In vitro and in vivo detection of infectious pancreatic necrosis virus in fish by enzyme-linked immunosorbent assay

Abstract

A double antibody enzyme-linked immunosorbent assay (ELISA) was used to detect infectious pancreatic necrosis virus (IPNV). The ELISA detected VR299 strain of IPNV at a dose of 10 to 20 ng of purified IPNV protein or 10(4) TCID50 in tissue culture fluid. Specificity of ELISA was demonstrated by an ELISA inhibition test. The ELISA did not detect infectious hematopoietic necrosis virus. Normal cell culture fluid and virus-non-inoculated rainbow trout (Salmo gairdneri Richardson) homogenate did not react in the test system. The IPNV was detected in rainbow trout fry inoculated with IPNV. Although infective virus titer in fish decreased rapidly 1 week after inoculation, IPNV antigen was detected by ELISA for 15 days. The IPNV antigen was detected in the fish tissue after inactivation of infective virus. The ELISA is a rapid and reliable method for the diagnosis of IPNV infection.