The test, involving a lumbar puncture to the spine, gives a positive or negative result within days and has been developed at the Laboratory of Central Nervous System Studies at the US National Institute of Health in Bethesda, Maryland.
"I am proscribed from saying anything at the moment, but the team hopes to publish its results within the next week or so. It is a very good, simple test and is something we just don't have at the moment," Dr Paul Brown, medical director of the US Public Health Service, said yesterday.
One of the problems with CJD is that the early symptoms are vague. Dr Brown, in a report in this week's British Medical Journal, says: "The ill-defined emotional and behavioural symptoms of the new variant of CJD will obviously open the floodgates to hundreds, if not thousands, of suspected cases of CJD over the next few years. It will be a matter of enormous practical importance to be able to screen real from imagined cases."
Speaking from Maryland, Dr Brown said yesterday that a research team had developed a test which involved an analysis of spinal fluid for a protein that is connected to the disease. "It will give neurologists the tool with which to test people and tell them that if they test negative, they are not going to die within six months. It is going to turn out be a very important tool because you can bet your money that a lot of people will think they have CJD." Details of the test are expected to be published in one of the medical journals within the next two weeks.
Dr Brown, one of the world's leading experts on CJD, has also warned against any premature mass slaughtering of cattle in Britain. "It must be emphasized that the link to cattle products is only a presumption," he wrote in the BMJ.
"How ironic, for example, if 11 million British cattle should be slaughtered in a pre-emptive strike to eliminate the risk of CJD, only to find belatedly that the true villains were pigs or chickens which were also fed the contaminated nutritional supplement, but were brought to market at such a young age that the disease had not had time to become manifest."
He said yesterday that transmission from pigs and poultry was a remote possibility. "I offered it as a theoretical possibility to broaden the focus, to get people to keep an open mind. I personally think that British beef now is as safe as any in the world. I am a beef man and I am very tempted to buy some of that Aberdeen Angus meat and ship it over here."Reuse content