NR AEZX
AU Hagenaars,T.J.; Ferguson,N.M.; Donnelly,C.A.; Anderson,R.M.
TI Persistence patterns of scrapie in a sheep flock
QU Epidemiology and Infection 2001 Aug; 127(1): 157-67
PT journal article
AB The epidemiology and transmission dynamics of sheep scrapie is as yet poorly understood. Here we present a theoretical analysis of the transmission dynamics within a sheep flock, concentrating on how persistence properties depend on transmission scenario and flock size. Patterns of disease persistence and extinction are studied analytically using branching-process approximations and numerically using stochastic model simulations. For a given basic reproduction number, disease extinction is most likely when late-stage infected animals are responsible for most of the transmission. This effect can be understood in terms of aggregation in the distribution of the number of secondary infections arising from a single primary infection. The presence of an environmental reservoir reduces the probability of extinction.
MH Animal; Disease Outbreaks/*veterinary; *Models, Theoretical; Scrapie/epidemiology/*transmission; Sheep; Support, Non-U.S. Gov't; Time Factors
AD Wellcome Trust Centre for the Epidemiology of Infectious Disease, Department of Zoology, University of Oxford, United Kingdom.
SP englisch
PO England
OR Prion-Krankheiten H