AABB is an international, not-for-profit association representing individuals and institutions involved in the field of transfusion medicine and cellular therapies. The association is committed to improving health by developing and delivering standards, accreditation and educational programs that focus on optimizing patient and donor care and safety. AABB membership consists of nearly 2,000 institutions and 8,000 individuals, including physicians, nurses, scientists, researchers, administrators, medical technologists and other health care providers. Members are located in more than 80 countries.
Thank you for the opportunity to participate in these discussions today by offering our perspective on the questions that have been posed to the committee. For more than one year AABB has been analyzing the findings of various research groups studying XMRV / MLV as they seek to understand whether infection by these agents causes human disease. In December 2009, AABB formed an interorganizational task force that includes representatives from the blood community, a patient advocacy representative, XMRV subject matter experts, and liaisons from government agencies. The task force was charged to review available data; make recommendations for action to assess and, if necessary, mitigate risk; and develop appropriate educational messages for donors, medical personnel and the public on the risk of XMRV transmission through blood. AABB has assembled a second task force that is focused on these same issues as they relate to cellular therapies.
As has been noted today AABB issued Association Bulletin #10-03 in June 2010 recommending that blood collectors, through the use of donor information materials available at the donation site, actively discourage potential donors who have been diagnosed by a physician with chronic fatigue syndrome (CFS), also known as chronic fatigue and immune dysfunction syndrome (CFIDS) or myalgic encephalomyelitis (ME), from donating blood. Educational materials were provided with the Association Bulletin. This proactive step was taken on the advice of the Task Force as an interim measure following the article in Science in October 2009 that reported an association between XMRV infection and CFS. At the time the Association Bulletin was published, the Task Force was also aware of the Lo study subsequently published in Proceedings of the National Academy of Sciences in September 2010, and considered these findings in making its recommendations. A policy of the active provision of educational materials to discourage potential blood donors from donating when they have particular illnesses or symptoms is a tool previously approved by FDA, which has been used successfully for many years by blood collectors. AABB believes this interim measure is appropriate and sufficient based on the available scientific evidence. The recommended process is, to our understanding, the most active approach to deferral of potential donors with CFS being used by major blood services around the world and preferable to introducing unvalidated screening questions. Implied in the AABB recommendation is that potential donors who identify themselves during the donor interview as having received a diagnosis of CFS from a physician would be deferred indefinitely. Information about the number, rate, and demographics of these donors who self identify is accumulating and at this point in time the numbers are not large.
AABB Standards already require that prospective donors be in good health and be free of cancer. In general, donors who present with a history of prostate cancer are deferred until they are disease free and no longer receiving therapy. These donor eligibility criteria for prostate cancer are supported by several epidemiologic studies that have shown no association between prostate cancer and a history of transfusion. Therefore, the Association Bulletin recommendations did not include a change in the deferral criteria for potential blood donors with a history of prostate cancer.
The Blood Products Advisory Committee has been asked to consider the issue of donor testing for MLV-related retroviruses even in the absence of confirmed disease causation. Absent evidence that these viruses have a causal role in any human disease it seems reasonable that the following criteria be met prior to the implementation of donor screening: 1) evidence of transfusion transmission of these viruses, 2) consistent evidence of association of these viruses with disease, and 3) development of validated assays for these agents that detect infected individuals but do not implicate non-infected individuals. The presence of a virus, and even transfusion transmission of an agent, is not, in and of itself a reason to implement donor deferral or screening. Since no causal association of XMRV with human disease has been demonstrated, a decision to introduce a blood donor screening assay, were one to become available, would appear to be premature. Many commensal viruses, for example Anellovirus species, are known to be transmitted by transfusion but despite extensive study have not been associated with disease. In the absence of direct evidence of causation, a decision to implement testing should be based on an assessment of recipient risk that includes the prevalence of the infection in the donor population, the transmission rate to recipients and the current best assessment of the risk of recipient harm, compared to currently accepted risks of transfusion.
Members of the blood transfusion community are concerned about the potential threat to the blood supply posed by XMRV / MLV and are actively involved in efforts to validate quality control panels and develop tests for the detection of MLV-related retroviruses. However we believe that current evidence does not support introducing any test methodology at this time. Furthermore, there are as yet no firm data to compare the efficacy of NAT versus antibody testing methods. AABB expresses its gratitude to the patients with CFS who are participating in these research projects and providing invaluable specimens for conducting the studies.
AABB remains committed to monitoring activity and supporting research associated with XMRV, taking steps as appropriate to ensure the safety of transfusion recipients and patients receiving cellular therapies, and participating in a dialogue with the FDA as necessary to further this goal.
* The AABB position does not necessarily reflect the official position of other organizations represented on the Interorganizational Task Force.