On which continents is Francisella tularensis subsp. holarctica mainly found?

Francisella tularensis subsp. holarctica is primarily associated with regions in North America, Europe, and Asia. This subspecies is responsible for tularemia, a disease that is found in various animal reservoirs, particularly in wildlife. In North America, it is frequently isolated from rodents, lagomorphs, and various other mammals, while in Europe and Asia, it has a similar ecological niche.

The prevalence of this pathogen in these three continents is attributed to the favorable environmental conditions for its reservoirs and vectors, including various species of ticks and deer flies that transmit the bacteria. Thus, its distribution aligns closely with these specific regions, supporting the conclusion that North America, Europe, and Asia are the primary locales for Francisella tularensis subsp. holarctica.