We detected 3 Bartonella species in wild rabbit fleas from Colorado, USA: B. vinsonii subsp. berkhoffii (n = 16), B. alsatica (n = 5), and B. rochalimae (n = 1). Our results support the establishment of the zoonotic agent B. alsatica in North America.
Keywords: Bartonella; Colorado; Siphonaptera; United States; bacteria; disease ecology; lagomorpha; rabbit fleas; vector-borne infections; zoonoses.