Insecticidal activity of essential oils from six aromatic plants against Aedes aegypti, dengue vector from two localities of Ouagadougou, Burkina Faso

Dengue is an important vector-borne infectious disease transmitted by Aedes aegypti in the tropics and subtropics. While synthetic chemicals have been used to control mosquitoes, an increase in their use in agricultural and public health domains has led to the development of insecticide resistance in mosquito populations. Hence, there is an increasing interest in biological insecticides as alternatives to synthetic insecticides, as part of insecticide resistance management strategies. The aim of the current study was to assess the bioactivity of essential oils from six (06) aromatic plants Cymbopogon giganteus, Cymbopogon nardus, Cymbopogon schoenanthus, Eucalyptus camaldulensis, Lippia multiflora, and Ocimum americanum against Ae. aegypti larvae and adults. Larvicidal and adulticidal bioassays were performed according to the World Health Organization (WHO) standard methods using field-collected Ae. aegypti from 1200 Logements and Tabtenga, two localities of Ouagadougou. The Rockefeller-susceptible strain was used as control. The essential oil of Lippia multiflora was the most toxic against Ae. aegypti larvae with 50% lethal concentration (LC50) of 73.51 and 79.18 ppm for 1200 Logements and Tabtenga populations, respectively. This essential oil also had the most effective adulticidal activity against Ae. aegypti from both 1200 Logements (LC50 = 0.47%) and Tabtenga (LC50 = 0.51%). The essential oil of O. canum was less toxic against the larvae and adults of Ae. aegypti, whereas the essential oils of other plants tested had intermediate activity against either the larvae or adults. No significant difference in susceptibility was observed between field mosquitoes and the Rockefeller-susceptible strain based on insecticide resistance ratios. The results suggest that all the tested essential oils exhibited toxicity against larvae and adults of Ae. aegypti and can therefore be used as biological and ecofriendly insecticides for dengue vector control. However, field evaluations of formulations and further research on the essential oils for potential toxicology toward non-target organisms are necessary.