Monoclonal antibody based blocking ELISA for the diagnosis of infectious bursal disease virus infection in chickens

Infectious bursal disease (IBD) is a contagious lymphocidal viral infection of young chickens controlled by vaccination of parent stock followed by that of progeny chickens. The day of vaccination of young chickens depends upon the level of existing anti IBDV maternal antibodies in the chickens. In order to determine the level of anti-IBD maternal antibodies in chickens, a double antibody sandwich blocking ELISA using anti-IBDV monoclonal antibody as virus capturing antibody was developed. The performance of sandwich blocking ELISA was compared with that of polyclonal antibody based ELISA and serum neutralization test (SNT). A correlation coefficient of 0.84 was found between SNT and monoclonal antibody based ELISA, 0.81 between SNT and polyclonal antibody based ELISA and 0.93 between monoclonal and polyclonal antibody based ELISA. The monoclonal antibody based ELISA was transformed into a single dilution ELISA for application in testing of a large number of sera samples for anti-IBDV antibodies. The single dilution ELISA showed a correlation coefficient of 0.76 with 50% end point ELISA which is statistically significant at 1% level of significance.