If proven in further studies using animal and human blood, it could be an a more effective alternative to the current practice in the U.S. and in Britain of screening blood donors for possible contacts with people who are known to have vCJD.
"Blood-associated transmissible spongiform encephalopathy infectivity presents unique challenges to risk management absent from other blood-borne pathogens," the investigators wrote. "The low concentration of infectivity, although difficult to detect, has nevertheless been sufficient for efficient transfusion transmission of these fatal diseases. People with certain genotypes could harbor the infection in a transmissible but undetectable form for decades."
In the Dec. 8 issue of The Lancet, British researchers reported a third case of vCJD in an at-risk group who were given tainted blood transfusions. The patient was the first to be identified before death as having the disease. The 32-year-old man developed the disease after a red-cell transfusion donated by a person later determined to have vCJD.
Two other cases -- identified after death and reported two years ago -- were previously identified among 66 people who got blood transfusions from donors who subsequently developed vCJD, according to Stephen Wroe, M.D., of the National Prion Clinic at the National Hospital for Neurology and Neurosurgery in London.