Expert calls for blood donation ban to curb CJD

Brian McClelland, a consultant with the Scottish National Blood Transfusion Service, said the unknown risk of contamination meant it would be safer to introduce a ban on up to 42,000 donors.

Such a move would reduce stocks of blood - which are already in short supply - by as much as 15%.

It was revealed last week that a donor had died of CJD and that one of the people who had received their blood had also been killed by the disease. The case provided the strongest evidence yet that CJD can be transmitted by blood.

Malcolm Chisholm, the Scottish health minister, said he was considering a ban on donation recipients giving blood but McClelland suggested he should act now.

He told Scotland on Sunday: "My personal view is that it is probably something we should do, although we’d need to support it with considerably increased efforts in public relations and by encouraging people to give blood.

"There is a theoretical risk of recycling infections and quite a lot of good science to back up that concern.

"The worry is that could make a big dent in the availability of blood for people who really need it."

There is no proof that the blood recipient who died from CJD was infected by the CJD blood donor but experts doubt it was a tragic coincidence.

McClelland said: "I would say this is pretty unlikely to be a chance event. If you were a betting man you’d probably say this is a case of x being caused by y. I think this is giving us a fairly strong hint that transmission can occur."

Last night the British Medical Association in Scotland gave cautious backing to a ban. "It seems a reasonable precaution although the risk is small," a spokeswoman said.

About 280,000 Scots are currently on the transfusion service’s books as "active donors", of whom about 190,000 donate in the course of a year, providing 245,840 units of blood in 2002-2003.

It is not known exactly how many of them have had a transfusion in the past, but the figure is thought to be up to 15%, representing about 42,000 people.

Studies by the STBS and the UK’s National Blood Service estimate a ban would reduce total donations by between 3% and 15%. McClelland said he thought the figure could be about 5%.

The amount would vary according to the exact number of donors involved, and the type of ban. It could either have no time limit or apply to transfusions received after about 1980, by which time the first CJD infective agents may have been in the food chain.

The blood service would also have to decide how rigorously, if at all, it checked records to make sure donors who had previously received transfusions did not slip through the net.

One problem is that many people do not know they have been given blood in the past because it happened while they were under general anaesthetic.

A road accident victim can require up to 40 units of blood, while seriously ill patients, such as cancer and leukaemia sufferers, need up to 100 units during their treatment.

Phil Hanlon, professor of public health at Glasgow University, said there was a danger of over-reaction to a risk which "must be tiny".

"I guess the precautionary principle is being applied here. But you don’t necessarily take precautions against every imaginable risk," he said.

Hanlon also said the controversy over Scottish haemophiliacs who were given contaminated blood products could be influencing decision-making.

"I do wonder if that colours judgement," he said.

A spokeswoman for the Scottish Executive said: "We have asked the national blood transfusion service to look at this and to do so quickly but we have not set a time scale."

The entire problem could be avoided if there was a reliable way of screening donated blood for the CJD infective agent, a rogue protein known as a prion. But no such test yet exists.

In the meantime, Scottish doctors are likely to be reminded to minimise their use of transfusions. That advice had already been given as a precautionary measure before last week’s announcement of a possible CJD link between a transfused patient and a blood donor. It is now likely to be drummed home even more firmly.

Some patients are still given blood when that could arguably be avoided, as in "pick-me-up" transfusions for elderly people in hospital. It is increasingly felt by blood experts that such practices must end.

Last week health secretary John Reid told MPs of an incident in which a patient died after receiving blood years earlier from a donor who contracted CJD.

The case is the first report from anywhere in the world of the possible transmission of the disease via blood transfusions.

The donor showed no signs of illness at the time he gave blood in March 1996.

Soon afterwards, the donated blood was transfused into a patient who underwent surgery for a serious illness.

Three years later the donor developed variant CJD and died. The recipient of the blood died this autumn.

A total of 17 people in the UK, including two Scots, are known to have been given blood from a donor who later died from CJD.

Thousands more treated with blood plasma products could face a much smaller risk of infection.

In October, the blood service in Scotland warned that a blood shortage could mean planned operations might have to be cancelled within two weeks if more first-time donors did not come forward.

A crisis was averted by a public appeal which was answered by 6,500 people.

As of December 1 this year there had been a cumulative total of 143 cases of variant CJD in Britain.