Insecticide resistance in disease vectors: challenges and opportunities for effective and sustainable vector management strategies.

Achieving global health security is challenged by arthropod vectors, which transmit a wide range of vector-borne human and animal diseases. Although the safe, selective, and responsible use of insecticides continues to play a crucial role in vector management, their long-term effectiveness is increasingly threatened by the widespread emergence of insecticide resistance. Resistance evolves through natural selection acting on pre-existing genetic heritable variation in vector populations under insecticide selective pressure. In addition, exposure to insecticides induces genetic/metabolic changes, reducing insecticides' effectiveness. This review discusses the various mechanisms of insecticide resistance, how climate change affects resistance, how to manage insecticide resistance, and its implications on health security. We argue that chemical-based arthropod vector control tools should diversify molecular target sites, mode of action, improve insecticide selectivity, and integrate complementary vector control tool kits. Such an integrated approach will improve the sustainability of vector control, preserve insecticide efficacy, and reduce disease transmission.