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Modelling bovine spongiform encephalopathy

Published online by Cambridge University Press:  14 January 2008

J. H. M. THORNLEY  and
J. FRANCE
J. H. M. THORNLEY*
Affiliation:
Centre for Nutrition Modelling, Department of Animal & Poultry Science, University of Guelph, Guelph, ON, N1G 2W1, Canada
J. FRANCE
Affiliation:
Centre for Nutrition Modelling, Department of Animal & Poultry Science, University of Guelph, Guelph, ON, N1G 2W1, Canada
*
*To whom all correspondence should be addressed.
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Summary

A deterministic model for the spread of an important animal disease, bovine spongiform encephalopathy (BSE), is described. It is a sparse three-pool model, the pools corresponding to susceptible, infected and sick animals. Simulations illustrate the biological meaning of the parameters, and pinpoint how parameters affect epidemic characteristics: infectivity impacts on the leading edge of the epidemic and its intensity. The times when infection is introduced and when control is exercised determine the length and possibly the intensity of the epidemic. Finally, the (single) incubation rate influences the trailing edge of the epidemic. It is applied to data describing the recent UK BSE outbreak, with reasonable success. Apart from a scaling factor, only these four quantities were adjusted to achieve this. The contributions from greater modelling complexity are discussed. It is concluded that the simple model is well suited for grasping the essentials, whereas further detail is needed for a more mechanistic representation, in particular concerning incubation delays in developing infectiousness and clinical sickness.

Type
Modelling Animal Systems Paper
Information
The Journal of Agricultural Science , Volume 146 , Issue 2: Modelling Animal Systems , April 2008 , pp. 183 - 194
Copyright
Copyright © Cambridge University Press 2008

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