Medical

vCJD blood test developed

British scientists have developed the world's first reliable blood test for vCJD, which could reveal the true extent of the disease's prevalence in the population.

The breakthrough means large numbers of people could be sampled to give an accurate estimate of how many people are infected with the fatal brain disorder, which can remain dormant in humans for decades.

The new test is 100,000 times more sensitive than the current method, which involves extracting a small piece of tonsil tissue and analysing it.

Variant Creutzfeldt-Jakob Disease (vCJD) is the human equivalent of Bovine Spongiform Encephalopathy (BSE), which affects cattle.

 

Identified in the 1990s, the illness was traced to the consumption of beef products containing contaminated meat.

VCJD progressively causes the brain to become riddled with holes, leading to mental problems, loss of body function, and eventual death. There is no cure.

The Department of Health's working estimate is that 1 in 4,000 people - or about 15,000 individuals - are infected.

But Dr Graham Jackson, from the Medical Research Council Prion Unit, based at University College London, said the lack of a reliable test to date meant the real number could be far higher or lower.

He said: "This test could potentially go on to allow blood services to screen the population for vCJD infection, assess how many people in the UK are silent carriers and prevent onward transmission of the disease."

His team's research, based on 190 blood samples including 21 from individuals known to have vCJD, is published in The Lancet today (THUR).

Dr Jackson said the next step was to test the method in a population known to have almost no vCJD such as the US, to verify it threw up no "false positives".

Then at least 10,000 Britons would have to be sampled to get a reasonable estimate, he said.

Since the first cases were recorded in 1995 there have been 170 confirmed or suspected deaths from vCJD in the UK.