Rapid detection of infectious pancreatic necrosis virus (IPNV) by the enzyme-linked immunosorbent assay (ELISA).

Abstract

The enzyme-linked immunosorbent assay (ELISA) was used to demonstrate the presence of infectious pancreatic necrosis virus (IPNV) antigen in cell cultures and in fish. Virus antigen could be detected in infected cell cultures before visible cytopathic effect (c.p.e.) was evident and cell cultures showing complete viral c.p.e. produced intense colour reactions. Virus antigen was detected in infected fry during and immediately after an epizootic, but although IPNV-carrier fish could be detected by the ELISA technique, the sensitivity of detection was not as great as that of isolation of the infectious virus in cell culture. The major IPNV serotypes, Sp, Ab and Vr, crossreacted at only a low level and it was shown that the ELISA technique could be used to serotype IPNV strains rapidly. None of 10 other fish pathogenic viruses reacted with plates sensitized for IPNV detection. The time taken to perform the technique was reduced to 1 h 35 min at room temperature and this still allowed the results to be readily assessed visually as antigen-positive or antigen-negative.