According to Louis Katz, people suffering from chronic fatigue syndrome (CFS) should not be donating blood until more is known about the retrovirus XMRV. Katz is executive vice-president of medical affairs at Mississippi Valley Regional Bllod Center in Davenport, Iowa and is also a member of the AABB task force.
"Last October, a paper in the journal Science linked XMRV — first discovered in 2006 — to CFS, which affects an estimated 17 million people worldwide. Since then, public health officials have been racing to learn more. Although it still isn’t yet known whether XMRV causes CFS or any other disease, there are concerns that the virus might be transmitted through blood donations."
Jennifer Garfinkel is a spokesperson for AABB, who stated that the FDA blood donation guidelines do not prohibit people suffering from chronic fatigue syndrome from donating blood. But she advised that until more is known about the science of the retrovirus XMRV it may be safer if people with CFS don't donate.
Australia, Canada and New Zealand now restrict people with chronic fatigue syndrome from donating blood.
http://blogs.wsj.com/health/2010/06/14/chronic-fatigue-sufferers-may-be-asked-to-avoid-donating-blood