An international blood bank association is urging its members to discourage patients with chronic fatigue syndrome (CFS) from donating blood and blood components because of a potential risk of passing on the virus that is suspected of causing the elusive condition, even though the evidence for such a risk is not clear.
The international association, AABB, formerly known as the American Association of Blood Banks, released an Association Bulletin last Friday recommending that as an interim measure, until better scientific data is available, its member blood collectors should actively discourage potential donors diagnosed with CFS (also known as chronic fatigue and immune dysfunction syndrome, CFIDS, or myalgic encephalomyelitis, ME) because of the risk of trasfusion transmission of Xenotropic Murine Leukemia Virus-related Virus (XMRV).
The Association, whose membership includes nearly 2,000 institutions and 8,000 individuals in over 80 countries, urges member blood collecting organizations to make education materials freely available at its collection points that explain the reasons why individuals diagnosed with CFS by their physician should not donate blood. The materials include a poster and handout for potential donors.
In a statement explaining the reason for the recommendation to “discourage” donation by CFS patients, the Association pointed out that its members are required to follow federal regulations on whether donors are eligible to give blood or not, but at present “there are no specific regulations for deferral of individuals with diseases or syndromes that have been linked to XMRV”.
The AABB made the interim recommendation after its Interorganizational Task Force reviewed the current evidence on XMRV and its risk of transmission. The task force comprises representatives from patient advocacy groups, the blood community, experts on XMRV, and US government agencies, including the Centers for Disease Control and Prevention (CDC), the Food and Drug Administration (FDA), the Office of the Assistant Secretary for Health, and the National Institutes of Health (NIH).
The decision follows the publication in October 2009 of a paper in the journal Science that showed XMRV, a retrovirus previously linked to prostate cancer, was present in 67 per cent of 101 patients with CFS but only in 4 per cent of healthy controls. The paper raised concerns about the potential for XMRV in CFS, and is the first time a potential causative agent has been linked to the syndrome.
In the meantime, efforts to duplicate the results of the Science study and to develop reliable tests to detect the virus are still underway in several countries, so at the moment there is no independent confirmation of the findings. In fact, several European studies have failed to detect XMRV in the blood of CFS patients, underscoring the present difficulty of assessing the level of risk of transmission of XMRV by individuals with CFS.
Earlier this year, the Canadian Blood Services, Australian Red Cross and New Zealand Blood Services, announced they were indefinitely deferring all potential donors who volunteer they have a history of CFS when they undergo donor health screening.
The AABB interim recommendation was welcomed by the CFIDS Association of America who said in a statement that for years they have been explicitly advising patients with CFS against donating blood or organs, a policy they have recently reaffirmed following a board of directors meeting. At that meeting they reviewed a recommendation from the US Health and Human Services Chronic Fatigue Syndrome Advisory Committee (CFSAC), made in May 2010 that blood collectors should indefinitely defer donors with a history of or with currently active CFS by asking them a specific question about CFS during donor screening.
CFIDS Association president and CEO, Kimberly McCleary, who also sits on the AABB task force, told the media that:
“Our blood supply is dependent on donations from healthy volunteers.”
“Given the concerns for patient health on both sides of the donation equation, the AABB’s guidance to blood collection center staff will ensure the integrity of that supply is maintained while more research is conducted into CFS and XMRV,” she added.
McCleary also explained that a recent survey by CFIDS found that more than 6 per cent of patients diagnosed with CFS have given blood at least once following diagnosis, “underscoring the need for greater education and awareness”.
However, not all experts are happy with the announcement and say the decision is premature.
Jos van der Meer, a professor and chairman at the department of internal medicine of the Radboud University Nijmegen Medical Centre in Nijmegen, the Netherlands, who researches CFS, told Science Insider that it was “way too early” to make such a recommendation.
“They’re just spreading fear,” he said, “Let’s do some more serious science first”.
The CDC’s webpage on XMRV also stresses that the findings of the October 2009 study “and a potential link with prostate cancer and CFS must be scientifically and independently evaluated”.
“At present, although it is theoretically plausible that XMRV can be transmitted through blood transfusion, no such transmission event has been identified, and there is no known evidence of XMRV infection or XMRV-related illness in transfusion recipients,” says the CDC, confirming that several studies are currently underway to evaluate the risk of XMRV transmission through blood transfusion.
“If a link between XMRV and transfusion is established, action will be taken to reduce the risk,” they state.
Sources: AABB, Science Insider, CDC, CFIDS Association of America, MNT Archives.
Written by: Catharine Paddock, PhD