The UK has a comprehensive surveillance programme in place to monitor the level of BSE over time and check on the continued effectiveness of our BSE controls. It was the effectiveness of these controls that recently identified a case in Scotland. Defra officials have engaged closely with Scottish counterparts on this matter, as they do regularly on animal disease issues more broadly with officials from all UK administrations under the Animal Health and Welfare Framework.

The measures to be followed in the event of suspicion of BSE are set out in UK legislation, and the Animal and Plant Health Agency (AHPA) are well prepared to carry out the necessary actions. In the rare event that BSE is suspected, whole farm movement restrictions are applied by APHA who then trace cohorts (animals that shared feed with the affected animal during its first year of life) and any of its offspring born in the last two years.

In the event of the suspect case testing positive for BSE, its cohorts and offspring are then humanely culled, samples are taken from the brain stem for testing and the carcases are then destroyed, with the owners of the culled animals receiving compensation. While it not believed that BSE can be transmitted by mother to offspring during pregnancy ('vertical transmission') these animals are culled, along with cohorts, on a precautionary basis.

The APHA also carry out a rolling national feed audit which inspects and takes samples at various stages of the animal feed chain. This includes checks for prohibited processed animal proteins in samples of feeding stuffs intended for farmed animals. If feed is non-compliant, APHA inspectors look at the cause of contamination and make a decision based on the risk. Depending on the severity, feed may have to be removed from the market, and cattle exposed to it may be restricted or killed.

We remain vigilant to the threat posed by BSE and have a comprehensive surveillance programme in place to monitor the level of BSE over time and check on the continued effectiveness of our BSE controls. More detail on this is set out in Defra’s latest TSEs annual report here:

https://www.gov.uk/government/publications/monitoring-programme-for-tses-annual-report-2021-and-2022.

Classical bovine spongiform encephalopathy (BSE) was first diagnosed in the United Kingdom in 1986. Scientific opinion is that classical BSE was caused by feeding feedstuffs to cattle that were contaminated with a transmissible spongiform encephalopathy (TSE) agent due to the inclusion of meat and bone meal. Scientific research has not identified any other definite vector of transmission and found no other potential causes, such as exposure to organophosphates. There is no evidence that it ‘spreads’ from animal to animal or between holdings.

As a result of this scientific opinion, a ban on prohibiting the sale, supply and use of feeding stuff incorporating animal protein for feeding to ruminants was put in place in the UK in 1988. Following further scientific advice, in 1996 the ban was extended to prohibit the feeding of mammalian meat and bone meal, or any feeding stuff containing it, to any farmed animals.

From a peak of over 37,000 cases in 1992 in the UK, there have been only 4 cases of the disease confirmed since 2014. This supports the hypothesis that classical BSE is a food-borne disease introduced by the inclusion of animal protein in feed, and that our BSE controls are working. It is still unknown which TSE agent caused the BSE epidemic (e.g. a scrapie agent from sheep or goats or an agent previously unknown in the cattle population that was recycled). Various transmission studies undertaken in GB and other countries failed to reproduce a BSE-like disease with TSE agents isolated from sheep or cattle other than classical BSE.