Detection of Rickettsia spp. in Fleas Collected from Small Mammals in Slovakia, Central Europe.

This survey is aimed at investigation of species composition of fleas removed from small terrestrial mammals captured in rural, suburban, and urban types of habitat and molecular screening of the presence and diversity of Rickettsia species in collected ectoparasites. In total, 279 fleas (Siphonaptera) belonging to 9 species of 2 families, Ceratophyllidae and Hystrichopsyllidae, were collected from 115 (46%) out of 250 trapped small mammals of eight species (Apodemus agrarius, Apodemus flavicollis, Apodemus uralensis, Myodes glareolus, Microtus arvalis, Microtus subterraneus, Crocidura leucodon, and Sorex minutus). Rickettsia spp. were found in 2.5% (7/279) of tested fleas, namely in Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus uncinatus, Megabothris turbidus, and Amalareus penicilliger. Rickettsia felis, Rickettsia helvetica, and unidentified Rickettsia species were detected in fleas infesting small mammals in Eastern Slovakia. The results of the study suggest that some species of rickettsiae have a different range of arthropod vectors.

Ticks, fleas and rodent-hosts analyzed for the presence of Borrelia miyamotoi in Slovakia: the first record of Borrelia miyamotoi in a Haemaphysalis inermis tick.

In Slovakia, little knowledge is available on the occurrence, hosts and vectors of Borrelia miyamotoi of the relapsing fever group. In the current study, 2160 questing and rodent-attached ticks of six species (Ixodes ricinus, Ixodes trianguliceps, Dermacentor marginatus, Dermacentor reticulatus, Haemaphysalis concinna and Haemaphysalis inermis), 279 fleas belonging to 9 species (Ctenophthalmus agyrtes, Ctenophthalmus solutus, Ctenophthalmus assimilis, Megabothris turbidus, Amalareus penicilliger, Hystrichopsylla orientalis, Ctenophthalmus uncinatus, Doratopsylla dasycnema and Nosopsyllus fasciatus) and skin biopsies from 245 small mammals belonging to eight species (Apodemus agrarius, Apodemus flavicollis, Apodemus uralensis, Myodes glareolus, Crocidura leucodon, Micromys minutus, Microtus arvalis, Microtus subterraneus) were screened for the presence of B. miyamotoi DNA. The overall prevalence of B. miyamotoi found in questing and rodent-attached ticks was 1.8% (23 positive/1260 examined) and 3.4% (31 positive/900 examined), respectively. Borrelia miyamotoi was detected in questing I. ricinus, rodent-attached I. ricinus and H. inermis ticks, and in one male of the common vole (M. arvalis) in different habitats (mainly rural) in eastern Slovakia. However, B. miyamotoi was not found in any of the tested fleas. Our findings indicate that rural habitats with different species of tick vectors and hosts are appropriate for the occurrence of B. miyamotoi.

Molecular evidence and diversity of the spotted-fever group Rickettsia spp. in small mammals from natural, suburban and urban areas of Eastern Slovakia.

Rickettsiae of the spotted fever group are considered as emerging pathogens; ticks, fleas and mites are known to be their vectors. However, the prevalence and species diversity of rickettsiae in small mammals and the role of these hosts in the circulation of bacteria are much less studied. During 2014-2016, a total of 250 small mammals (Apodemus agrarius, Apodemus flavicollis, Apodemus uralensis, Myodes glareolus, Crocidura leucodon, Crocidura suaveolens, Micromys minutus, Microtus arvalis, Microtus subterraneus, Neomys fodiens and Sorex minutus) were captured in natural, suburban and urban habitats of eastern Slovakia. Ear biopsies of 245 individuals were examined for the presence of SFG rickettsiae by molecular methods. The overall prevalence of Rickettsia spp. in small mammals was 11%. The predominant species, Rickettsia helvetica was confirmed in the striped field mouse (A. agrarius), the yellow-necked mouse (A. flavicollis), the bank vole (M. glareolus) and the common vole (M. arvalis) in natural and suburban habitats, followed by Rickettsia sp. closely related to R. felis identified in A. flavicollis captured in a suburban habitat. Finally, R. slovaca was found in only one yellow-necked mouse (A. flavicollis) captured in a natural habitat, with the sympatric occurrence of Dermacentor marginatus and Dermacentor reticulatus ticks. We assume the presence of R. slovaca especially in sites with the occurrence of Dermacentor spp. All small mammals captured in the urban habitat tested were negative for the presence of rickettsiae. This study brings the first molecular evidence of R. slovaca in a rodent captured in Slovakia. Rickettsia sp. closely related to R. felis was first time detected in A. flavicollis in suburban site of Slovakia. The highest species diversity of rickettsiae was observed in A. flavicollis, and the highest prevalence of bacteria was recorded in M. glareolus. The highest occurrence of rickettsiae-positive small mammals was recorded during the spring and autumn months, May, June and September, respectively. This may be related with the seasonal activity of the tick vectors. This study confirms the long-term persistence of Rickettsia spp. in small mammals in natural and suburban habitats of Slovakia. Some rodent species that have a wider ecological valency may contribute to the maintenance, circulation and dissemination of rickettsiae within and out the natural foci more significantly than those species that have narrower relation to the certain type of habitat.