Portal de Periódicos da CAPES

The transmission dynamics of the aetiological agent of scrapie in a sheep flock

2000; Elsevier BV; Volume: 168; Issue: 2 Linguagem: Inglês

10.1016/s0025-5564(00)00048-1

1879-3134

Thomas J. Hagenaars, Christl A. Donnelly, Neil M. Ferguson, Roy M. Anderson,

Trace Elements in Health

We formulate and investigate the properties of a model framework to mimic the transmission dynamics of the aetiological agent of scrapie in a sheep flock. We derive expressions for summary parameters that characterize transmission scenarios, notably the basic reproduction number R(0) and the mean generation time T(g). The timescale of epidemic outbreaks is expressed in terms of R(0) and cumulants of the generation time distribution. We discuss the relative contributions to the overall rate of transmission of horizontal and vertical routes during invasion and in endemicity. Simplified models are used to obtain analytical insight into the characteristics of the endemic state.