BSE is, as we all know, a disease characterised by a long incubation period and progressive loss of nervous function, and is ultimately fatal. It was first diagnosed in November 1986 in England. The British government waited for nearly two years before appointing an independent expert working group under Prof Southwood. The Southwood Committee concluded that BSE was "most unlikely to have any implications for human health". This view was shared by the vast majority of veterinary and medical scientists until the emergence of the new variant CJD cluster in young adults and the subsequent announcement in the Commons in March of last year.

Enormous amounts of time, effort and money have been invested in BSE research from 1988 onwards. Various Acts and Orders have been introduced both in Britain and Ireland since BSE became a notifiable disease in June of that year. The principal concern for the researchers was to determine what animal tissues were infectious and to exclude these from the human food chain.

Infectivity was shown to exist in cattle brains, spinal cords, eyes and small intestines. These are now regarded as Specified Risk Materials (SRM) and are removed at veterinary inspection after slaughter. The British authorities introduced a ban on feeding ruminant meat and bone meal back to ruminants in 1988. The Government followed suit. In 1989, importation of animals from the UK to Ireland was banned. The Government, however, also went one step further than its counterparts in Britain by slaughtering the entire herd when a BSE case was confirmed.

However, in 1996 animals over 30 months of age were excluded from the food chain in Britain. Due to the very low prevalence of the disease in this country this policy was not adopted here. In addition Britain excluded meat and bone meal from all livestock rations (pig and poultry) in 1996, a decision which was not taken by the Irish authorities.

Since 1993, the incidence of BSE has declined by 90 per cent in Britain to a figure of 300 cases per week. Since the first case was diagnosed in Ireland in 1989 some 258 cases have been diagnosed in total. The total for November 1997 is four.

Last week the Spongiform Encephalopathy Advisory Committee (SEAC) in Britain released research findings that showed that infectivity could be detected in two new tissues, dorsal root ganglia (DRG) and bone marrow. These trials were carried out in calves given large doses of BSE at four months of age.

Using a series of pessimistic assumptions, the British committee concluded that three cattle out of a total kill of 2.5 million in 1998 might carry DRG infection. The DRG is a pea-sized, very inaccessible, body encased in a bony canal in the backbone.

The chances of acquiring nvCJD from meat on the bone were determined at one in 600 million. For infectious bone marrow to gain access to the food chain it would be necessary for an animal displaying clinical symptoms for three months to be accepted for slaughter. SEAC merely advised that the results of its research be made public. The British government, ever fearful of a public inquiry, took a very cautious option and instituted a ban on meat on the bone.

In response, the Minister for Health and Children, Mr Cowen, sought the advice of his own BSE/ CJD Advisory Group. On foot of this advice and with memories still fresh of the hepatitis C debacle he took an extremely cautious approach and advised for bone in meat to be removed from sale.

In doing so he may well have further undermined public confidence in Irish beef and placed beleaguered Irish producers closer to economic ruin. The scientific advice on which he based his decision is still unclear; perhaps he believed that there was no political alternative.

The Food Safety Authority of Ireland is at an embryonic stage. I hope the knowledge and extensive practical experience of the board will not be inhibited by political whim. A sense of balance must be preserved in dealing with issues of public health, the degree of risk assessed and resources directed to areas of primary importance.

Diarmuid Dooge is chairman of the Veterinary Certified Food Assurance Board, representing four Irish veterinary organisations