Development of an enzyme-linked immunosorbent assay for the detection of antibodies against malignant catarrhal fever viruses in cattle serum.

Malignant catarrhal fever (MCF) is a sporadic but fatal lymphoproliferative viral disease of cattle, deer and other ruminants. The causative agents are highly-cell-associated herpesviruses of the subfamily gammaherpesvirinae. In this study, an ELISA (WC11-ELISA) was developed to detect antibody to malignant catarrhal fever virus (MCFV) in cattle serum and compared to the commercially produced competitive-inhibition ELISA (CI-ELISA). Crude lysate antigen from alcelaphine herpesvirus-1 strain WC11 was bound to 96-well microplates and used to capture antibodies to MCFV. Dilutions of test sera were added to wells containing bound MCF antigen and control wells containing uninfected cell lysates. A horseradish peroxidase-labelled rabbit-anti-bovine IgG conjugate detected antibodies to MCF, and the results were expressed as absorbance readings at 450 nm. Samples were selected blind from cattle sera which had been sent to the laboratory for diagnostic testing for MCFV antibodies and were tested in both the WC11-ELISA and the CI-ELISA. Good agreement between the WC11-ELISA and CI-ELISA test (k=0.86, n=95) results was found.