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Observations on the incidence of herds with non-visible lesioned tuberculin test reactors in south-west England

Published online by Cambridge University Press:  19 October 2009

J. W. Wilesmith
Affiliation:
Epidemiology Unit Central Veterinary Laboratory New Haw Weybridge Surrey KT15 3NB
D. R. Williams
Affiliation:
MAFF Regional Office, Burghill Road, Weslbury-on-Trym, Bristol BS10 6NJ
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Summary

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The herd incidence of confirmed Mycobacterium bovis infection in cattle in the south-west of England has been approximately ten times that of the remainder of England and Wales; this greater incidence has been attributed to infection from badgers. The incidence of herds with only non-visible lesioned tuberculin test reactors, from which M. bovis was not isolated, has also remained higherin the south-west region.

The incidences of these latter unconfirmed incidents were compared in parishes in the south-west region in which M. bovis in cattle had been confirmed, and those where M. bovis had not been confirmed, for the period 1979–83. This analysis was carried out both for those parishes in which herds had been subjected to annual tuberculin testing and for those subjected to biennial tuberculin testing. The incidence of unconfirmed incidents was significantly higher in parishes in which confirmedincidents had occurred, and this difference was found in both the annual and biennially tested parishes. The relative risks for the incidence of unconfirmed incidents in annually and biennially tested parishes were 1*89 and 2–56, respectively. The incidence of unconfirmed incidents in biennially tested parishes was lower than in annually tested parishes.

The incidence of non-specific tuberculin test reactor herds was estimated from tuberculin test results in the eastern region of England during a period when tuberculosis was not confirmed in cattle. A comparison of this incidence and that of unconfirmed incidents in the south-west region suggests that approximately 70% of the unconfirmed incidents in the south-west were related to exposure to M. bovis.

The results of the analyses indicate that unconfirmed incidents cannot be completely ignored in epidemiological analyses and studies of bovine tuberculosis in the problem areas of the south-west region of England.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1987

References

REFERENCES

Corner, L. A. (1981). The duration of the response of cattle to inoculation with atypical mycobacteria. Australian Veterinary Journal 57, 216219.CrossRefGoogle ScholarPubMed
Crawford, A. B. (1936). Tuberculin reactions in cattle showing no visible tuberculous lesions on post mortem. Journal of the American Veterinary Medical Association 89. 562583.Google Scholar
Evans, H. T. J. & Thompson, H. V. (1981). Bovine tuberculosis in Great Britain. I: Eradication of the disease from cattle and the role of the badger (Metes metes) as a source of Mycobacterium bovisfor cattle. Animal Regulation Studies 3, 191210.Google Scholar
Fleiss, J. L. (1973). Statistical Methods for Rates and Proportions, pp. 1517. John Wiley and Sons.Google Scholar
Gotink, W. M. & Van Ulsen, F. W. (1953). Skin lesions in cattle. Tijdschrift voor Diergeneeskunde 78, 103115.Google Scholar
Kaklson, A. G. (1962). Non-specific or cross-sensitivity reactions to tuberculin in cattle. In Advances in Veterinary Science, vol. 7 (ed. Brandley, C. A. and Jungherr, E. L.), pp. 147181. London: Academic Press.Google Scholar
Kleinhaum, D. G., Kupper, L. L. & Mouganstern, H. (1982). Epidemiologic Research. Principles and Quantitative Methods, pp. 143144. California: Lifetime Learning Publications, Belmont.Google Scholar
Little, T. W. A., Swan, C., Thompson, H. V. & Wilesmith, J. W. (1982). Bovine tuberculosis in domestic and wild mammals in an area of Dorset. TT. The badger, its ecology and tuberculosis status. Journal of Hygiene, 89, 211224.CrossRefGoogle Scholar
Macmahon, B. & Pugh, T. F. (1970). Epidemiology Principles and Methods, pp. 233234. Little, Brown and Co.Google Scholar
Muirhead, R. H., Gallagher, J. & Burn, K. J. (1974). Tuberculosis in wild badgers in Gloucestershire: epidemiology. Veterinary Record 95, 552555.CrossRefGoogle Scholar
Paterson, A. B. (1950). The incidence and causes of tuberculin reactions in non-tuberculous cattle. Advances in Tuberculosis Research 7, 101129.Google Scholar
Report (1972). Inquiry into Bovine Tuberculosis in West Cornwall. London: Ministry of Agriculture Fisheries and Food.Google Scholar
Report (1979). Bovine Tuberculosis in Badgers. London: Ministry of Agriculture, Fisheries and Food.Google Scholar
Stuart, F. A. (1984). Studies on the serological diagnosis of bovine tuberculosis. M. Sc. Dissertation. Department of Microbiology, University of Surrey.Google Scholar
Wilesmith, J. W. (1983). Epidemiological features of bovine tuberculosis in cattle herds in Great Britain. Journal of Hygiene 90, 159176.CrossRefGoogle ScholarPubMed
Worthington, R. W. (1967).Mycobacterial PPD sensitins and the non-specific reactor problem Onderstepoort Journal of Veterinary Research 34, 345–138.Google Scholar