Cases of TSE disease found in sheep from passive surveillance have been recorded since 1993. The UK started active surveillance in sheep in January 2002.
In active surveillance, the number of sheep sampled in the testing programme has varied each year . It has included:
a sample of fallen sheep over 18 months of age.
a sample of healthy slaughtered sheep over 18 months of age.
Cases which have been identified from flocks in the Compulsory Scrapie Flock Scheme (CSFS) are shown separately.
The Animal and Plant Health Agency (APHA) attempt to trace all cases of scrapie back to their natal (birth) flock so that it can confirm disease on the appropriate premises and control measures can be applied. In some cases this can take time. Where a final decision has not been made on where to confirm disease, the case is included in the number of pending cases.