Article Text

Descriptive spatial analysis of scrapie-affected flocks in Great Britain between January 1993 and December 2002
  1. S. C. Tongue, BVSc, MSc, MRCVS1,
  2. D. U. Pfeiffer, DrMedVet, PhD, MACVSc, DipECVPH2 and
  3. J. W. Wilesmith, BVSc, HonMFPHM, DipECVPH, MRCVS3
  1. 1 Scrapie Epidemiology Group, Centre for Epidemiology and Risk Analysis, Veterinary Laboratories Agency — Weybridge, Woodham Lane, New Haw, Addlestone, Surrey KT15 3NB
  2. 2 Epidemiology Division, Department of Veterinary Clinical Sciences, Royal Veterinary College, Hawkshead Lane, North Mymms, Hatfield, Hertfordshire AL9 7TA
  3. 3 Animal Health and Welfare Directorate General, DEFRA, 1A Page Street, London SW1P 4PQ
  1. Professor Wilesmith is also at the Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, Keppel Street, London WC1E 7HT


The spatial distribution of sheep flocks in Great Britain with confirmed clinical scrapie between January 1993 and December 2002 inclusive was investigated by using kernel density estimation and a cluster scan test statistic. Six statistically significant clusters were identified: three were lower risk, and were centred on the north-western coast of Scotland, the north-western coast of Wales and the South Yorkshire/Pennine region; three were of higher risk, and were centred in the central south, North Yorkshire and north Cumbria. General knowledge and the results of previous epidemiological studies were used to generate biologically plausible hypotheses that might explain these findings. They included aspects of flock management and disease transmission, and factors associated with the identification of cases, including their detection, recognition and, in particular, reporting levels, as well as diagnosis and animal movements.

Statistics from

Request permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.