Francisella tularensisSubspeciesholarcticaand Tularemia in Germany

Tularemia is a zoonotic disease caused byFrancisella tularensisa small, pleomorphic, facultative intracellular bacterium. In Europe, infections in animals and humans are caused mainly byFrancisella tularensissubspeciesholarctica. Humans can be exposed to the pathogen directly and indirectly through contact with sick animals, carcasses, mosquitoes and ticks, environmental sources such as contaminated water or soil, and food. So far,F. tularensissubsp.holarcticais the onlyFrancisellaspecies known to cause tularemia in Germany. On the basis of surveillance data, outbreak investigations, and literature, we review herein the epidemiological situation-noteworthy clinical cases next to genetic diversity ofF. tularensissubsp.holarcticastrains isolated from patients. In the last 15 years, the yearly number of notified cases of tularemia has increased steadily in Germany, suggesting that the disease is re-emerging. By sequencingF. tularensissubsp.holarcticagenomes, knowledge has been added to recent findings, completing the picture of genotypic diversity and geographical segregation ofFrancisellaclades in Germany. Here, we also shortly summarize the current knowledge about a newFrancisellaspecies (Francisellasp. strain W12-1067) that has been recently identified in Germany. This species is the secondFrancisellaspecies discovered in Germany.