UK Blood Supply

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Headline: WSJ:`Mad Cow' Fear Leads U.K. To Destroy Donated Blood

Wire Service: DJ (Dow )

Date: Tue, Nov 24, 1998

By Steve Stecklow

Staff Reporter of The Wall Street Journal

LONDON - Two and a half years after the " mad-cow disease " scare hit the

United Kingdom, British beef is back. Domestic consumption has rebounded,

and the European Union this week voted to lift its ban on exports.

Scientists generally believe that, following the slaughter of 2.5 million

cattle and other precautions, people now can eat British beef without fear

of the brain disease that killed tens of thousands of British cattle and,

many scientists believe, was passed to 31 people as well. " It is now just a

matter of time before top-quality British beef is enjoyed across the world

once again, " says Ben Gill, head of the U.K.'s National Farmers Union.

But that doesn't mean the scare is over. It has taken a new turn. The

latest concern isn't about British beef, but British blood. Some scientists

now fear that the disease could be passed through transfusions of blood

from people who once ate infected beef, and as a result harbor the

infectious agent.

The risk remains hypothetical. Scientists aren't sure whether the disease

can be spread through blood at all. But new research suggests it is

possible, and there is no laboratory test to screen the blood.

So the British government, under criticism for having reacted too slowly

to the mad-cow problem in the past, is taking no chances this time. In an

unprecedented and controversial decision to reduce the risk of infection,

it has begun destroying nearly all the plasma - the liquid part of blood

that is used to make products for hemophiliacs, burn victims and others -

from all blood donations in Britain. It is replacing the plasma with

supplies from the U.S., where there have been no reported cases of the

disease.

In addition, the government has begun removing and destroying the white

blood cells. These are part of the immune system, and they are suspected of

playing a role in the disease's progress. By next year, both actions should

be fully in place.

" We're erring on the side of caution, " says Sue Cunningham, a spokeswoman

for Britain's National Blood Service.

In the U.S., some suggest the British are overreacting, especially in

their decision to destroy plasma. " This response is based on a theoretical

risk only, and therefore I feel it is a bit extreme, " says Davey,

chief medical officer of the American Red Cross. Brown, a senior

research scientist at the National Institutes of Health, calls the policy

" an archconservative position " that represents " ultimate caution, " although

he says he can't argue with it. " If you can afford to do it, that's fine, "

he says. " It costs a fortune. "

Indeed, the British actions are expected to cost $165 million a year-half

of the National Blood Service's budget - and increase the cost of blood

products. But Rawlins, who heads the government advisory board on

medicine safety that recommended destroying plasma, says the decision was

unanimous. " We fervently hope it's a waste of money, " he says. " Because if

it isn't, we're in real trouble. "

Much remains a mystery about " mad-cow " disease, which is formally called

bovine spongiform encephalopathy, or BSE. The fatal illness suffered by the

31 victims has been labeled " new-variant Creutzfeldt-Jakob disease " - after

another rare brain disorder in humans - and appears identical to BSE.

Scientists still don't know the origin of mad cow, which was first

confirmed in Britain in 1986. But they are convinced it spread among cattle

because diseased animals were recycled-infected parts were ground up and

processed into animal feed. To date, there have been more than 175,000

confirmed cases in British cattle, and much smaller numbers in 14 other

countries. There haven't been any in the U.S.

Researchers have demonstrated with experimental mice that the same

infectious agent that causes BSE-believed to be a rogue protein called a

prion-also causes the human disease. Yet there remains no definitive proof

that infected beef was the source of the outbreak in humans, although this

notion is now very widely accepted. " We can't do the obvious experiment,

which is to actually feed BSE brain material to a human, " notes Moira

Bruce, a biologist in Edinburgh who did the mouse experiments.

Still other critical questions remain unanswered: How much exposure to

the infectious agent does it take for a person to contract the disease? How

long does it take for symptoms to appear? Why has the disease targeted

mainly young people (the average age of victims was 29)? And, the greatest

mystery: How many people walking around today might be infected?

What is clear is that the disease is dreadful. After lying essentially

dormant for years, it suddenly attacks and decimates the brain. " There's no

cure, there's no treatment, there's nothing you can do, " says Dorothy

Churchill of Wiltshire in southwest England, whose son, , was the

first confirmed case. A fit young man who had passed tests to be a pilot in

the Royal Air Force, he suddenly grew depressed in 1994, suffered

hallucinations and soon couldn't bathe or eat. Within a year, he was dead

at the age of 19.

The concern about human blood grew last year following research conducted

in Britain and Switzerland. In London, a team led by Collinge at

Imperial College School of Medicine discovered traces of the disease in

victims' tonsils, a lymphatic organ where white blood cells known as B

lymphocytes circulate. The research also suggested that new-variant CJD

behaves differently from the classical form of Creutzfeldt-Jakob disease,

which isn't found in the tonsils (and has never been linked to

transfusions).

Meanwhile, a team in Zurich led by o Aguzzi conducted mouse

experiments that indicated B lymphocytes may play a role in transporting

the disease agent to the brain. The researchers found that mice with

defective B lymphocytes didn't contract scrapie - a related prion disease

seen in sheep-when injected with infected tissue in the abdominal cavity.

Other mice with normal B lymphocytes did develop the disease.

The findings prompted Britain's health department last year to establish

a policy to recall and destroy any plasma products made from blood

donations from the people diagnosed with new-variant CJD. That is no easy

task. Cases usually aren't confirmed until after death, and blood donations

may have been made years before. Users of blood products also often aren't

tracked. In fact, at least four of the 31 people who have died of the

disease were blood donors, and in two cases, their blood was used in

products given to patients.

An individual's blood may end up in thousands of products. To make plasma

products in quantity, manufacturers pool many blood donations - in Britain,

as many as 62,000.

Dr. Rawlins, the advisory-board chief, says the recall policy adopted

last year " meant that we were seriously going to interfere with the

availability of blood products generally. " So the next step, to import all

plasma used in pools, was logical, he says. The decision, made in May,

doesn't affect fresh-frozen plasma, which isn't pooled and is used in

life-threatening situations. It also doesn't affect red blood cells, which

are used in transfusions, or clotting agents called platelets, which are

used in cancer therapies.

Dr. Aguzzi, a professor at Zurich University, serves on another

scientific panel that advises the British government on new-variant CJD and

related diseases. After much debate, the panel recommended in June the

removal of white blood cells from all blood donated in Britain, a process

known as leukocyte reduction. The government accepted the advice in July.

" It was a difficult decision to take, and we still don't know whether it

was the correct one, " Dr. Aguzzi says. He supported leukocyte reduction

even though he agrees that his own research " has certainly not proven that

blood is infectious. " He notes that his experiments involved mice, not

people, and that the disease studied was scrapie, not BSE or new-variant

CJD.

" I would say this was rather indirect evidence, " he says, " On its own, it

certainly would not suffice to justify measures of public health. " In fact,

his latest research, to be published next week in the journal Nature

Medicine, shows that the role played by B lymphocytes in prion diseases

remains unclear.

Still, he believes the decision was prudent in view of the tonsil

research, plus recent findings of traces of the infectious agent in the

human appendix as well. He also notes that there are other advantages to

the removal of white blood cells, a practice that is already in use in

several countries, including France and Portugal, and is under

consideration by the U.S. Food and Drug Administration. Dr. Davey, of the

American Red Cross, explains that the process can reduce bad reactions to

transfusions, such as high fever, and eliminate the risk of transmitting

viral diseases.

In weighing their decisions, Dr. Aguzzi and other scientists say they are

particularly mindful of the early years of the AIDS epidemic, when

thousands of people who had transfusions became infected before

blood-screening tests existed. " The AIDS blood scandal was a catastrophe, "

he says, and with no screening test available for this disease, the

situation may be " not totally dissimilar. "

(END) DOW JONES NEWS 11-24-98

11:01 PM

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