Evaluation of a rapid coagglutination (COA) test for the detection of infectious pancreatic necrosis virus (IPNV) in tissue samples of Atlantic salmon, Salmo salar L.

The field use of a staphylococcal coagglutination (COA) test for the detect ion of infectious pancreatic necrosis virus (IPNV) in tissue samples from A tlantic salmon, Salmo salar L., was evaluated. The COA test was compared wi th an immunohistochemical (IHC) method for the detection of clinical outbre aks of infectious pancreatic necrosis (IPN). The present paper describes th e evaluation of 320 COA test results performed at local fish health laborat ories in Norway from 1994 to 1996, and COA test results from two infection trials with IPNV. The agreement between the COA test and the IHC was very g ood. The agreement beyond chance, measured as kappa values, was 0.74 in ind ividuals and 0.90 in pooled samples. Thus, the COA test was suited for the detection of outbreaks of IPN. Covert infections with IPNV remained undetec ted by the COA test. The minimum IPNV titre needed to obtain a positive COA test was approximate to 10(5) TCID50 mL(-1).