Molecular Detection of Rickettsia spp. in Free Living Ticks in Military Instruction Areas in Southeast Brazil

Abstract The present study aimed for the molecular detection of Rickettsia spp. in ticks collected from military training areas in southeastern Brazil. Previously, a total of 9,374 free-living ticks in 66 military instruction areas of five Military Organizations (MOs) were collected. From these, a sample of 1,885 ticks was used for molecular analysis..DNA extraction was performed using the “HotSHOT” technique, and PCR was performed using the Rickettsia spp. gltA, 17kDa and ompA genes. It was found that 11 samples produced DNA sequences of sizes compatible with the Rickettsia spp. gltA and 17kDa gene and two of these, also for ompA, with a prevalence of 0.58% (11/1885). Analyses of amplified fragments of gltA identified the samples as Rickettsia bellii in seven nymphs of Amblyomma dubitatum and one nymph of Amblyomma sculptum, and identified samples as Rickettsia sp. in two nymphs of A. dubitatum and one of A. sculptum. This finding warns the possibility of the risk of exposure of military personnel to ticks infected with Rickettsia spp. during training.