We detected Francisella tularensis and Bartonella spp. in fleas parasitizing common voles (Microtus arvalis) from northwestern Spain; mean prevalence was 6.1% for F. tularensis and 51% for Bartonella spp. Contrasted vector-host associations in the prevalence of these bacteria suggest that fleas have distinct roles in the transmission cycle of each pathogen in nature.
Keywords: Bartonella spp; Francisella tularensis; Microtus arvalis; Spain; bacteria; ectoparasites; flea-borne diseases; parasites; rodent-borne diseases; small rodents; transmission routes; vector; vector-borne infections; zoonoses.