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Veterinary bacteriology: information about important bacteria
Veterinary bacteriology

Species/Subspecies: Francisella tularensis subsp. holarctica
Categories: Zoonotic; notifiable diseases and bacteria
Etymology: Genus name: named after the American bacteriologist Edward Francis, who has studied tularemia.
Species epithet: refers to Tulare county in California, where the disease was first described in rodents in year 1912.
Subspecies epithet: may be found in all arctic regions.
Significance:Is predominantly found in Asia and Europe, but occasionally also in North America. This subspecies is less virulent than subsp. tularensis.
  [Very important]   
Type Strain: GIEM 503.
Macromorphology (smell):
Micromorphology: Coccoid or short nonmotile rods.
Gram +/Gram -:G-
Metabolism: Strict aerobic
Other Enzymes: Tryptophanase - (= indole -), ureas -.
Spec. Char.: Facultatively intracellular. May penetrate intact skin.
Vector: Mosquitoes and ticks
HostsDiseaseClinical picture
HumansTularemiFever, headache and nausea. Local swelling (abscess) at the site of infection and nearest lymph node.
Virulence Factors: The capsule can be a virulence factor.
Genome Sequence:
Acc-noStrainSize (bp)Genome
NC_007880 LVS 1 895 994 1c + 0 

16S rRNA Seq.:
Acc-noStrainNumber of NTOperon
AJ698864 FSC 090 1 465 

Nine species have been described within genus Francisella and this genus is related to Coxiella spp. and Legionella spp.
Legislation: Tularemia is notifiable in Sweden. Francisella tularensis belongs to category A as a potential bioterrorism agent according to NIAID.
Comment:Common in Sweden. The subspecies holarctica is less virulent than the subspecies tularensis.
Reference(s): No. 25


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