The importance of applying confirmatory tests to detect infectious salmon anaemia virus (ISAV) in environmental samples by RT-PCR

When analysing seawater samples for ISAV by RT-PCR, a non-specific PCR product approximately the size expected for ISAV was obtained. DNA sequence analysis and southern hybridisation established it was not ISAV. A confirmatory test should be used with RT-PCR for ISAV detection in environmental samples to avoid misinterpretation of results.