VIRAL DISEASES IN CULTURED MARINE FISH IN JAPAN

In Japan, mass mortalities of cultured fish due to infections diseases have been often reported. Among the pathogens, viruses are the most d evastating infectious agents that afflict fish. This paper reviews the major viral diseases of cultured marine fish in Japan. The major dise ases caused by DNA viruses include viral epidermal hyperplasia in flou nder and herpesviral disease in coho salmon, both caused by a hepesvir uses and lymphocystis disease and another iridoviral disease in red se a bream and other marine fishes. The major diseases caused by RNA viru ses are viral ascites (VA), viral deformity (VD) in yellowtail, both c aused by a birnavirus (YAV or VDV), erythrocytic inclusion body syndro me (EIBS) in coho salmon, a rhabdoviral disease in flounder and viral nervous necrosis (VNN) in striped jack and several other fishes by a n odavirus. The causative virus of Kuchijirosho in tiger puffer has not been classified.