MAD COWS AND ENGLISHMEN

FOR YEARS BRITISH GOVERNMENT OFFIcials have repeated the message: The "mad-cow disease" that has killed thousands of British cattle over the past decade represents no danger to humans. Just last December Prime Minister John Major insisted that there was "no scientific evidence" that the fatal brain infection, called bovine spongiform encephalopathy (BSE), could be transmitted through beef products.

The British public was thus doubly stunned last week when a government-appointed scientific commission indicated just the opposite. The commission had discovered a new strain of a deadly disorder called Creutzfeldt-Jakob disease and suggested that the likely cause for its spread was BSE. The announcement sent a wave of alarm across Europe. By week's end all but two European Union countries had banned British beef, and nations as far away as New Zealand and Singapore had done the same, cutting off trade that earns Britain $780 million a year. The U.S. has not permitted the import of British beef since 1989, when questions about its safety were first raised.

Even as he reported the new findings, British Health Minister Stephen Dorrell insisted that any danger from eating beef was minuscule. Officials point out that the number of infected cows is down from 36,000 in 1992 to 14,000 in 1995 because contaminated feedstuffs have been banned.

Since its first appearance in Britain in 1985, mad-cow disease has killed more than 150,000 head of cattle. Some scientists have maintained for years that BSE could cause Creutzfeldt-Jakob disease, which generally affects older people, causing symptoms similar to Alzheimer's. Last week's announcement was made by the National Creutzfeldt-Jakob Disease Surveillance Unit, in Edinburgh. Press reports identified 10 victims of Creutzfeldt-Jakob, all under the age of 42. They most likely contracted the disease through contact with BSE. Eight of them have died, and the remaining two are gravely ill. All 10 are believed to have come in contact with the virus before 1989, the year the government banned the use of nervous tissue and offal for animal or human consumption.

The 10 victims may be just the first ones. John Pattison, the microbiologist who headed the government commission, said last week that since Creutzfeldt-Jakob disease has an incubation period as long as 15 years, "there could be thousands more cases." Asked whether Britain might face an AIDS-like epidemic, he answered, "I cannot deny that's a possibility."

Though Pattison added that current beef eaters run little risk, the news cast a pall over Britain's traditional eating habits. Butchers said last week there was little call for beef cuts. At the Strand branch of Angus Steak Houses Ltd., in central London, the management was offering a special: just $10 for a sirloin steak with French fries and mushrooms. During a busy Friday lunch hour, the offer had few takers.

--By Michael S. Serrill. Reported by Michael Brunton/London