The detection of specific IgM to infectious bronchitis virus in chicken serum using an ELISA.

An ELISA is reported for the detection of specific IgM to infectious bronchitis virus (IBV) in serum samples from IBV-infected chickens. Both IgM and IgG antibodies to a heterologous, as well as to a homologous, strain could be detected by the ELISA. The IgM response was both rapid and transient, suggesting that its detection could be used as a means of identifying a recent IBV infection. Because IgG appeared to compete successfully with IgM for sites on the viral antigen, it was found necessary to separate IgM from IgG prior to testing in the ELISA.