THE BSE RISK: Delay gave infection chance to spread

The first case of BSE was discovered in 1985 but it was more than four years before the cattle products thought most likely to act as pathways for the disease were banned for human consumption.

That crucial period provided a crucial window for infection to pass from cattle to humans. Meanwhile, the number of cattle with BSE increased, one independent estimate putting the total in Britain between 1981 and 1988 at 675,000.

BSE was first officially diagnosed by the Central Veterinary Laboratory, a government agency which comes under the umbrella of the Ministry of Agriculture, Fisheries and Food (Maff) in November 1986. But it was not made public until the following year when tests began to see whether BSE could be transmitted to infected cattle's offspring and to other species.

In April 1988, the Government appointed a committee under Sir Richard Southwood to assess the significance of BSE. In June that year, the committee recommended that infected animals be destroyed, that milk from such animals be disposed of, and that BSE be made a notifiable disease, which meant farmers were required by law to report cases to Maff.

On 21 June 1988, BSE became a notifiable disease and on 18 July the feeding of cattle or sheep protein to other cattle or sheep was banned. It is believed that BSE resulted from cattle eating feed containing offal from sheep infected with scrapie.

The third measure resulting from the Southwood recommendations showed the Government's half-hearted commit- ment to tackling the problem - on 8 August, it announced that infected cattle should be slaughtered but that farmers would only get 50 per cent compensation. It was hardly an inducement to report cases of BSE and it was not until February 1990 that full compensation was introduced.

It took until December 1988 for the Government to implement Southwood's recommendation that milk from infected animals should be destroyed, and it was not until April 1989 that they acted on the suggestion that a research committee be set up to discover the full extent of the threat to animals and humans.

On 13 November 1989 - almost 18 months after concern was first expressed about the possible inclusion of cattle brains in foods such as meat pies - bovine offals such as brains, spinal cords, gut, tonsils, thymus and spleen were banned for human consumption. It was another three months before the measure was introduced in Scotland.

Offals were thought to be the most likely route for infection. But even this measure was incomplete as cattle up to six months old were exempted because it was thought that they represented less of a hazard.

Research has shown that BSE is transmissible to mice from the intestines of young cattle, but it was not until July 1994 that the ban was extended to cattle under six months old.