Figure 13

A schematic representation of how various alternative strategies for targeting vector mosquitoes when they utilize specific resources can suppress (Green) or redistribute, stabilize and even increase (Red) malaria transmission, depending on values for measurable behavioural parameters of the mosquito population and its interaction with interventions [8, 10, 11, 13–15, 80]. Red and green ovals indicate effects upon malaria transmission, with the magnitude of their impact indicated by their size. The relative magnitude of persisting transmission after intervention (ψ) is expressed as a function of: (1) the utilization rate (α) or probability (Q) of targetable subsets (x) of a defined resource (R, which may be specified as blood (v), resting sites (r), sugar (s) or aquatic larval habitat (a)); (2) the coverage of that resource subset (R _x ) achieved$\left(C_{R_x}\right)$; (3) the mortality probability (μ) of mosquitoes utilizing covered forms of that resource subset; where human blood is the targeted resource, (4) the personal protection (ρ) afforded as a result of repellence, irritance or physical deterrence (Δ) combined with fast-acting toxicity that occurs before the mosquito can feed (μ _pre ); and (5) the proportion of exposure that would otherwise occur when that intervention is used$\left({\pi }_{R_{x,y}}\right)$. For all parameters described, values approaching or exceeding one are considered high and values approaching zero are considered low. The subscripts h, l and i refer to the subsets human, livestock and indoors.