Investigação da presença de Rickettsia em diferentes espécies de carrapatos infestando gambás (Didelphis albiventris) e capivaras (Hydrochoerus hydrochaeris) do Parque do Sabiá, Uberlândia, MG

Abstract

Located in Uberlândia, the Sabiá Park is the main public park of the city and habitat of several animal species, among them, Hydrochoerus hydrochaeris and Didelphis albiventris, which were collected between 2010 and 2013 ticks, which were stored in the Ixodology Laboratory - UFU. This study aimed to investigate the presence of bacteria of the genus Rickettsiae in these ticks. Three hundred and twenty one ticks of the species Amblyomma sculptum (adults and nymphs), Amblyomma dubitatum (nymphs), Ixodes loricatus (adults and nymphs) and cakes of larvae of Amblyomma sp. were used, combined in one hundred and eighty five DNA samples. A PCR of the extractions and electrophoresis in agarose gel was performed for visualization of molecular bands. Of these extractions, thirty one presented positive band for rRNA 16S. Of these, twelve samples showed amplification for a segment of the gtlA gene sequence of Rickettsia spp. and also specific amplification for gtlA of R. bellii, eight samples of A. dubitatum, one of A. sculptum, two of Amblyomma sp. larvae and one of I. loricatus. Three of these samples, one from A. dubitatum, one from A. sculptum collected from capybara and one from I. loricatus from opossum were sequenced and their nucleotide sequences were identical to each other. These sequences were also identical to the gltA sequences R. bellii from Colombia (MT174170, by Ixodes tropicalis), Argentina (MH282858, by Amblyomma ovale), USA (MN372317, by Rhipicephalus sanguineus), and several locations in Brazil (MK962697, by Amblyomma aureolatum, in the state of Espírito Santo; MN064678, state of Rio de Janeiro, by Amblyomma longirostre; MH236876, by Amblyomma rotundatum, in the state of Amapá; and others). Although the presence of Rickettsia from the macular fever group was not detected in this study and R. bellii presents undetermined pathogenicity in humans, the presence of A. sculptum and A. dubitatum in animals that live in the Sabiá Park reinforces the need to monitor the presence of Rickettsia spp. in ticks and their hosts, because the increase in the population of these animals may favor the development of vectors and possible cases of disease.