Evaluación de la prueba de inmunoabsorbancia ligad AA enzimas (Elisa) en el diagnóstico de la tuberculosis bovina

The use of an indirect enzyme-linked immunosorbent assay (ELISA) for diagnosis ofbovine tuberculosis infection was evaluated. Protein Purified Derivate (PPD) was used as antigen providing an alternative to the traditional skin test. Sensitivity, specificity, and both positive and negative predictive values were detennined for the PPD ELISA test. One hundred and three sera from a non-endemic area (Arizona, USA) were used to calculate specificity, and fifty-three sera from necropsy positive animals (with both active and sub-clinical TB) were used to calculate sensitivity. Thirty-seven positive control sera also yielded positive results, giving a sensitivity of69.81 ± 12.36%. Similarly, 74 ofthe 103 negative control sera were also negative to the test, yielding a specificity of 71.84 ± 8.69%. The positive and negative predictive values were 56.06 ± 11.97% and 81.22 ± 7.90% respectively.