We model the epidemic as a space-time survival process [18] . The total observation time T is the 240 days between 7 th February and 5 th October 2001. Each farm i at the location (x i , y i ) is associated with an infection time t i (if infected), a removal time r i (if slaughtered) and two integers n c i and n s i representing, respectively, the number of cattle and sheep on the farm. S c and S s represent per-capita cattle and sheep susceptibility, respectively, while I c and I s represent per capita cattle and sheep infectivity. The susceptibility is a relative measure of animal sensitivity to the disease whereas infectivity represents the infectious risk posed by an animal to others. We use a continuous kernel to describe how the probability of contact between farms scaled with distance. Transmission is naturally assumed to decrease with the distance between farms according to the power law