Bartonella henselae infections are now recognised as being among the most common zoonoses acquired from companion animals in the developed world. B. henselae is transmitted between cats by the cat flea Ctenocephalides felis. Humans can be infected with B. henselae by a scratch or bite from an infected cat. Infection can give rise to a wide range of clinical manifestations including, most commonly, cat scratch disease, which is characterised by a unilateral regional lymphadenopathy, and also persistent bacteraemia and fever, endocarditis and bacillary angiomatosis. Domestic and wild cat species serve as reservoir hosts for B. henselae, with the bacterium persisting within circulating erythrocytes; surveys of domestic cat populations around the world have shown an infection prevalence of, typically 5-20% in temperate regions, rising to 50% in warmer climates. Infections in humans are diagnosed on the basis of clinical presentation and/or using laboratory methods including serology and specific PCRs. Although isolation of B. henselae from cat blood is straightforward, its recovery from infected human tissues is far more difficult. An MLST scheme for B. henselae was first described in 2003 (Iredell et al., 2003).
Iredell J, Blanckenberg D, Arvand M, Grauling S, Feil EJ and Birtles RJ. Characterization of the natural population of Bartonella henselae by multilocus sequence typing. J Clin Microbiol 2003, 41:5071-5079.