of rickettsiae in urban area, increasing the contact of hosts with tick , expanding the spread of this vector. The results indicate the need of implementation of the environmental surveillance to spotted fever in Juiz de Fora, especially by the monitoring of A. cajennense and horses.