Nobody can say they were not warned!
In 1958, there was an early warning about collecting blood from prisons from a respected international source. Dr. J. Garrott Allen discovered what he referred to as the "prison effect" after conducting a survey in the Chicago area. He discovered a high incidence of hepatitis infection in prison blood.
Throughout the 1960s the development of clotting factors derived from human blood progressed. In the mid to late 60's the discovery was made that Factor IX, Factor VIII concentrate and cryoprecipitate could be produced by pooling large quantities of plasma and these products came into general use for the treatment of various bleeding disorders.
Throughout this time, cases of hepatitis were emerging in haemophiliacs. Although more and more evidence on the risk of infection from prison blood was reported, the warnings were ignored and blood donor sessions in prisons continued in both the US and the UK.