The phylogeographic pattern of Francisella tularensis in Sweden indicates a Scandinavian origin of Eurosiberian tularaemia
Open Access
- 23 November 2012
- journal article
- research article
- Published by Wiley in Environmental Microbiology
- Vol. 15 (2), 634-645
- https://doi.org/10.1111/1462-2920.12052
Abstract
Previous studies of the causative agent of tularaemia, Francisella tularensis have identified phylogeographic patterns suggestive of environmental maintenance reservoirs. To investigate the phylogeography of tularaemia in Sweden, we selected 163 clinical isolates obtained during 1995–2009 in 10 counties and sequenced one isolate's genome to identify new genetic markers. An improved typing scheme based on two indels and nine SNPs was developed using hydrolysis or TaqMan MGB probe assays. The results showed that much of the known global genetic diversity of F. tularensis subsp. holarctica is present in Sweden. Thirteen of the 163 isolates belonged to a new genetic group that is basal to all other known members of the major genetic clade B.I, which is spread across the Eurosiberian region. One hundred and twenty-five of the 163 Swedish isolates belonged to B.I, but individual clades' frequencies differed from county to county (P < 0.001). Subsequent analyses revealed a correlation between genotype variation over time and recurrent outbreaks at specific places, supporting the ‘maintenance reservoir’ environmental maintenance hypothesis. Most importantly, the findings reveal the presence of diverse source populations of F. tularensis subsp. holarctica in Sweden and suggest a historical spread of the disease from Scandinavia to other parts of Eurosiberia.This publication has 24 references indexed in Scilit:
- Phylogeography of Francisella tularensis subspecies holarctica from the country of GeorgiaBMC Microbiology, 2011
- MEGA5: Molecular Evolutionary Genetics Analysis Using Maximum Likelihood, Evolutionary Distance, and Maximum Parsimony MethodsMolecular Biology and Evolution, 2011
- progressiveMauve: Multiple Genome Alignment with Gene Gain, Loss and RearrangementPLOS ONE, 2010
- A Real-Time PCR Array for Hierarchical Identification of Francisella IsolatesPLOS ONE, 2009
- Molecular Evolutionary Consequences of Niche Restriction in Francisella tularensis, a Facultative Intracellular PathogenPLoS Pathogens, 2009
- Phylogeography of Francisella tularensis : Global Expansion of a Highly Fit CloneJournal of Bacteriology, 2009
- Nonrandom Distribution of Vector Ticks (Dermacentor variabilis) Infected by Francisella tularensisPLoS Pathogens, 2009
- ABySS: A parallel assembler for short read sequence dataGenome Research, 2009
- Genomic Deletion Marking an Emerging Subclone of Francisella tularensis subsp. holarctica in France and the Iberian PeninsulaApplied and Environmental Microbiology, 2007
- Canonical Insertion-Deletion Markers for Rapid DNA Typing ofFrancisella tularensisEmerging Infectious Diseases, 2007