Occurrences of red seabream iridoviral disease (RSIVD) in cultured mar
ine fishes were investigated. The infection was identified by using Gi
emsa staining method and/or indirect immunofluorescence test with a mo
noclonal antibody against red seabream iridovirus (RSIV). In total RSI
VD was found in 20 cultured marine fish species in 17 prefectures loca
ting south-western part of Japan from 1991 to 1995. Infected fishes in
clude 18 Perciformes, 1 Pleuronectiformes and I Tetraodontiformes.