Figure 2

Cumulative probability distribution of pre-survey prevalence with increasing numbers of positive samples detected. Effect of increasing residual herd prevalence (HP) on the pre-survey prevalence estimates prior to the consecutive survey at a threshold HP of 0.2% (vertical black bar). Pre-survey herd prevalence was estimated using cumulative herd prevalence beta-distributions defined by a fixed sample size (N = 2400) and increasing numbers of positive samples