It has recently become increasingly well recognized that parenteral administration of whole blood or blood products to susceptible individuals may be followed by the occurrence of a disease which is clinically indistinguishable from common acute infectious hepatitis.1During the latter part of 1944 a large and increasing number of cases of acute hepatitis were seen at a large army general hospital within the continental limits of the United States which serves primarily as a center for amputation and neurosurgical cases. During the six month period from Nov. 1, 1944 to April 30, 1945 a series of 108 cases of acute hepatitis came under the care of one of us (E. B. G.). Of these cases 103, or 95 per cent, occurred in men who had recently been wounded in action in either the European or the Pacific theater of operations. The fact that the high incidence of the disease