title: Campylobacter jejuni sequence types show remarkable spatial and temporal stability in Blackbirds.
abstract: BACKGROUND
  The zoonotic bacterium Campylobacter jejuni has a broad host range but is especially associated with birds, both domestic and wild. Earlier studies have indicated thrushes of the genus Turdus in Europe to be frequently colonized with C. jejuni, and predominately with host-associated specific genotypes. The European Blackbird Turdus merula has a large distribution in Europe, including some oceanic islands, and was also introduced to Australia by European immigrants in the 1850s.
  
  
  METHODS
  The host specificity and temporal stability of European Blackbird C. jejuni was investigated with multilocus sequence typing in a set of isolates collected from Sweden, Australia, and The Azores.
  
  
  RESULTS
  Remarkably, we found that the Swedish, Australian, and Azorean isolates were genetically highly similar, despite extensive spatial and temporal isolation. This indicates adaptation, exquisite specificity, and stability in time for European Blackbirds, which is in sharp contrast with the high levels of recombination and mutation found in poultry-related C. jejuni genotypes.
  
  
  CONCLUSIONS
  The maintenance of host-specific signals in spatially and temporally separated C. jejuni populations suggests the existence of strong purifying selection for this bacterium in European Blackbirds.
authors.affiliation: Section for Zoonotic Ecology and Epidemiology, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), School of Natural Sciences, Linnaeus University, Kalmar, Sweden; petra.griekspoor@lnu.se.
authors.forename: Petra
authors.initials: P
authors.lastname: Griekspoor
authors.affiliation: Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Newcastle, Australia.
authors.forename: Philip M
authors.initials: PM
authors.lastname: Hansbro
authors.affiliation: Section for Zoonotic Ecology and Epidemiology, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), School of Natural Sciences, Linnaeus University, Kalmar, Sweden.|Section of Infectious Diseases, Department of Medical Sciences, Uppsala University, Uppsala, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Waldenström
authors.affiliation: Section of Infectious Diseases, Department of Medical Sciences, Uppsala University, Uppsala, Sweden.|Zoonosis Science Center, IMBIM, Uppsala University, Uppsala, Sweden.
authors.forename: Björn
authors.initials: B
authors.lastname: Olsen
keywords: Blackbird; Campylobacter jejuni; MLST; gastrointestinal pathogen; population structure