Deploying dengue-suppressing Wolbachia: robust models predict slow but effective spatial spread in Aedes aegypti

摘要: A novel strategy for controlling the spread of arboviral diseases such as dengue, Zika and chikungunya is to transform mosquito populations with virus-suppressing Wolbachia. In general, Wolbachia transinfected into mosquitoes induce fitness costs through lower viability or fecundity. These maternally inherited bacteria also produce a frequency-dependent advantage infected females by inducing cytoplasmic incompatibility (CI), which kills embryos produced uninfected mated males. competing effects, frequency-independent costs, bistable frequency dynamics. Above threshold frequency, denoted p, CI drives fitness-decreasing transinfections local populations; but below infection frequencies tend decline zero. If p not too high, spatial once infections become established over sufficiently large areas. We illustrate how simple models provide testable predictions concerning temporal dynamics introductions, focusing on rate spread, shape spreading waves, conditions initiating from introductions. First, we consider robustness diffusion-based incorporating two important features wMel-Aedes aegypti biology that may be inconsistent diffusion approximations, namely fast induced complete (i.e., all incompatible crosses die) long-tailed, non-Gaussian dispersal. With CI, our numerical analyses show long-tailed dispersal changes wave-width only slightly; it can significantly reduce wave speed relative prediction; allows smaller introductions initiate spread. Second, use approximations distances predict outcome 2013 releases wMel-infected Aedes in Cairns, Australia, Third, describe new data near Australia demonstrate long-distance an approximate bound wMel northeastern Australia. Finally, apply operational guidelines efficient transformation vector even very slow order 10-20 m/month (as predicted), area-wide population within few years following initial covering about 20-30% target area.