title: Melting pot of tick-borne zoonoses: the European hedgehog contributes to the maintenance of various tick-borne diseases in natural cycles urban and suburban areas.
abstract: European hedgehogs (Erinaceus europaeus) are urban dwellers and host both Ixodes ricinus and Ixodes hexagonus. These ticks transmit several zoonotic pathogens like Borrelia burgdorferi (sensu lato), Anaplasma phagocytophilum, Rickettsia helvetica, Borrelia miyamotoi and "Candidatus Neoehrlichia mikurensis". It is unclear to what extent hedgehogs in (sub) urban areas contribute to the presence of infected ticks in these areas, which subsequently pose a risk for acquiring a tick-borne disease. Therefore, it is important to investigate to what extent hedgehogs contribute to the enzootic cycle of these tick-borne pathogens, and to shed more light at the mechanisms of the transmission cycles involving hedgehogs and both ixodid tick species.
  
  
  
  Engorged ticks from hedgehogs were collected from (sub) urban areas via rehabilitating centres in Belgium. Ticks were screened individually for presence of Borrelia burgdorferi (sensu lato), Borrelia miyamotoi, Anaplasma phagocytophilum, Rickettsia helvetica and "Candidatus Neoehrlichia mikurensis" using PCR-based methods. Infection rates of the different pathogens in ticks were calculated and compared to infection rates in questing ticks.
  
  
  
  Both Ixodes hexagonus (n = 1132) and Ixodes ricinus (n = 73) of all life stages were found on the 54 investigated hedgehogs. Only a few hedgehogs carried most of the ticks, with 6 of the 54 hedgehogs carrying more than half of all ticks (624/1205). Borrelia miyamotoi, A. phagocytophilum, R. helvetica and B. burgdorferi genospecies (Borrelia afzelii, Borrelia bavariensis and Borrelia spielmanii) were detected in both I. hexagonus and I. ricinus. Anaplasma phagocytophilum, R. helvetica, B. afzelii, B. bavariensis and B. spielmanii were found significantly more in engorged ticks in comparison to questing I. ricinus.
  
  
  
  European hedgehogs seem to contribute to the spread and transmission of tick-borne pathogens in urban areas. The relatively high prevalence of B. bavariensis, B. spielmanii, B. afzelii, A. phagocytophilum and R. helvetica in engorged ticks suggests that hedgehogs contribute to their enzootic cycles in (sub) urban areas. The extent to which hedgehogs can independently maintain these agents in natural cycles, and the role of other hosts (rodents and birds) remain to be investigated.
authors.affiliation: Centre for Infectious Disease Control, National Institute of Public Health and Environment (RIVM), Antonie van Leeuwenhoeklaan 9, 3720 BA, Bilthoven, The Netherlands.
authors.forename: Setareh
authors.initials: S
authors.lastname: Jahfari
authors.affiliation: Forest and Nature Laboratory, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, 9090, Melle-Gontrode, Belgium.
authors.forename: Sanne C
authors.initials: SC
authors.lastname: Ruyts
authors.affiliation: Centre for Infectious Disease Control, National Institute of Public Health and Environment (RIVM), Antonie van Leeuwenhoeklaan 9, 3720 BA, Bilthoven, The Netherlands.
authors.forename: Ewa
authors.initials: E
authors.lastname: Frazer-Mendelewska
authors.affiliation: Centre for Infectious Disease Control, National Institute of Public Health and Environment (RIVM), Antonie van Leeuwenhoeklaan 9, 3720 BA, Bilthoven, The Netherlands.
authors.forename: Ryanne
authors.initials: R
authors.lastname: Jaarsma
authors.affiliation: Forest and Nature Laboratory, Department of Forest and Water Management, Ghent University, Geraardsbergsesteenweg 267, 9090, Melle-Gontrode, Belgium.
authors.forename: Kris
authors.initials: K
authors.lastname: Verheyen
authors.affiliation: Centre for Infectious Disease Control, National Institute of Public Health and Environment (RIVM), Antonie van Leeuwenhoeklaan 9, 3720 BA, Bilthoven, The Netherlands. hein.sprong@rivm.nl.
authors.forename: Hein
authors.initials: H
authors.lastname: Sprong
mesh_terms: D000818:Animals; D001419:Bacteria / Q000145:classification / Q000302:isolation & purification; D001530:Belgium / Q000453:epidemiology; D002947:Cities; D004197:Disease Reservoirs / Q000469:parasitology*; D006364:Hedgehogs / Q000469:parasitology*; D018884:Ixodes / Q000382:microbiology*; D007814:Larva; D009758:Nymph; D013383:Suburban Population; D013984:Tick Infestations / Q000453:epidemiology / Q000469:parasitology / Q000662:veterinary; D017282:Tick-Borne Diseases / Q000453:epidemiology / Q000382:microbiology* / Q000469:parasitology; D015047:Zoonoses
keywords: Anaplasma phagocytophilum; Borrelia burgdorferi (sensu lato); Borrelia miyamotoi; Erinaceus europaeus; European hedgehog; Ixodes hexagonus; Ixodes ricinus; Lyme borreliosis; Rickettsia helvetica; “Candidatus Neoehrlichia mikurensis”