Risk of transmission of Creutzfeldt-Jakob disease by transfusion of blood, plasma, and plasma derivatives

Studies in experimental animals and case-reports of transmission of Creutzfeldt-Jakob Disease (CJD) by blood transfusion or by albumin products have raised the possibility that CJD may be transmitted by transfusion. The risk of transmission of CJD by transfusion remains theoretical, since no confirmed case of CJD has ever been causally attributed to the receipt of a blood transfusion, no confirmed case of CJD has developed in recipients of clotting factor concentrates, and no cluster of CJD cases has been reported following the administration of a pooled plasma derivative to which a donor who subsequently developed CJD had contributed. However, based on a review of the hitherto available data, it is impossible to conclude at this time that CJD is not transmitted by blood or plasma transfusion or by the administration of pooled plasma derivatives. This review discusses the findings of the animal experiments and the human studies that investigated the potential for transmission of CJD among humans by transfusion, and explains the statistical difficulties associated with proving the negative hypothesis that CJD is not transmitted by transfusion.