Surveillance of salmonid viruses especially targeting infectious salmon anemia virus in Japan

Infectious salmon anemia (ISA) is a virus disease of Atlantic salmon Salmo salar in Europe and the Americas, but it has not been isolated in Far East Asia. In this study, we conducted virus isolation with ASK and ASE cells targeting ISA virus (ISAV) from a total of 5,967 fish belonging to eight salmonid species in Japan from 2005 to 2007. ISAV was not isolated from any fish examined but infectious hematopoietic necrosis virus was isolated from 116 fish belonging to three species, while infectious pancreatic necrosis virus was found in 14 fish from three species. It was considered that Japan is still free from ISAV.