Laboratory evaluation of drugs/systemic insecticides as endectocides through membrane feeding method: a unique...

Insecticide resistance, changing vector feeding behavior, and zoonotic transmission are key challenges for current vector control strategies. Use of endectocide drugs/systemic insecticides is a novel vector control strategy by the World Health Organization (WHO). We evaluated the efficacy of different concentrations of endectocide drugs/systemic insecticides against Anopheles stephensi and Culex quinquefasciatus by membrane blood feeding method. Experiment was conducted using 5-7 days old female mosquito in a VCRC-ANM feeder. Mortality, survival duration, and fecundity of tested mosquitoes post blood feeding was listed up to 7 days. Kaplan-Meier curves were plotted to visually analyze mosquito survival duration.

A significant difference was observed in the mortality, survival duration, fecundity, and hatchability of the mosquito (P < 0.05) between different concentrations and control. Day 3 LC₅₀ values of different drugs against Cx. quinquefasciatus and An. stephensi ranged 0.012 (Fipronil) - 12.386 μg/mL (Milbemycin oxime) and 0.007 (Ivermectin) - 1.516 μg/mL (Moxidectin), respectively. Median survival duration of Cx. quinquefasciatus after blood feeding was 1 day for Fluralaner, Sarolaner, Moxidectin, Ivermectin, Nitenpyram, and Milbemycin oxime at 0.03, 0.05, 3, 0.4, 0.15, and 30 μg/mL, respectively, and 2 days for Doramectin, Afoxolaner, Spinosad, and Fipronil at 0.7, 0.2, 1.2, and 0.015 μg/mL, respectively. For An. stephensi it was found 1 day for Fluralaner, Sarolaner, Doramectin, and Ivermectin at 0.03, 0.05, 0.65, and 0.02 μg/mL, respectively, and 2 days at 3 μg/mL Moxidectin.

Application of these drugs in livestock could provide an added advantage, as an attract-feed-kill method, to existing vector control tools. © 2025 Society of Chemical Industry.