Validation of enzyme-linked immunosorbent assays for the diagnosis of bovine brucellosis.

The purpose of this study was to evaluate the performance of the indirect enzyme immunoassay (IELISA) and the competitive enzyme immunoassay (CELISA) for the diagnosis of bovine brucellosis in comparison to conventional serological tests routinely used in Argentina. Serum samples (n = 3500), from Brucella-free herds, from vaccinated cattle and from naturally infected cattle, were tested by the following tests: buffered antigen agglutination test (BPAT), rose bengal test (RBT), 2-mercaptoethanol test (2-ME), complement fixation test (CFT), IELISA and CELISA. Sensitivity and specificity of the BPAT, RBT, IELISA and CELISA were determined relative to the 2-ME and the CFT. The CELISA was considered suitable for eliminating most serological reactions of vaccinated animals and was more specific than the other tests. The results indicate the potential use of the CELISA as a complementary assay in the brucellosis control and eradication program in Argentina and other countries, where Brucella abortusstrain 19 vaccination is mandatory.