Comparison of three immunoassays for the rapid detection of bovine respiratory syncytial virus.

Three enzyme-linked immunosorbent assays (EIA) designed for the detection of human respiratory syncytial virus (RSV) were evaluated for the detection of bovine respiratory syncytial virus (BRSV) in bovine lungs and the results were compared with those obtained by a direct fluorescent antibody assay (DFA). The EIA tests used were Directigen EIA, Kallestad Pathfinder EIA, and Abbott RSV EIA. Homogenates of lung tissues obtained from 64 cattle that had died of respiratory disease were used; 32 were positive by DFA and 32 were negative. All EIA's varied in the amount of labor and time involved but their relative sensitivities were similar ranging between 59 and 66% when compared with DFA. The specificity of Pathfinder EIA was lower than those of the Directigen and Abbott tests. The overall agreement between the three EIA's and the DFA was 66-77% indicating that DFA is still the test of choice for detecting BRSV infection in lung tissues of cattle.