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Abstract Background The interest in larvicides of plant origin is generally renewed in vector control because of their safety compared to synthetic larvicides. However, there are concerns about the relative safety dose of these phytochemicals on non-target organisms which led to the development of plant derived nanoparticles. In this study, we examined the bioefficacy of low doses of two green synthesized nanoparticles on immature stages of Anopheles mosquitoes in Nigeria. Aqueous plants (Moringa oleifera and Ficus exasperata) extracts were used in the biosynthesis. The prepared Ag-NPs were characterizations using Fourier-transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy, and scanning electron microscopy (SEM). Third and early fourth instars of known susceptible laboratory strains of Anopheles gambiae s.s. (KISUMU strains) and pyrethroid resistant field strain of An. gambiae were exposed to serial dilutions of 0.25, 0.5, 0.75, 1.0 and 2.5 ppm of each phyto nanoparticles. Moribund and dead larvae were observed after 24 and 48 h post exposure, and the results were analysed with descriptive statistics. Results With the laboratory mosquitoes, Moringa oleifera AgNP effected high mortalities of 88–100% (LC50 = 0.39 ppm; LC95 = 0.62 ppm) at 24 h post exposure except at the lowest concentration, while Ficus exasperate AgNP induced a 32–100% mortality (LC50 = 0.51 ppm; LC95 = 1.15 ppm) except at the lowest concentration. In the field populations, mortality in Moringa oleifera and Ficus exasperata was 23–93% (LC50 = 0.65 ppm; LC95 = 2.28 ppm) and 37–50% (LC50 = 1.51 ppm; LC95 = 391.64 ppm) respectively. There was no significant difference in mortality values between the laboratory and field strains (P

Abstract Background Aedes aegypti transmits several arboviral diseases of global public health threat such as dengue, zika, and yellow fever. Recently, a series of yellow fever outbreaks have been reported in different parts of the country. Globally, the control of mosquito-borne diseases has relied heavily on insecticides based vector control efforts. Therefore, we assessed the susceptibility status to three different classes of WHO approved insecticides and evaluated the importance of detoxifying enzymes on insecticides resistance in Aedes aegypti collected from Lagos State, Nigeria. Aedes aegypti immature stages were collected from suitable habitats in peri-domestic areas of Alimosho, Kosofe, Badagry, and Ibeju-Lekki Local Government Areas (LGAs) of Lagos State, 2–5 days old glucose-fed adult female mosquitoes were exposed to discriminating doses of DDT, permethrin, bendiocarb, and PBO synergist using WHO standard procedure and kits. Identification was through morphological means only. Results Resistance to DDT and permethrin was recorded in all the LGAs, suspected resistance to bendiocarb was recorded in Aedes aegypti from Alimosho while full susceptibility was recorded in other LGAs. PBO synergist significantly increases the 24 h mortality of DDT and permethrin-resistant Aedes aegypti in all the LGAs. The activities of both GSTs and cytochrome P450s increase with decreasing mortality for Aedes aegypti, regression value (R 2) ranges from 0.8889 to 0.6224 for GSTs and 0.4379 to 0.616 for cytochrome P450s. Conclusions Aedes aegypti population from Lagos State, Nigeria, have developed resistance to DDT and permethrin, the activities of P450s and GST were implicated in DDT and permethrin resistance in this study. Therefore, a need for regular insecticides monitoring and PBO should be incorporated into Aedes aegypti insecticides control strategies to forestall development of resistance to DDT and pyrethriods.