Birds and Borrelia.

After several years of controversy, the contribution of birds in the ecology of Borrelia burgdorferi sensu lato (sl) has become more and more obvious on the three continents where the pathogens are distributed. Evidence of the reservoir competence of particular bird species has been obtained using tick xenodiagnosis. B. burgdorferi sl circulates not only in terrestrial environment involving Ixodes ricinus and undergrowth-frequenting birds but also in marine environment involving I. uriae and seabirds. Migrating birds contribute to the spread of B. burgdorferi sl and of infected tick vectors along migration routes.