Jj. Dewit et al., DETECTION OF SPECIFIC IGM ANTIBODIES TO INFECTIOUS-BRONCHITIS-VIRUS BY AN ANTIBODY-CAPTURE ELISA, Avian pathology, 27(2), 1998, pp. 155-160
The results of a new antibody-capture ELISA (alpha-IgM-IBV ELISA), spe
cific for IgM directed against Infectious Bronchitis Virus (IBV) show
that this assay is a useful tool for diagnosing IBV infections, The da
ta include individual results of the alpha-IgM-IBV ELISA in sequential
SPF chicken sera after vaccination with H120 and challenge with M41,
the specificity is based on results of 499 SPF sera, and the sensitivi
ty on sera from experimentally vaccinated and challenged birds. Also r
eported are ELISA results on 168 field sera originating from seven bro
iler flocks (24 samples per flock) collected during the acute phase of
an IBV infection. The alpha-IBV-IgM ELISA results obtained with field
sera from broiler flocks infected by Massachusetts, D207, D212 or an
unidentified serotype of IBV indicated that the ELISA, in which only M
41-strain was used as antigen, was able to detect IgM responses to IBV
serotypes other than Massachusetts. The specificity of the alpha-IBV-
IgM ELISA was 99%, the sensitivity based on the experimental vaccinati
on was 83 to 100%, depending on the day post vaccination. The sensitiv
ity, based on the experimental challenge, was 83%, while the sensitivi
ty, based on 168 field sera, was 93.5%, The IgM responses were rapid a
nd transient and therefore indicative for acute IBV infections.