The number of Bartonella species identified as zoonotic pathogens has increased considerably over the last decades. Pets have been recognised as a notable reservoir of Bartonella spp. whereas cats are known to act as the main reservoir for human infection with regard to Bartonella henselae, Bartonella clarridgeiae and Bartonella koehlerae.
Important diseases caused by Bartonella species in humans are Oroya fever (also known as Carrións disease, caused by Bartonella bacilliformis), trench fever, a louse-borne disease caused by Bartonella quintana and the cat-scratch disease (CSD) mainly caused by B. henselae with the domestic cat as the natural reservoir.
In dogs infected with Bartonella spp., similar disease manifestations as in human patients have been observed and thus dogs represent epidemiological sentinels for human exposure. However, the role of dogs as a source of human infection is less clear than it is for cats.