EVALUATION OF THE SUITABILITY OF A COMMERCIAL BOVINE VIRAL DIARRHEA VIRUS-ANTIGEN CAPTURE ELISA FOR DIAGNOSTIC TESTING

The suitability of a commercial bovine viral diarrhoea virus (BVDV) an tigen capture enzyme-linked immunosorbent assail (ELISA) for routine d iagnostic testing of bovine serum samples was evaluated by comparing t he ELISA results of 214 sera with those obtained after two passages in roller tube cultures of fetal bovine lung cells and immunofluorescent staining using fluorescein isothiocyanate-conjugated hyperimmune BVDV antiserum. In addition, 208 of these samples were tested by virus iso lation in a microtitre system followed by indirect immunoperoxidase st aining using a pool of two non-competing pestivirus specific monoclona l antibodies. The sensitivity of the ELISA compared with virus isolati on followed by immunofluorescent and immunoperoxidase staining was 47. 8 and 45.8%, respectively. The corresponding figures of specificity an d over-all correlation were 95.3 and 95.1%, and 90.2 and 89.4%. Twenty -two of 24 pestivirus isolates from the positive blood samples were ty ped as BVDV-like by monoclonal antibodies, indicating that the poor se nsitivity of the ELISA was not due to the presence of atypical pestivi ruses in the test sample. These results suggest that this ELISA is not suitable for testing blood samples for BVDV in a diagnostic laborator y.