Monoterpenes: Promising natural products for public health insect control- A review

Insects of medical importance are the most harmful pests impacting the human health as they are vectors to many human diseases. The fight against these insects is mainly based on the use of synthetic insecticides. However, an inappropriate use of these chemicals, can cause harmful impact on the environment and human health, and/or the development of resistance in insects. Therefore, natural products, including botanicals can be effective alternatives to synthetic insecticides for the control of these vectors. Among the plant products, monoterpenes have been widely studied for their insecticidal activity against insects of public health importance. In this regard, monoterpenes are known to show toxic (fumigant and contact toxicity), repellent, antifeedant, ovicidal and sterilizing effects against mosquitoes, flies, lice, fleas, bed bugs and cockroaches. In this review, we focus on studies describing the bioactivities of monoterpenes against these public health insects. The chemistry, mode of action and structure–activity relationship of monoterpenes are also discussed.