A DOUBLE ANTIBODY SANDWICH ELISA FOR RAPID DIAGNOSIS OF VIRUS-INFECTION AND TO MEASURE THE HUMORAL RESPONSE AGAINST INFECTIOUS BURSAL DISEASE ON CLINICAL MATERIAL

A double antibody sandwich ELISA (DAS-ELISA) was developed and employe d for simultaneous direct detection of infectious bursal disease virus (IBDV) from bursal samples and to measure the humoral response, using the same basic immunoreagents, The purified and non-purified antigen, capture antibody and chicken hyperimmune sera were prepared, and stan dardized for this purpose, The DAS-ELISA was applied to both 80 bursal suspensions and 224 corresponding serum samples from vaccinated and n on-vaccinated commercial hocks, Bursae samples were collected at 2 wee ks of age, and submitted to histological examination, virus isolation in specific pathogen-free chickens embryos, and the DAS-ELISA techniqu e, Serum titres obtained in indirect ELISA and serum neutralization te st were compared with those in DAS-ELISA, The agreement was 80% betwee n DAS-ELISA, and the conventional techniques, with high sensitivity (8 7%) and specificity (90%).