Fig. 4.

Relatedness of parasite haplotypes within asymptomatic infections. Panel A shows the observed frequency distribution of pairwise allele-sharing (ps) between parasite haplotypes recovered from the same or different infections. Grey bars denote comparisons between infections while black bars show within-infection comparisons. Panel B shows simulated allele-sharing (ps) distributions expected of parasites in the different classes of relatedness. We simulated ps expected of haploid parasites derived from the same inbred oocyst (100% identity-by-descent; IBD), from the same outcrossed oocysts (50% IBD), from two related oocysts (25% IBD) and from two unrelated oocysts (0% IBD). Upper and lower confidence limits for these ps distributions are shown in Table 1 and define thresholds for categorizing parasite haplotypes into different classes of relatedness.