BETHESDA, Md. -- Health officials anxious to find the best way to protect America's blood supply from mad cow disease are outlining the possibilities before a federal advisory committee considering several different plans.
The Food and Drug Administration advisory group was considering proposals Thursday by the FDA and by organizations, such as the American Red Cross, that collect, process and distribute blood used in transfusions and in other medical procedures.
Officials said the committee will vote on recommendations to the FDA, which does not have to follow them, but generally does.
Experts are concerned that people who have traveled or lived in Europe, particularly Britain, may have eaten beef contaminated by bovine spongiform encephalopathy, or mad cow disease. Studies have shown that the disease can be transmitted to humans in meat and, years later, cause a brain disease called new variant Creutzfeldt-Jakob disease, or vCJD.
Although it has not been proven, health experts fear that people who have eaten contaminated beef might transmit the disease through donated blood.
The FDA now forbids blood donations from people who spent six months or more in Britain between 1980 and 1996. Britain was the center of an outbreak of mad cow disease and at least 91 people there developed vCJD, which rots holes in the brain.
Restrictions also cover those who have lived a total of 10 years in France or Portugal since 1980.
The Red Cross, which collects about half of the 13 million units of blood used annually in the United States, wants even tougher restrictions, forbidding donations from anyone who lived in Europe for any period of six months since 1980, or three months in the United Kingdom.
An FDA proposal would extend the restrictions to include donors who have lived five years or more in Europe from 1980 to the present, or who have spent a total of three months in the United Kingdom from 1980 through the end of 1996.
America's Blood Centers, a network of community blood centers, is calling for a ban on blood donations from people who have spent three months or more in the United Kingdom from 1980 to 1996, or people who have spent 10 years or more in France or Portugal.
Experts say the effect of the proposals would be to reduce the nation's blood supply. Estimates are that the Red Cross plan, for instance, would lead to a 9 percent decrease in available blood units while eliminating about 92 percent of the risk of collecting blood infected with vCJD.
The impact would be felt hardest in New York City. An FDA survey estimated that under some of the plans the blood supply in New York could be reduced by about 35 percent, some 190,000 units per year.
Although it has been proven that vCJD can be contracted from meat, there has been no proof that it can be transmitted through donated blood. The theoretical possibility, however, has prompted the FDA to re-examine blood safety frequently and revise restrictions on donors as needed.
Mad cow disease is caused by an abnormal protein, called a prion, which can cause changes in normal proteins and result in deep lesions in the brain. Mad cow disease has not been confirmed in U.S. cattle, nor has any patient been identified as having vCJD. There are American cases of Creutzfeldt-Jakob disease, but these cases have not been of a type linked to food.
On the Net:
FDA and mad cow disease: http://www.fda.gov/oc/opacom/hottopics/bse.html
American Red Cross: http://www.redcross.org
America's Blood Centers: http://www.americasblood.org