Evaluación comparativa de la prueba de fluorescencia polarizada como diagnóstico confirmatorio de la brucelosis bovina en la provincia del Carchi, Ecuador

The present study was performed to evaluate and compare the Fluorescence Polarization Assay (FPA) as a confirmatory test for bovine brucellosis in the province of Carchi - Ecuador, comparing it with a immuno-enzymatic assay cELISA which is a test prescribed as confirmatory diagnosis in the National Bovine Brucellosis Control Program for Ecuador. The study was carried out in the province of Carchi, which is located in the north of Ecuador in blood serum samples (n = 1000) obtained from female bovines older than 2 years with unknown health status and vaccination, belonging to 94 Agricultural Production Units. The serum was analyzed by the Rose Bengal test (RB) and the positive results were confirmed through cELISA, and then compared with the FPA considering as cutoff ≥ 89.9 mP. Of the total samples analyzed with RB, 94 were positive. Of these positive samples 77 were confirmed for both cELISA and FPA. In addition, 11 samples that were positive for RB and cELISA were negative for FPA. Likewise, 6 samples positive for RB were classified as negative for both cELISA and FPA. The concordance analysis showed that there is a moderate concordance between the cELISA and the FPA with an index of 0.472 (95% CI 0.179 – 0.765) between the two tests.