Figure 6
Distribution of the regional proportion of holdings positive for VTEC O157. The proportion holdings positive for VTEC O157 the first day in each quarter of the year in each of the eight NUTS level 2 regions in Sweden. Each boxplot represents data from simulations of VTEC O157 spread in the complete Swedish cattle population during the period 2005-07-01 to 2013-12-31. The simulations are initialised both from a prevalence according to observed data [39, 40] and from a uniform initial holding prevalence of 20% and all individuals infected in the infected holdings. In each region a random set of 126 holdings were selected and the herd status determined from simulated data. A generalised additive model (GAM) was fitted and the predicted proportion holdings that were infected in each NUTS 2 region were calculated for 1000 simulated trajectories.