Those of us who have a decades-long involvement in the field of haemotherapy can confirm that the improved safety in industrially manufactured plasma derivatives has been one of the most significant achievements1. Penetration of the blood supply by infectious agents transmissible by blood had severe consequences on those patients who depend on regular treatment with concentrates of the proteins they lacked, particularly people with haemophilia requiring coagulation factors and immunodeficiency patients treated with immunoglobulins. Equally tragically, occasional transmissions also occurred in other groups, including women given prophylaxis treatment with anti-Rh immunoglobulin manufactured from plasma contaminated with hepatitis C virus (HCV). Before the development of adequate manufacturing processes specifically designed to eliminate infectious agents, the risk to the patient groups exposed to pooled plasma derivatives far outweighed the risk of recipients of labile blood components. Even with the advent of sensitive screening tests for viruses such as human immunodeficiency virus (HIV) and the hepatitis B (HBV) and C (HCV) viruses, the prevalence of these agents in conditions such as haemophilia approached 100%, with the devastating effects noted above, while the prevalence in the patient community receiving labile component transfusions for mainstream medical and surgical purposes approached 5–15%, depending on the epidemiology of the agents in the geographical area under study. At the same time, chronically transfused patients also suffered a high level of infection with blood-borne viruses2. Until the introduction of NAT testing for these agents, the large size of the manufacturing pool used for fractionation invariably included donations which were infective because they had been collected in the serologically silent window period3. In the absence of viral inactivation, this led to continued infection in patients until as late as 1990.
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