This assay was carried out in the Virus Research Division Laboratory of the National Veterinary Research Institute (NVRI), Vom, Plateau State using avian influenza virus antibody test kit (ID.vet Innovative Diagnostics, 310, rue Louis Pasteur – Grabels – France). Test serum samples were subjected to competitive ELISA following the manufacturers’ instructions (ID Screen Influenza H5 antibody competition protocol). The optical density (OD) values were measured and recorded at 450 nm wavelength using ELISA microtitre plate reader (Thermo Scientific, Multiskan Ex). Competition percentage (S/N %) of each sample was calculated as shown below: