Red Cross sets tougher blood donor criteria

WASHINGTON (CNN) -- The American Red Cross is implementing tighter restrictions on who can donate blood, in an effort to keep the U.S. blood supply free of the human form of mad cow disease, CNN has learned.

Beginning in September, people who lived in the United Kingdom for an accumulated three months since 1980 cannot donate blood. Potential blood donors who lived in other European countries for an accumulated six months since 1980 are also excluded. Finally, anyone who received a blood transfusion in the United Kingdom will be restricted from donating blood.

To this date there is no scientific proof that variant Creutzfeldt-Jakob Disease (vCJD), the human form of mad cow disease, can be spread through blood.

However, there is no test for mad cow disease in animals or humans. Experts say it takes five to 15 years for symptoms to show up, so people may have the disease and not know it.

ALSO Red Cross wants tighter restrictions on blood donors     RESOURCES Find out more about donating blood American Red Cross America's Blood Centers

The new guidelines are meant to keep anyone who may have been exposed to the disease from donating blood.

The Red Cross handles approximately 50 percent of blood donations in the United States. The new restrictions will bar 4 to 9 percent of potential blood donors, or an estimated 900,000 people, from donating blood according to a Red Cross representative.

Last year nearly 4 million people in the United States donated blood, according to the Red Cross Web site.

The new Red Cross restrictions are tougher than those set by the Food and Drug Administration, which sets federal guidelines for blood donations in the United States.

According to current FDA guidelines, people who spent more than six months in the United Kingdom from 1980-1996 are banned from donating blood.

Earlier this year, an FDA advisory committee recommended that anyone who spent more than 10 years in Portugal, France and/or Ireland from 1980 to the present also be barred from donating blood, but the FDA has yet to make a final decision on these expanded restrictions.

The new Red Cross restrictions fall well within the FDA guidelines.