Letter: Test for CJD

Sir: "The only test that exists for BSE and CJD involves examining the brain tissue from victims" writes Kate Watson-Smyth ("Scientists takes step forward in battle against BSE", 6 November). Not so. A distinguished British virologist with an international reputation for the work he has been doing since 1970, both here and in the United States, on the "Scrapie agent" first offered the Ministry of Agriculture a urine test for BSE as long ago as 1993 and many times since. His offers have mysteriously always been refused.

At the request of relatives he has carried out his test on 15 humans who were suffering from possible CJD and in all 15 he found the test to be positive. Subsequent post-mortems confirmed that all 15 did have CJD. Had this urine test been carried out on cattle it could have identified the infected animals, thus restricting the cull and avoiding three farmers' suicides, together with the loss to the UK of an estimated pounds 4bn.

Why are we getting excited about a possible blood test which Zurich scientists may eventually elaborate when there is a urine test available already?

H C GRANT

London NW3