Figure 3
From: Target product profiles for protecting against outdoor malaria transmission
Progressive impact upon a completely outdoor transmission system (π i = 0) of products with increasing efficacy of personal protection (ρ o ) achieved by either repelling (θ Δ,o ) or killing (θ μ,pre,o ) attacking mosquitoes before they feed upon human users. The grey arrows represent interpolation of the efficacy thresholds at which the toxic mode of action achieves equivalent transmission control to the theoretical limit at complete protective efficacy (θΔ,o = 1·0 so ρo = 1·0) for spatial repellents at high coverage (Ch = 0·8). Impact is expressed in terms of the mean relative risk of exposure experienced by the average community member (ψh,Ω). Further details of the model and symbol definitions are available online (See Additional file 4)