Title: Transfusion Medicine Epidemiology Review (TMER)
Funder: Department of Health (England)

Abstract: Background CJD is a rare disease. There is no evidence to suggest that sporadic CJD (sCJD) or familial CJD (fCJD) have been transmitted in humans by blood transfusion. The description of variant CJD (vCJD), linked to BSE in cattle, and the knowledge that the CJD agent can be transmitted by human growth hormone injection, dura mater and corneal transplant, gives impetus to attempt to establish whether the blood transfusion might be a means of transmission in certain circumstances. The possibility of wide-spread transmission of CJD in the event that any of the forms of CJD are transmissible by blood, and that such forms occur in epidemic proportions in the population, are potentially disastrous. The study is aimed at finding evidence of any such spread amongst cases of CJD known to the CJD Surveillance Unit. Aims The aim of the study is to use the CJD Surveillance Register and UK Blood Service records to see whether:- a) Patients with CJD may have given blood donations and, if so, whether any patient receiving that blood is also known to have CJD and b) Whether any patient with CJD has ever received a blood transfusion and, if so, whether any of the donors are known to have CJD. Plan of Investigation The study uses standard “lookback” methods by which the Blood Services routinely trace patients who received blood from a donor now known to be carrying an infection which can be transmitted by blood transfusion. Within the TMER, however, there is no attempt to contact either donors or patients identified through the study. The CJD Surveillance Register acts as the starting point for a search for evidence that CJD might have arisen in “pairs” of blood donors and the recipients of their blood. At the time that the study commenced, there was no such evidence in published literature, and no direct experimental evidence that CJD could be transmitted between humans by blood transfusion. Potential Impact The possibility of wide-spread transmission of CJD in the event of any former CJD being both transmissible by blood and present in epidemic proportions in the population is potentially disastrous. Policy Relevance Surgical instruments subsequently confirmed to have been used with patients incubating variant Creutzfeld-Jakob disease represent a valuable resource. A number of investigations into the detection of the infectious agent are ongoing and the availability of these instruments will provide an opportunity to test proposed procedures with clinically relevant materials. Safe recovery of these instruments will relieve a potential hospital infection risk and allow an archive suitable for the above purpose to be generated. Their availability via a single secure location will make subsequent investigation safer and more practical. On-site TSE containment facilities can be made available where appropriate, or where the investigating scientist has the necessary facilities, secure transport can be arranged and appropriate briefing provided. This will also assist in maintaining patient confidentiality and also in securing a higher degree of standardisation and control than would otherwise be possible. The outcome of tests performed on the instruments will, therefore, provide valuable information to the Department of Health for the assessment of infection risks, on the effectiveness or otherwise of specific cleaning/handling procedures and on the specificity and sensitivity of a variety of detection and decontamination methods. Surgical instruments subsequently confirmed to have been used with patients incubating variant Creutzfeld-Jakob disease represent a valuable resource. A number of investigations into the detection of the infectious agent are ongoing and the availability of these instruments will provide an opportunity to test proposed procedures with clinically relevant materials. Safe recovery of these instruments will relieve a potential hospital infection risk and allow an archive suitable for the above purpose to be generated. Their availability via a single secure location will make subsequent investigation safer and more practical. On-site TSE containment facilities can be made available where appropriate, or where the investigating scientist has the necessary facilities, secure transport can be arranged and appropriate briefing provided. This will also assist in maintaining patient confidentiality and also in securing a higher degree of standardisation and control than would otherwise be possible. The outcome of tests performed on the instruments will, therefore, provide valuable information to the Department of Health for the assessment of infection risks, on the effectiveness or otherwise of specific cleaning/handling procedures and on the specificity and sensitivity of a variety of detection and decontamination methods.


Research activity codes: 2.1 BIOLOGICAL AND ENDOGENOUS FACTORS;8.3 POLICY, ETHICS AND RESEARCH GOVERNANCE
Health categories: NEUROLOGICAL