title: Pathogens in ticks collected from dogs in Berlin/Brandenburg, Germany.
abstract: BACKGROUND
  Tick-borne diseases are a major health risk for humans and dogs. In addition to collection and analysis of questing ticks, analysis of host-associated ticks for the presence of pathogens is a valuable method to gain insight into transmission patterns of tick-borne diseases.
  
  
  METHODS
  Ticks were collected from dogs living in the Berlin/Brandenburg area. The three tick species Ixodes ricinus, Ixodes hexagonus and Dermacentor reticulatus were examined for the presence of Babesia spp., Borrelia spp., Rickettsia spp. and Anaplasmataceae. Conventional PCR followed by sequencing was used for pathogen detection and characterization.
  
  
  RESULTS
  Babesia spp. were found in 2.5% and 3% of I. ricinus and I. hexagonus, respectively. Sequencing revealed the presence of Babesia microti, Babesia capreoli and Babesia venatorum. D. reticulatus were free of Babesia canis. Rickettsia spp. were detected in 61% of I. ricinus, 44% of I. hexagonus and 39% of D. reticulatus. Specifically detected were Rickettsia raoulti in D. reticulatus and I. hexagonus, Rickettsia helvetica in I. ricinus and I. hexagonus and Rickettsia monacensis in I. hexagonus. Anaplasma phagocytophilum and Candidatus Neoehrlichia mikurensis have been reported previously in I. ricinus (6.5% and 4.3%, respectively) and I. hexagonus (3.9% and 5.9%). Borrelia spp. were found in 11.6% of I. ricinus and 11.2% of I. hexagonus. Subsequent genospecies analysis revealed Borrelia afzelii, Borrelia garinii, Borrelia burgdorferi sensu stricto and Borrelia miyamotoi. Simultanous presence of more than one pathogen was found in 20% of I. ricinus and in 59% of I. hexagonus whereas the total frequency of any pathogen was 65% in I. ricinus, 59% in I. hexagonus and 64% in D. reticulatus. Ticks in which A. phagocytophilum was detected had a significantly increased risk of also containing Rickettsia. Ticks harbouring a pathogen had significantly higher scutal indices than ticks without presence of any pathogen.
  
  
  CONCLUSIONS
  Frequencies of potential human or canine pathogens in ticks were considerable and DNA of all four groups of pathogens was detected. Differences in scutal indices might suggest that pathogens are frequently taken up by ticks when feeding on dogs in Berlin/Brandenburg.
authors.affiliation: Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany. cecileschreiber@googlemail.com.|Small Animal Clinic, Freie Universität Berlin, Berlin, Germany. cecileschreiber@googlemail.com.
authors.forename: Cécile
authors.initials: C
authors.lastname: Schreiber
authors.affiliation: Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany. juergen.kruecken@fu-berlin.de.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Krücken
authors.affiliation: Small Animal Clinic, Freie Universität Berlin, Berlin, Germany. beck.stephanie@aol.com.
authors.forename: Stephanie
authors.initials: S
authors.lastname: Beck
authors.affiliation: Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany. denny.maaz@fu-berlin.de.|Institute of Immunology, Freie Universität Berlin, Berlin, Germany. denny.maaz@fu-berlin.de.
authors.forename: Denny
authors.initials: D
authors.lastname: Maaz
authors.affiliation: Bayer Vital GmbH, Leverkusen, Germany. stefan.pachnicke@bayer.com.
authors.forename: Stefan
authors.initials: S
authors.lastname: Pachnicke
authors.affiliation: Bayer Animal Health GmbH, Monheim, Germany. klemens.krieger@bayer.com.
authors.forename: Klemens
authors.initials: K
authors.lastname: Krieger
authors.affiliation: Institute for Statistics and Economy, Freie Universität Berlin, Berlin, Germany. marcus.gross@fu-berlin.de.
authors.forename: Marcus
authors.initials: M
authors.lastname: Gross
authors.affiliation: Small Animal Clinic, Freie Universität Berlin, Berlin, Germany. barbara.kohn@fu-berlin.de.
authors.forename: Barbara
authors.initials: B
authors.lastname: Kohn
authors.affiliation: Institute for Parasitology and Tropical Veterinary Medicine, Freie Universität Berlin, Berlin, Germany. gvsamson@fu-berlin.de.
authors.forename: Georg
authors.initials: G
authors.lastname: von Samson-Himmelstjerna
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D004283:Dog Diseases / Q000453:epidemiology / Q000469:parasitology*; D004285:Dogs; D005858:Germany / Q000453:epidemiology; D006801:Humans; D026863:Ixodidae / Q000382:microbiology*; D013984:Tick Infestations / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary*; D017282:Tick-Borne Diseases / Q000453:epidemiology / Q000382:microbiology; D015047:Zoonoses