Fig. 1: Dose–response curves and associated distributions inferred under different pre-processing of data.

Dose–response curves for Wolbachia-free (Wolb⁻, in blue) and Wolbachia-carrier (Wolb⁺, in green) populations given data (dots) from Rio de Janeiro, Brazil¹. The original procedures (King et al.³, “Methods”) are replicated in a and c, showing the bold curves of the maximum a posteriori (MAP) estimate (King et al.³, a, c) and 50 random Monte Carlo Markov Chain estimates, almost all of which have the shape parameter (α) smaller than one, giving high densities close to zero susceptibility and a long tail towards larger values (θ is the scale parameter). Applying an alternative threshold for false positives based on the mean cycle threshold (Ct) value of five quantifiable negative controls in the original data (b, d) results in less mosquitoes being classified as infected (noticeable in b), and leads to higher estimated mean susceptibility (μ) for the Wolbachia group and less variance (σ²). As in King et al.³, these analyses exclude the first time point (3 days post infection) as it may represent transient, dose-independent presence of virus rather systemic infection.