Insecticide resistance and its molecular basis in urban insect pests

Insecticide resistance is one of the most important evolutionary phenomena for researchers. Overuse of chemicals has induced resistance in insect pests that ultimately has led to the collapse of disease control programs in many countries. The erroneous and inappropriate management of insect vectors has resulted in dissemination of many vector-borne diseases like dengue, malaria, diarrhea, leishmaniasis, and many others. In most cases, the emergence of new diseases and the revival of old ones can be related with ecological changes that have favored rapid growth of vector densities. Understanding molecular mechanisms in resistant strains can assist in the development of management programs to control the development and spread of resistant insect populations. The dominant, recessive, and co-dominant forms of genes encoding resistance can be investigated, and furthermore, resistance development can be addressed either by the release of susceptible strains or timely insecticide rotation. The present review discusses the resistance level in all important insect vectors of human diseases; the molecular basis of evolvement of resistance has also been discussed.