Thousands In Britain May Have Been Exposed To Mad Cow Disease: Officials

LONDON (AFP) - Letters went out to 6,000 patients in Britain who may have been exposed to variant Creutzfeldt-Jakob Disease (vCJD), the human form of mad cow disease, through blood plasma products, officials said.
The letters would explain the situation and set out ways to help minimise the risk of passing on the brain-wasting disease, the Department of Health said in a statement.
Health Secretary John Reid said it was a precautionary measure and that the risk of any of these patients developing vCJD was very small.
In December 2003, Reid announced the first case of a person dying after possibly contracting vCJD through a blood transfusion. That led to a ban on blood donations by people who have received a blood transfusion since January 1980.
In July it emerged that another patient who had received donated blood was found to be carrying the vCJD agent, although the person subsequently died of unrelated causes.
A risk assessment was ordered to look at blood plasma products derived from donated blood and used in products such as clotting agents to treat haemophilia and other bleeding disorders.
In May government-funded scientists estimated 3,800 people in Britain could be harbouring the human form of mad cow disease without knowing it.
The researchers examined 12,674 stored appendix and tonsil samples and identified three bearing signs of the agent that causes vCJD. Extrapolating their findings to Britain's entire population of 60 million, they estimated that about 3,800 people would test positive for the illness.
Three months later, in August, scientists from the CJD Surveillance Unit in Edinburgh said genetic research had shown many people could be carrying vCJD without realising it and could therefore potentially infect others via blood transfusions.
According to health ministry figures, 141 people are known to have died in Britain from vCJD, a spongy deterioration of the brain causing personality change, loss of body function, and eventually death.
Cases of the disease peaked in 2000, when 28 deaths were reported. Since then the trend has been generally downward, with 17 cases in 2002 and 18 last year.