Density-dependent prevalence of Francisella tularensis in fluctuating vole populations, northwestern Spain

Tularemia in humans in northwestern Spain is associated with increases in vole populations. Prevalence of infection with Francisellatularensis in common voles increased to 33% during a vole population fluctuation. This finding confirms that voles are spillover agents for zoonotic outbreaks. Ecologic interactions associated with tularemia prevention should be considered.