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Arthropod-borne viral diseases are important public health threats in tropical countries. In the Americas, diseases such as Dengue, Zika, Chikungunya, Mayaro, and Yellow fever, which are mainly transmitted by Aedes aegypti L. are responsible for high rates of morbidity and mortality in the populations. The incidence of those viruses has increased in the last few years, due to the decrease of vector control programs, as well as, the resistance of this vector in front of many products that have been used in this proposal. Plant-based products such as essential oils are a promising alternative for Ae. aegypti control. In this context, the present work aims to investigate the seasonality effect on the larvicidal potential and safety of essential oils from 4 endemic plants of the Brazilian Amazon, as well as to verify their larvicidal activity and safety. The species were collected in the rainy and dry periods (Eugenia uniflora L., Lantana camara L., Ocimum basilicum L., Plectranthus neochilus Schlrt.). The essential oils were extracted by hydrodistillation and chemical composition was determined by gas chromatography coupled to mass spectrometry. The larvicidal activity was performed according to the methodology recommended by the World Health Organization. The safety of the oil use was evaluated against two non-target organisms: Artemia salina Leach and Danio rerio Hamilton Buchanan. Essential oils of E. uniflora, L. camara, O. basilicum, P. neochilus, presented as major compounds, in both collection periods, the substances Curzerene, Germacrene D, Methyl chavicol and, Caryophyllene, respectively. However, showed a qualitative and quantitative variation of this composition. All oils showed promising results against Ae. aegypti larvae with LC 50 between 41.7 and 275.8 μg/mL. They were efficient against Ae. aegypti but showed high toxicity to non-target organisms, requiring additional safety studies. Despite these results showing that those essential oils are not ideal larvicides because they presented toxicity to non-target organisms, bioprospection is a promising tool to help reduce the dissemination of arboviruses, and they can use in artificial breeders of Ae. aegypti larvae, where water will not be reused for human consumption or have other cohabiting organisms., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Inc. All rights reserved.)

This review focused on the toxicity of essential oils and their constituents against Aedes aegypti L. (Diptera, Culicidae) larvae, a key vector of important arboviral diseases, such as dengue, chikungunya, zika, and yellow fever. This review is based on original articles obtained by searching major databases in the last six years. Our literature review shows that 337 essential oils from 225 plant species have been tested for larvicidal bioactivity. More than 60% of these essential oils were considered active (LC 50 <100 µg/mL). Most species belong to the families Lamiaceae (19.3%), Lauraceae (9.9%), and Myrtaceae (9.4%). The plants studied for their larvicidal activity against A. aegypti were mainly collected in India and Brazil (30 and 20%, respectively) and the parts of the plants most used were the leaves. Less than 10% of essential oils were evaluated for toxicity against non-target organisms and with the aim to demonstrate safe use. The most used plant parts are leaves and the main compounds of essential oils were described. The most active essential oils are rich in sesquiterpene hydrocarbons, oxygenated sesquiterpenes, and monoterpene hydrocarbons. Here, factors affecting bioactivity (chemical composition, plant parts, and harvesting site) of essential oils and their constituents, as well as safety to non-target organisms are discussed. Essential oils have considerable potential against A. aegypti. This review shows that essential oils might be used to control arboviruses, and further studies on safety and formulations for application in the field should be performed., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This review aims to describe essential oils and their constituent compounds that exhibit bioactivity against Aedes aegypti L. (Diptera: Culicidae) larvae, the immature stage of the primary vector of dengue. This review is based on original articles obtained by searching on major databases. Our literature review revealed that 361 essential oils from 269 plant species have been tested for their larvicidal activity. More than 60 % of these essential oils were considered active (LC50<100 mg/L), and the majority of these active oils were derived from species belonging to Myrtaceae, Lamiaceae, and Rutaceae. The most active essential oils exhibited effective concentrations comparable with the dosage recommended for the use of temephos in container breeding. Approximately 27 % of the plants studied for their larvicidal activity against A. aegypti were collected in Brazil. Essential oils rich in phenylpropanoids, oxygenated sesquiterpenes, and monoterpene hydrocarbons were found to be the most active. When the isolates were tested, phenylpropanoids and monoterpene hydrocarbons were the most active compound classes. We describe the plant parts used and the major constituents of the essential oils. In addition, we discuss factors affecting the activity (such as plant parts, age of the plant, chemotypes, larval source, and methods used), structure-activity relationships, and mechanisms of action of the essential oils and their compounds. Essential oils have been widely investigated and show high larvicidal activity against A. aegypti. This review reveals that the essential oils are effective alternatives for the production of larvicides, which can be used in vector-borne disease control programmes.