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Background: Coxiella burnetii, the etiologic agent of Q fever, is a highly infectious zoonotic bacterium. Genetic information about the strains of this worldwide distributed agent circulating on the African continent is limited. The aim of the present study was the genetic characterization of C. burnetii DNA samples detected in ticks collected from Ethiopian cattle and their comparison with other genotypes found previously in other parts of the world., Methodology/principal Findings: A total of 296 tick samples were screened by real-time PCR targeting the IS1111 region of C. burnetii genome and from the 32 positive samples, 8 cases with sufficient C. burnetii DNA load (Amblyomma cohaerens, n = 6; A. variegatum, n = 2) were characterized by multispacer sequence typing (MST) and multiple-locus variable-number tandem repeat analysis (MLVA). One novel sequence type (ST), the proposed ST52, was identified by MST. The MLVA-6 discriminated the proposed ST52 into two newly identified MLVA genotypes: type 24 or AH was detected in both Amblyomma species while type 26 or AI was found only in A. cohaerens., Conclusions/significance: Both the MST and MLVA genotypes of the present work are closely related to previously described genotypes found primarily in cattle samples from different parts of the globe. This finding is congruent with the source hosts of the analyzed Ethiopian ticks, as these were also collected from cattle. The present study provides genotype information of C. burnetii from this seldom studied East-African region as well as further evidence for the presumed host-specific adaptation of this agent.

The expanding family of Francisellaceae includes the genus Francisella, where several pathogen bacteria, e.g. the zoonotic F. tularensis, and different Francisella-like agents belong to. Francisella-like endosymbionts (FLEs) are widespread in hard and soft ticks and their pathogenicity is unknown. The examination of 296 ticks collected in Ethiopia was performed for the detection of F. tularensis and FLEs using polymerase chain reaction (PCR) assays based on the amplification of 16S rRNA, sdhA and tul4 gene fragments. FLE was described in one Hyalomma rufipes tick based on the 16S rRNA and sdhA gene sequences. The 16S rRNA gene fragment was identical with the ones detected previously in Rhipicephalus sanguineus and Hyalomma marginatum marginatum in Bulgaria. The presence of endosymbionts with identical 16S rRNA gene sequence in both Rhipicephalus and Hyalomma species further supports the hypotheses, that certain FLEs had independent evolution from their tick hosts., (Copyright © 2014 Elsevier GmbH. All rights reserved.)

Background: The majority of vector-borne infections occur in the tropics, including Africa, but molecular eco-epidemiological studies are seldom reported from these regions. In particular, most previously published data on ticks in Ethiopia focus on species distribution, and only a few molecular studies on the occurrence of tick-borne pathogens or on ecological factors influencing these. The present study was undertaken to evaluate, if ticks collected from cattle in different Ethiopian biotopes harbour (had access to) different pathogens., Methods: In South-Western Ethiopia 1032 hard ticks were removed from cattle grazing in three kinds of tick biotopes. DNA was individually extracted from one specimen of both sexes of each tick species per cattle. These samples were molecularly analysed for the presence of tick-borne pathogens., Results: Amblyomma variegatum was significantly more abundant on mid highland, than on moist highland. Rhipicephalus decoloratus was absent from savannah lowland, where virtually only A. cohaerens was found. In the ticks Coxiella burnetii had the highest prevalence on savannah lowland. PCR positivity to Theileria spp. did not appear to depend on the biotope, but some genotypes were unique to certain tick species. Significantly more A. variegatum specimens were rickettsia-positive, than those of other tick species. The presence of rickettsiae (R. africae) appeared to be associated with mid highland in case of A. variegatum and A. cohaerens. The low level of haemoplasma positivity seemed to be equally distributed among the tick species, but was restricted to one biotope type., Conclusions: The tick biotope, in which cattle are grazed, will influence not only the tick burden of these hosts, but also the spectrum of pathogens in their ticks. Thus, the presence of pathogens with alternative (non-tick-borne) transmission routes, with transstadial or with transovarial transmission by ticks appeared to be associated with the biotope type, with the tick species, or both, respectively.