Pyrethroid-resistance-associated L1014F kdr-type mutation in the voltage gated sodium channel gene was detected in 30/53 flies. Ten to 34.5% of flies were heterozygous for acetylcholinesterases target-site insensitivity, associated with organophosphate and carbamate resistance. Elevated activity levels of glutathione S-transferase (3%, 7%, 12.5% and 14%) and esterase (2%, 5%, 5.5% and 6.5%) were detected in flies that originated from Mirigama, Pannala, Thalawa and Mamadala respectively, while monooxygenase quantities remained below the cut-off level. The percentage of knocked-down sand flies was < 75% at any tested concentration, including those, which exhibited 100% mortality after 24 h.
The lowest susceptibility levels (except for deltamethrin) were detected in the Mamadala population, whereas the highest levels were detected in the Mirigama population. Insecticide -susceptibility levels were higher than the discriminating dosages established for Aedes mosquitoes, except for malathion. Extracted fly DNA samples were tested for the presence of knockdown-resistance ( kdr) type mutations. Metabolic enzyme activity and the sensitivity of the acetylcholinesterase target-site were determined by biochemical assays using wild-caught flies. Post-1-h knockdown and post-24-h mortality were recorded and analyzed. argentipes were exposed to different concentrations of DDT, malathion, deltamethrin and propoxur using WHO susceptibility bioassay kits. MethodsĪdult sand flies were collected using standard cattle baited net traps and CDC light traps from selected sites in four districts. argentipes were investigated with exploration of probable underlying resistance mechanisms. Here, insecticide susceptibility patterns of P. Limited knowledge on biological and behavioral characteristics of probable vector Phlebotomus argentipes hinders disease control. Leishmania donovani-induced and sand fly-transmitted leishmaniasis is a growing health problem in Sri Lanka.
0 kommentar(er)
