Thousands of patients face increased risk of vCJD

Six thousand patients have been warned they could be at risk of developing the deadly brain condition Creutzfeldt-Jakob disease through their treatment with blood products.

Six thousand patients have been warned they could be at risk of developing the deadly brain condition Creutzfeldt-Jakob disease through their treatment with blood products.

Letters were being sent to about 6,000 people this week with haemophilia and other bleeding disorders, plus a few dozen others with rarer conditions, who may have received contaminated blood plasma.

Sir Liam Donaldson, the Government's chief medical officer, who announced details of the alert yesterday, said the health department was taking a "highly precautionary approach" to maximise protection of the public.

The patients are at risk from the variant form of CJD linked with the consumption of BSE-infected beef, which may be passed on through blood. "[These] patients need to know they are at a small increased risk of developing vCJD [compared with] the rest of the population who ate beef during the 1980s and 1990s. This information will enable these people and their doctors to take the necessary steps to minimise the risk of onward transmission of vCJD," Sir Liam said.

The alert was sparked by the discovery of two cases of vCJD in the past six months in people who may have contracted it through blood transfusions. A review of blood transfusion records showed 15 people in England and two in Scotland received whole blood from donors who went on to develop vCJD and they were warned of their risk earlier this year.

At the same time, ministers announced a ban on people who had received a blood transfusion since 1980 from giving blood in the future.

Now plasma taken from these same blood donors has also been traced. It was used in the manufacture of 200 batches of blood products, each made from thousands of donations, for the treatment of people with haemophilia and related disorders.

In all, nine blood donors who went on to develop vCJD were identified who made 23 donations used in the manufacture of the blood products.

Professor Noel Gill of the Health Protection Agency said "less than a quarter" of the 200 affected batches of blood products carried a "significant risk" because of the degree of dilution and processing involved.

Professor Don Jeffries, chairman of the CJD Incidents Panel, said the dilution and processing to which blood products were subject meant the risk associated with them was "several orders of magnitude lower" than that to the recipients of whole blood. But it was important that their doctors and dentists were alerted in case they required surgery in the future which could result in the infection being transmitted to further patients through contaminated instruments.

"There is a general risk from exposure to vCJD and we want to avoid increasing it. [But] we don't want to cause undue alarm and damage the blood service or cause people to shy away from having surgery," Professor Jeffries said.

No transmission of vCJD via surgical instruments or the use of blood products has yet been recorded.