title: The enzootic life-cycle of Borrelia burgdorferi (sensu lato) and tick-borne rickettsiae: an epidemiological study on wild-living small mammals and their ticks from Saxony, Germany.
abstract: BACKGROUND
  Borrelia burgdorferi (sensu lato) and rickettsiae of the spotted fever group are zoonotic tick-borne pathogens. While small mammals are confirmed reservoirs for certain Borrelia spp., little is known about the reservoirs for tick-borne rickettsiae. Between 2012 and 2014, ticks were collected from the vegetation and small mammals which were trapped in Saxony, Germany. DNA extracted from ticks and the small mammals' skin was analyzed for the presence of Rickettsia spp. and B. burgdorferi (s.l.) by qPCR targeting the gltA and p41 genes, respectively. Partial sequencing of the rickettsial ompB gene and an MLST of B. burgdorferi (s.l.) were conducted for species determination.
  
  
  RESULTS
  In total, 673 small mammals belonging to eight species (Apodemus agrarius, n = 7; A. flavicollis, n = 214; Microtus arvalis, n = 8; Microtus agrestis, n = 1; Mustela nivalis, n = 2; Myodes glareolus, n = 435; Sorex araneus, n = 5; and Talpa europaea, n = 1) were collected and examined. In total, 916 questing ticks belonging to three species (Ixodes ricinus, n = 741; Dermacentor reticulatus, n = 174; and I. trianguliceps, n = 1) were collected. Of these, 474 ticks were further investigated. The prevalence for Rickettsia spp. and B. burgdorferi (s.l.) in the investigated small mammals was 25.3 and 31.2%, respectively. The chance of encountering Rickettsia spp. in M. glareolus was seven times higher for specimens infested with D. reticulatus than for those which were free of D. reticulatus (OR: 7.0; 95% CI: 3.3-14.7; P < 0.001). In total, 11.4% of questing I. ricinus and 70.5% of D. reticulatus were positive for Rickettsia spp. DNA of B. burgdorferi (s.l.) was detected only in I. ricinus (5.5%). Sequence analysis revealed 9 R. helvetica, 5 R. raoultii, and 1 R. felis obtained from 15 small mammal samples.
  
  
  CONCLUSIONS
  Small mammals may serve as reservoirs for Rickettsia spp. and B. burgdorferi (s.l.). While the prevalence for Rickettsia spp. in M. glareolus is most likely depending on the abundance of attached D. reticulatus, the prevalence for B. burgdorferi (s.l.) in small mammals is independent of tick abundance. Dermacentor reticulatus may be the main vector of certain Rickettsia spp. but not for Borrelia spp.
authors.affiliation: Institute of Animal Hygiene and Veterinary Public Health, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany. Anna.Obiegala@vetmed.uni-leipzig.de.
authors.forename: Anna
authors.initials: A
authors.lastname: Obiegala
authors.affiliation: Institute of Animal Hygiene and Veterinary Public Health, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany.|Department of Microbial Ecology and Environmental Protection, Institute of Genetics and Microbiology, University of Wrocław, Przybyszewskiego 63/77, 51-148, Wrocław, Poland.
authors.forename: Nina
authors.initials: N
authors.lastname: Król
authors.affiliation: Institute of Animal Hygiene and Veterinary Public Health, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany.
authors.forename: Carolin
authors.initials: C
authors.lastname: Oltersdorf
authors.affiliation: Institute of Animal Hygiene and Veterinary Public Health, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany.
authors.forename: Julian
authors.initials: J
authors.lastname: Nader
authors.affiliation: Institute of Animal Hygiene and Veterinary Public Health, University of Leipzig, An den Tierkliniken 1, 04103, Leipzig, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Pfeffer
mesh_terms: D041081:Anaplasma phagocytophilum / Q000235:genetics / Q000302:isolation & purification; D000818:Animals; D000835:Animals, Wild / Q000382:microbiology* / Q000469:parasitology; D025065:Borrelia burgdorferi / Q000235:genetics / Q000302:isolation & purification*; D004269:DNA, Bacterial / Q000235:genetics; D003870:Dermacentor / Q000235:genetics; D004197:Disease Reservoirs; D005858:Germany / Q000453:epidemiology; D018884:Ixodes / Q000235:genetics / Q000382:microbiology*; D008193:Lyme Disease / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D008322:Mammals / Q000382:microbiology* / Q000469:parasitology; D058885:Multilocus Sequence Typing; D012281:Rickettsia / Q000235:genetics / Q000302:isolation & purification*; D012282:Rickettsia Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*
chemical_list: D004269:DNA, Bacterial
keywords: Borrelia MLST; Dermacentor reticulatus; Ixodes ricinus; Myodes glareolus