hepatitis infections. this practice was not ended in the uk until 1984. for instance, no real efforts were made to prevent those who used intravenous drugs and with a four at a higher risk of hepatitis from donating blood. and for instance, the steps taken to keep donors who were more likely to be incubating aids out of the chain were late in starting. and when they finally began were inadequate. as for pool sizes the dangers of pulling plasma from many donors were established by the medical research council in 1944. the greater the number of donors to pull the greater the risk from it because one infected donation could contaminate the hopeful. in 1951 the textbook that was then the bible of blood transfusion said the use of large pool plasma has of course been