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The massive and inappropriate use of synthetic insecticides is causing significant and increasing environmental disruption. Therefore, developing effective natural mosquitocidal compounds could be an alternative tool for malarial vector control. The present study investigates the larvicidal and adulticidal effect of methanol and acetone extracts of leaves from Lippia chevalieri, Lippia multiflora, Cymbopogon schoenanthus, and Lantana camaraagainst Anopheles arabiensis, to control the most widespread vector transmitting malaria in sub-Saharan. Africa. Extracts were evaluated following WHO modified test procedure against third- to fourth-instar larvae and, non-blood-fed females from 3- to 5-day-old field populations of An. arabiensisunder laboratory conditions using WHO larval and CDC bottle bioassays, respectively. Mortality was recorded after 24-h exposure and several compounds were identified in the extracts. The methanolic and acetonic extracts of L. camarawere effective against larvae showing lethal concentrations to 50% (LC50) of the population, at 89.48 and 58.72 ppm, respectively. The acetonic extracts of C. schoenanthusand L. chevalierishowed higher toxicities LC50s of 0.16% and 0.22% against female adults, respectively. The methanolic extracts of L. multifloraand L. chevalieriLC50s were effective at 0.17% and 0.27%, respectively, against female adults. These results indicate that the plant extracts tested may represent effective means to control An. arabiensiswhen used to treat the surface of the marshes.

Resistance to pyrethroid insecticides involving kdrmutations is widespread in Aedes aegypti(L.) (Diptera: Culicidae) and potentially could impact control efforts in endemic countries. Dengue cases had been sporadic in Burkina Faso for over a decade prior to the 2016–2017 outbreak that resulted in 15,074 suspected cases and 36 deaths, mainly in Ouagadougou. These outbreaks highlighted the lack of information on numerous aspects of the biology, behaviour and insecticide status of local dengue vector populations that are fundamental to vector control. We investigated the insecticide resistance profiles and the kdrmutations involved in pyrethroid resistance of Ae. aegyptifrom Somgandé, a district of Ouagadougou. WHO bioassays revealed that the local Ae. aegyptipopulations were highly resistant to pyrethroids with mortalities of 15% for permethrin and 37% for deltamethrin. Resistance to carbamates was also detected with mortalities of 55% for propoxur and 90% for bendiocarb, but high mortalities (> 97%) to organophosphates (malathion and fenitrothion) indicated susceptibility. Allele-specific PCR and voltage-gated sodium channel gene sequencing showed a very high frequency (97%) of the F1534C kdrallele whilst the V1016I kdrmutation frequency was 46%. Association of dual-locus kdrmutations was detected for permethrin resistance. We conclude that in this locality of Burkina Faso, Ae. aegyptiis resistant to pyrethroid and carbamate insecticides but remains susceptible to organophosphates, providing useful information for possible future control.