vCJD Background Information

2002
Attention News Desk: Press Release (for immediate release)
MEDIA CONTACTS:
Michele Gassaway (650) 723-8237
mgassaway@stanford.edu
Michelle Brandt (650) 723-0272
mbrandt@stanford.edu

New guidelines regarding travel to the United Kingdom and Europe are a result of the Food and Drug Administrations (FDA) desire to further decrease the possibility that the agent that causes Bovine Spongiform Encephalopathy (BSE, or “Mad Cow Disease”) could enter the U.S. blood supply. Starting May 29, 2002, Stanford Blood Center will indefinitely defer individuals who have spent three cumulative months or more in the UK between 1980 and 1996. At the end of October, additional restrictions will be implemented.

BSE is a devastating neurologic disease of cattle caused by an infectious agent called a “prion.” BSE was epidemic in cattle in the United Kingdom between 1980 and 1996. In 1996, a new neurologic disease was recognized in people in the United Kingdom. It is now known that this new human disease, called variant CJD (vCJD), is caused by the same prion that causes BSE.

As of today, more than 100 cases of vCJD have been identified, mostly in the United Kingdom, but also in France and some other countries. New cases continue to be diagnosed in the United Kingdom and Europe. It is thought that the people who are now showing evidence of vCJD acquired their infections from exposure to beef products many years ago during the cattle epidemic. So far, there have been no cases of BSE among cattle in the United States.

There is no evidence that the agent that causes vCJD/BSE is transmissible from person to person by transfusion. However, it appears that people can have the prion infection in their bodies for many years without showing any symptoms. Blood agencies throughout the world are taking severe precautions to minimize the theoretical risk that someone who is unknowingly harboring the prion infection might transmit it to other people through donated blood.

Earlier FDA restrictions, implemented in February 2000, prohibited blood donations by individuals who had spent six months or more in the United Kingdom during the years of the BSE epidemic (between 1980 and 1996). The FDA estimates that this restriction reduced the theoretical risk of prion transmission by transfusion by about 87 percent. By further tightening donor restrictions, the FDA is hoping to eliminate about 90 percent of the theoretical transmission risk of vCJD. By phasing in the new donor restrictions, the FDA hopes to prevent life-threatening blood shortages that could result from a sudden loss of a large number of donors.

The following are FDA web sites with more information about vCJD:
http://www.fda.gov/cber/gdlns/cjdvcjd.pdf – FDA Guidance Document
http://www.fda.gov/cber/gdlns/cjdvcjdq%26a.htm – CJD Q&A

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