Viral infection associated with mortality in the oyster Crassostrea gigas Thunberg]

Virus particles and their morphogenesis have been observed in the cytoplasm of connective cells in the Japanese Oyster Crassostrea gigas. This virus seems to be similar to those described in the Portuguese Oyster Crassostrea angulata when high rates of mortality were recorded in 1970-1973 and those found in gill disease of this species.