Appendix A. A figure showing ratio of the probability of disease occurrence in a finite population *ψ*[1-(1-*p'*)*N*] to the probability of disease occurrence in an infinite population, *ψ*.

FIG. A1. Ratio of the probability of disease occurrence in a finite population ψ[1-(1-p')N] to the probability of disease occurrence in an infinite population, ψ. The ratio approaches 1 as finite population size (N) increases and detectability (p) increases. |