Tularemia in humans in northwestern Spain is associated with increases in vole populations. Prevalence of infection with Francisella tularensis 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.
Keywords: Francisella tularensis; Spain; bacteria; density-dependent prevalence; fluctuating populations; outbreaks; prevalence; tularemia; voles; wildlife; zoonoses.