[Prevalence of Bartonella henselae in stray and domestic cats in different Italian areas: evaluation of the potential risk of transmission of Bartonella to humans].

Bartonella henselae is the major etiological agent of Cat Scratch Disease in humans. Cats act as the natural reservoir of B. henselae and can transmit the infection to humans by bite or scratch. The diffusion of B. henselae was evaluated by seroprevalence and bacteremic status in different stray cat populations located in nine areas of Northern Italy. A total of 1585 cats were tested by blood culture and 361 (23%) resulted bacteremic; 1416 out off 1585 cats were also tested for Bartonella henselae antibodies and 553 (39%) resulted seropositive. The molecular typing of the isolates showed that 26% of bacteremic cats were infected with B. henselae type I, 52% with B. henselae type II, 16% were co-infected with both and 5% infected with B. Clarridgeiae. Moreover 165 domestic cats were tested by blood culture and serological test (IFA test cut-off: 1:64). 35 cats (21%) resulted bacteremic and 49 (43.5%) were seropositive. The molecular typing of the Bartonella isolates of the domestic cats showed that 45% of bacteremic cats were infected with B. henselae type I, 36.5% with B. henselae type II, 12% were coinfected with both and 6% infected with B. Clarridgeiae. For a completely evaluation of health status of the cat for B. henselae infection, the authors suggest both blood culture and serological tests. Nevertheless a nonbacteremic cat with positive serology result should be reevaluated for possible recurrent bacteremia.