Both Stephen Dorrell, the Secretary of State for Health, and Douglas Hogg, the Agriculture Minister, insisted, however, that any risk of developing CJD from eating British beef was "extremely low" and said there were no plans to take it off school menus.
The news of the new cases came from Professor John Pattison, chairman of the expert advisory committee Seac, which spent last weekend deliberating on the risk to humans from bovine spongiform encepha-lopathy (BSE). It finally decided that there was no extra risk to children from the agent that causes BSE.
However, Professor Pattison revealed a widening gap between the increasing uncertainty within the committee about the dangers posed by BSE and the certainty expressed by ministers. Asked whether red meat was safe to eat, he said "There is no evidence in cases of BSE infection in muscle meat . . . but there are limits to the sensitivity of the tests, so in our calculation we can only say within limits of the tests."
Inquiries by the Independent have also established that the Department of Health and the Ministry of Agriculture, Fisheries and Food (Maff) still cannot answer the two key questions central to the current crisis.
Asked yesterday whether a single mouthful of infected beef could be enough to pass on the disease, or whether the effects were cumulative, both departments said they did not know - theough Maff said that a single gram of infected feed was sufficient in cows. Asked when the public could be sure that any risk of an epidemic of CJD caused by BSE-infected food was over, the answer was also that they did not know
The latest worries over a possible link between CJD and BSE have been raised by the Surveillance Unit in Edinburgh, which noted 10 cases in the past two years, striking people at an unusually young age - 27 years old on average, rather than 63, as in previous cases of CJD. Seac concluded that the best explanation for the 10 cases - from the total of 90 who developed CJD in Britain in the past two years - was exposure to BSE-infected materials before 1989. Some scientists had feared that this might mean that young people were especially susceptible to this new strain of CJD.
However, Mr Dorrell told the House of Commons that Seac had concluded that "infants and children are not likely to be more susceptible to [BSE] infection than are adults".
In the light of this, there was "clearly no reason for the Government to advise local education authorities to remove beef from school menus".