Serological survey and risk factors far brucellosis due to Brucella canis in dogs of the Santana de Parnaiba municipality, State of Sao Paulo.

The prevalence of brucellosis due to Brucella canis was investigated in dogs of the Santana de Pamaiba county, State of Sao Paulo, southeastern Brazil, and the risk factors for infection were analyzed. For this purpose, 410 blood samples were collected from dogs during the rabies vaccination campaign, in August 1999. The agar gel immunodiffusion test (AGID), using lipopolysaccharides and protein antigens from Brucella ovis, strain Reo 198, was applied first as a screening test on normal sera, and secondly, for confirmation. The same AGID test was applied to sera treated previously with 2-mercaptoethanol (ME-AGID). The complement fixation test (CFT), using B. ovis antigen, strain 63/290, was applied also as a confirmatory test. For the prevalence analysis, animals presenting positive results in both ME-AGID and CFT were considered positive. The prevalence of brucellosis due to B. canis was 2.2% (95% C.I. = 1.01-4.13%). Dogs that were allowed by their owners to stay free outside their home had a higher risk for contracting B. canis infection, with an odds ratio value of 8.73 (95% U. =: 1.48-51.55) and p=0.04.