Canada Bans Blood Donations From People With History of CFS/ME

Canada Bans Blood Donations From People With History of Chronic Fatigue Syndrome

Canada's national blood service has announced that from next month it will ban blood donations from people with a medical history of chronic fatigue syndrome (ME) as a precautionary measure. It is the first country in the world to do so.

"Canadian Blood Services takes the safety of the blood supply very seriously" said Dana Devine , the agency's vice president of medical, scientific, and research affairs. "Until recently Canadian Blood Services has accepted blood donations from donors who report a history of [chronic fatigue syndrome] but are now well. Donors who are not well may not donate blood".

Dr Devine cited a report in Science last October (2009;326:585-9, doi:10.1126/science.1179052) suggesting a link between the syndrome and the presence of a retrovirus, the xenotropic leukaemia virus related virus (XMRV).

The study, which looked at peripheral blood mononuclear cells from patients with chronic fatigue syndrome, identified DNA from XMRV in 68 of 101 patients (67%) but in only 8 of 218 (3.7%) healthy control patients. Cell culture experiments showed that patient derived XMRV is infectious and that both cell associated and cell free transmission of the virus are possible.

Secondary viral infections were established in uninfected primary lympocytes and indicator cell lines after their exposure to activated peripheral blood mononuclear cells, B cells, T cells, or plasma derived from patients with the syndrome, prompting the researchers to suggest that XMRV may be a contributing factor i the pathogenesis of chronic fatigue syndrome.

Dr Devine explained " These researchers could show that the virus from patient blood samples was able to infect cell lines in the laboratory. What remains unknown was whether this virus is actually the cause of [chronic fatigue syndrome] in these patients.

"It was also unclear from this study whether there was actually live virus in healthy people as these researchers were only able to demonstrate a piece of the XMRV genome called "gag" but not other parts of the virus that one would expect to find if the virus was intact and capable of being infectious. So, important questions remained unanswered, particularly with respect to risk to the blood system.

"Given the lack of clarity around XMRV, we are changing the way we manage donors such that any donor who has a medical history of [the syndrome] will be indefinitely deferred from donating blood". She added that the agency preferred to err on the side of caution in a bid to guarantee the safety of blood supply.

"Until XMRV is better understood and more is known about the role the virus plays in [chronic fatigue] and related illnesses we will safeguard the blood supply through this deferral" Dr Devine said. "Once we understand more about this issue, we will revisit this decision to determine whether the indefinite deferral is still warranted".

Studies conducted in early 2010 in the United Kingdom and in the Netherlands were unable to confirm the findings of the Science study, she noted (BMJ 2010;340:c1033, doi:10.1136/bmj.c1033).

Health officials in the United States are also investigating the association between XMRV and chronic fatigue syndrome and its potential significance for the blood supply.

{Barbara Kermode-Scott, Calgary, Alberta}