Blood Transmission

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Study Finds No Risk Of CJD Infection With Blood Transfusion

April 19, 1999

(NYT Syndicate) - The deadly brain condition Creutzfeldt-Jakob disease (CJD)

does not appear to be transmitted through blood or blood products from

infected donors, government researchers report.

" So far, " epidemiologist Abid Rahman said in an interview, " there's no

evidence of a link between infected blood and [CJD risk]. "

Rahman and his colleagues at the U.S. Department of Veterans Affairs (VA)

examined the cases of more than 1,500 veterans who, between 1991 and 1996,

received blood products from donors later found to have died from CJD. The

researchers found that as of 1996, none of the veterans had contracted CJD

from the contaminated blood.

While reassuring, these findings are not the final word on CJD risk and the

nation's blood supply. Since decades can pass between the time of exposure to

CJD and the first signs of the disease, Rahman noted, his team can conclude

only that for the time being, there is no established link.

" But, " he said, " we're doing whatever we can to monitor [the risk]. "

The VA researchers investigated only cases of classic CJD, not the recently

discovered CJD variant linked to bovine spongiform encephalopathy — more

commonly known as " mad cow " disease. Classic CJD, also a form of spongiform

encephalopathy, is an extremely rare disease that punches tiny holes in the

brain, causing loss of muscle control, personality changes, dementia and,

eventually, death.

Many researchers believe a virus-like protein called a prion transmits the

disease. There are documented cases in which transplant patients receiving

infected corneas or brain tissue have contracted CJD; natural human-growth

hormone is another potential transmission source. Infected blood, however,

has never been implicated in transmitting the disease.

Still, there has been concern over the possibility of blood serving as a CJD

vehicle, according to Rahman. " There's a very low probability, " he said,

noting that there is no blood test available to detect CJD in donors.

Rahman reported the VA study results Sunday at a meeting in San Francisco of

the Society for Healthcare Epidemiology of America.

The patients studied had been treated for various conditions with albumin,

plasma protein fraction or immune globulin — all products derived from donor

blood. Most were older than 60 at the time of treatment. Among the more than

500 patients who died during the study period, no death was attributed to

CJD, Rahman reported.

Classic CJD strikes mainly people older than 55. In addition to its

established transmission sources, the disease is in some cases passed on

within families. The federal Food and Drug Administration (FDA) currently

advises that blood banks question donors about family history of CJD and

whether they have ever received natural human-growth hormone or donated brain

tissue — cornea transplants are not considered a significant risk factor.

" There has never been a known transmission through blood, " said FDA

spokeswoman Lenore Gelb. " So it's just a theoretical risk. "

One expert called the VA study results reassuring. " There has been concern,

especially among hemophiliacs, who receive large amounts of donor blood

products, " said Dr. Celso Bianco, the medical director of the New York Blood

Center.

The reason CJD may not be transmissible through blood, Bianco explained, is

that the infectious agent — the prion — has been found only in brain matter,

and not blood. In animal experiments, he noted, CJD has been transmitted only

through transplants of contaminated brain matter.

For more information on CJD risk and the blood supply, visit the FDA Web site

at www.fda.gov