Repellents used against Aedes aegypti bites: synthetic and natural origin

Melissa Noguera-Gahona Cindy Peña Natalia Quñones-Sobarzo Caroline Ruth Weinstein-Oppenheimer María Elízabeth Guerra Zúñiga Ximena Collao-Ferrada ^*

• Universidad de Valparaiso, Valparaíso, Chile

Dengue fever is a disease transmitted by mosquitoes of the Aedes genus, in particular Aedes aegypti, and has emerged as a global health issue. With the expansion of the mosquito to new geographical areas, driven by factors as climate change, the need for preventive measures like the use of insect repellents has become critical. The present review explores the current state of the art on topical mosquito repellents, both synthetic and natural used globally, especially in regions where dengue is endemic. Among the synthetic repellents, DEET has been the one most widely used and is backed by investigations that have demonstrated its efficacy and safety, although there are concerns about its toxicity in exceptional cases. Other compounds like picaridin, IR3535, and PMD are also common, and offer alternatives with variable profiles of safety and efficacy. As for natural repellents, essential oils such as citronella, lemon eucalypt, and clove have proven to be effective against Aedes aegypti, although they pose challenges related to the rapid volatilization and limited duration of their protective effect. Combinations of essential oils and synthetic compounds have been proposed to improve efficacy and safety. Finally, the review highlights the complexity, and the challenges associated with the development of new repellents, including the high cost and long time needed for their commercialization, as well as the importance of continued research to improve the efficacy and safety of these products.