Increasing insecticide resistance reduces the effectiveness of vector control. Monitoring vector resistance is essential to understand its evolution and design effective responses. In this study, we monitored patterns of insecticide resistance, vector population biology, and genetic variation associated with resistance in Uganda over a three-year period from 2021 to 2023. In Mayuga, Anopheles funestus ss was the dominant species, but there was evidence of hybridization with other An. funestus species. Sporozoite infestation was relatively high, peaking at 20.41% in March 2022. Strong resistance was observed to pyrethroids at 10 times the diagnostic concentration, but susceptibility was partially recovered in the PBO synergy test.
Map of mosquito collection sites in Mayuge District. Mayuge District is shown in brown. Villages where collections were made are marked with blue stars. This map was created using the free and open source software QGIS version 3.38.
All mosquitoes were maintained under standard mosquito culture conditions: 24–28 °C, 65–85% relative humidity, and a natural 12:12 daylight period. Mosquito larvae were reared in larval trays and fed tetramine ad libitum. Larval water was changed every three days until pupation. Emerged adults were maintained in Bugdom cages and fed a 10% sugar solution for 3–5 days prior to bioassay.
Mortality in the pyrethroid bioassay at the F1 stage. Spot mortality of Anopheles mosquitoes exposed to pyrethroids alone and to pyrethroids in combination with synergists. Error bars in the bar and column charts represent confidence intervals based on the standard error of the mean (SEM), and NA indicates that the test was not performed. The red dotted horizontal line represents the 90% mortality level below which resistance is confirmed.
All datasets generated or analyzed during this study are included in the published article and its Supplementary Information files.
The original online version of this article has been modified: The original version of this article was mistakenly published under a CC BY-NC-ND license. The license has been corrected to CC BY.
Post time: Jul-21-2025