Summary The fate of virus contaminants in shellfish was investigated by using the Northern Quahaug and a strain of type I polio virus as working models. It was shown that process of viral contamination in quahaugs was a dynamic one. Highest level of contamination was attained within a matter of hours followed by plateauing so long as viral level was maintained in surrounding seawater. Among all organs examined, digestive diverticulum, including stomach and hemolymph were found to harbor majority of contaminants. Further study indicated that viruses contained in these systems most likely did not penetrate into or adsorb chemically onto any type of cells. Implications of these findings have been discussed.