| dc.description.abstract | Despite the global decline in malaria cases, the malaria incident rate remains high in
sub-Saharan Africa. The major remedy to deal with malaria has been the control of
malaria vectors through use of insecticides treated nets (ITNs) and indoor residue
sprays. However, this remedy is being counteracted by the threatening emergency of
insecticide resistance to different classes of insecticides among mosquito populations.
Moreover, in Uganda, in most of the parts of the country there is a near fixation of the
genes known to confirm resistance to pyrethroids (commonly used insecticide in Long-
Lasting Insecticidal Nets [LLINs]) in most mosquito vectors. To end this, there have
been a suggestion as well as implemented changes from the use of pyrethroids to
carbamates. Unfortunately, resistance to carbamates has also been observed and fully
confirmed elsewhere in Africa. Resolutely, before full implementation of the use of
carbamates there is need to understand mosquito susceptibility patterns to this class of
insecticide and the allele frequency of G119S mutation in the ace-1 (gene that confers
mosquito resistance to carbamates) in our population. This study aimed at determining
susceptibility patterns and the allele frequency of the G119S mutation in the ace-1 gene.
Anopheles gambiae (s.l.) collected from four different districts of Adjumani, Koboko,
Moyo, and Mubende found Uganda were exposed to the diagnostic concentration of
bendiocarb using WHO mosquito insecticide bioassays. The mortality rate was
calculated using Abbott’s formula. Genomic DNA from mosquito abdomen was then
extracted and rhAmp SNP genotyping was performed to detect the G119S 1 mutation
in the ace-1 gene. The allele frequency was then calculated among the mosquito
population. Mosquitoes from all study sites were resistant to the diagnostic
concentration of bendiocarb with overall mortality of 81.21% (Adjumani,78.48%;
Koboko,79.05%; Moyo, 84.03%; and Mubende, 82.41%). The overall allele frequency
of G119S mutation (ace-1
R
) was found to be 2.84% (Adjumani,4.55%; Koboko,0.00%;
Moyo, 2.44%; and Mubende, 2.84%). This study suggests that rigorous further studies
should be done to fully characterize the distribution of this resistance among different
species of Anopheles gambiae (s.l.) complex as well as other malaria mosquito vectors.
Policy makers should consider implementing enhanced insecticide resistance
surveillance in these studied areas before, during and after implementation of IRS with
bendiocarb (carbamates). | en_US |
