Bartonellosis
• Bartonellosis is an emerging, zoonotic, vector-borne infectious disease of cats, dogs, other animals, and humans. • Causes: The most common species reported in cats are Bartonella henselae, Bartonella clarridgeiae, and Bartonella koehlerae, whereas dogs are most often infected with B. henselae and Bartonella vinsonii subsp. berkhoffii. • Geographic Distribution: Worldwide, with the highest prevalence in humid subtropical and tropical regions. • Major Mode of Transmission: Fleas (Ctenocephalides felis) (through flea fecal contamination of wounds); possibly other flea species (such as Pulex spp.) and other vectors such as lice, biting flies, mites, and ticks. Blood transfusion transmission occurs experimentally. • Clinical Signs: In dogs, signs that relate to infective endocarditis (lethargy, fever, cardiac murmur, cough, tachypnea, lameness, neurologic) are the most frequent and well understood. Cats are commonly healthy carriers; however, Bartonella can also cause fever, endocarditis, myocarditis, and transient lymphadenomegaly in cats and may cause (or contribute to) other systemic inflammatory disorders. • Differential Diagnoses: Dogs: other bacterial causes of endocarditis; other vector-borne diseases such as ehrlichiosis, anaplasmosis, borreliosis, and babesiosis; and immune-mediated inflammatory diseases. Cats: major differential diagnoses are other bacterial causes of endocarditis, other systemic inflammatory diseases, and other causes of lymphadenomegaly. • Human Health Significance: Bartonella causes cat scratch disease and other less common disorders, including endocarditis, in immunocompetent humans as well as vasoproliferative disorders (known as bacillary angiomatosis or peliosis) in immunocompromised humans.
