Exploring and Mitigating Insecticide Resistance in Urban Pests with New Synergists and Insecticides

This review summarizes the impact of insecticide resistance in urban pests and its implications for 'One Health' systems. Mosquitoes are the major vector of human disease via blood feeding, followed by houseflies and cockroaches via physical contact, and finally bed bugs, ants, and termites, which are not typically disease vectors. Besides overt disease, other impacts in the context of One Health include nuisance biting and resultant infections, as well as allergic reactions. Control of urban pests is still primarily achieved with insecticides, which have continually improved over time. However, their use has selected for the evolution of resistance to several compound classes across broad geographical areas and multiple species. Resistance results from several types of mechanisms: altered inherited behavioral repertoires that reduce chemical exposure, modified target sites, increased metabolism, and reduced penetration, which have recently been shown to have several specific underlying causes. Overall, the literature portrays a complex resistance landscape that highlights the importance of comprehensive, multifaceted approaches to maintain effective control. New technologies and approaches for resistance management are also discussed, with emphasis on improved chemical control measures via novel synergists and insecticides from both natural and synthetic sources.