The enormous burden placed on populations worldwide by mosquito-borne diseases, most notablymalaria and dengue, is currently being tackled by the use of insecticides sprayed in residences orapplied to bednets, and in the case of dengue vectors through reduction of larval breeding sites orlarviciding with insecticides thereof. However, these methods are under threat from, amongst otherissues, the development of insecticide resistance and the practical difficulty of maintaining long-term