Evaluation of ELISA and VNT for sheeppox virus antibody detection and development of an immunoenzymatic quantitative method

Vaccination against sheep pox (SPV) is the most efficient tool to control spread of the disease and virus neutralization test (VNT) is the gold standard for vaccination monitoring. In the presented study, we evaluated the use of ELISA and VNT for quantification of SPV humoral response post vaccination. Results confirmed that VNT is more sensitive since ELISA did not detect 22% of positive tested sera, and VNT weak positive sera were either negative or doubtful by ELISA. The most sensitive cells to perform VNT were ESH-L instead of Lamb primary cells. We also investigated immunoperoxidase IPMA and immunofluorescence IFA assays for detection of SPV specific antibodies and IPMA showed higher antibody titers comparatively to IFA. VNT using ESH-L cells with immune-enzymatic revelation provide specific quantitative SPV antibody titers, easier to read in shorter incubation time.