title: Spotted fever Rickettsia species in Hyalomma and Ixodes ticks infesting migratory birds in the European Mediterranean area.
abstract: BACKGROUND
  A few billion birds migrate annually between their breeding grounds in Europe and their wintering grounds in Africa. Many bird species are tick-infested, and as a result of their innate migratory behavior, they contribute significantly to the geographic distribution of pathogens, including spotted fever rickettsiae. The aim of the present study was to characterize, in samples from two consecutive years, the potential role of migrant birds captured in Europe as disseminators of Rickettsia-infected ticks.
  
  
  METHODS
  Ticks were collected from a total of 14,789 birds during their seasonal migration northwards in spring 2009 and 2010 at bird observatories on two Mediterranean islands: Capri and Antikythira. All ticks were subjected to RNA extraction followed by cDNA synthesis and individually assayed with a real-time PCR targeting the citrate synthase (gltA) gene. For species identification of Rickettsia, multiple genes were sequenced.
  
  
  RESULTS
  Three hundred and ninety-eight (2.7%) of all captured birds were tick-infested; some birds carried more than one tick. A total number of 734 ticks were analysed of which 353 ± 1 (48%) were Rickettsia-positive; 96% were infected with Rickettsia aeschlimannii and 4% with Rickettsia africae or unidentified Rickettsia species. The predominant tick taxon, Hyalomma marginatum sensu lato constituted 90% (n = 658) of the ticks collected. The remaining ticks were Ixodes frontalis, Amblyomma sp., Haemaphysalis sp., Rhipicephalus sp. and unidentified ixodids. Most ticks were nymphs (66%) followed by larvae (27%) and adult female ticks (0.5%). The majority (65%) of ticks was engorged and nearly all ticks contained visible blood.
  
  
  CONCLUSIONS
  Migratory birds appear to have a great impact on the dissemination of Rickettsia-infected ticks, some of which may originate from distant locations. The potential ecological, medical and veterinary implications of such Rickettsia infections need further examination.
authors.forename: Katarina
authors.initials: K
authors.lastname: Wallménius
authors.forename: Christos
authors.initials: C
authors.lastname: Barboutis
authors.forename: Thord
authors.initials: T
authors.lastname: Fransson
authors.forename: Thomas G T
authors.initials: TG
authors.lastname: Jaenson
authors.forename: Per-Eric
authors.initials: PE
authors.lastname: Lindgren
authors.forename: Fredrik
authors.initials: F
authors.lastname: Nyström
authors.forename: Björn
authors.initials: B
authors.lastname: Olsen
authors.forename: Erik
authors.initials: E
authors.lastname: Salaneck
authors.affiliation: Department of Medical Sciences, Section of Clinical Microbiology, Uppsala University, Uppsala, Sweden. kenneth.nilsson@medsci.uu.se.
authors.forename: Kenneth
authors.initials: K
authors.lastname: Nilsson
mesh_terms: D025041:Animal Migration; D000818:Animals; D001715:Bird Diseases / Q000382:microbiology / Q000469:parasitology*; D001717:Birds; D026863:Ixodidae / Q000382:microbiology*; D019083:Mediterranean Region / Q000453:epidemiology; D012281:Rickettsia / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D013984:Tick Infestations / Q000453:epidemiology / Q000662:veterinary*