Assessing the potential of nano-formulated chlorfenapyr and clothianidin insecticides-treated sugar baits against Anopheles funestus, Anopeles coluzzii and Culex quinquefasciatus mosquitoes.

ABSTRACT

Mosquitoes serve as vectors for various diseases like malaria, dengue fever, yellow fever, and lymphatic filarial diseases causing significant global health problems, highlighting the importance of vector control. The study was conducted to assess the effectiveness of nanoformulated clothianidin and chlorfenapyr insecticides treated with ATSB in controlling three mosquito strains. The development of a natural thiolated polymer-coated ATSB nano formulation involved incorporating nano-carriers to deliver insecticides. Field- collected mosquito strains were subjected to laboratory-based bioassays using 1 % and 1.5 % concentrations of each conventionally used and nanoformulated insecticide with ATSB solution. Adult mosquitoes were left overnight to contact with N-ATSB and efficacy was recorded after 36 and 72 h. The results showed that nanoformulated chlorfenapyr was significantly more effective as compared to clothianidin against An. funestus and Cx. quinquefasciatus but the results were not significantly different against An. coluzzii (100 %). An. coluzzii was found to be the most susceptible strain followed by An. funestus and showed 100 % and ∼ 98 % mortality against nanoformulated chlorfenapyr (1.5 %). Nanoformulated clothianidin induced more than 92 % and ∼ 100 % mortality against An. funestus and An. coluzzii respectively. However, Cx. quinquefasciatus significantly showed less mortality against nanoformulated clothianidin (88 %) and chlorfenapyr (>95 %) as compared to Anopheline strains. Furthermore, results indicate that nanoformulated insecticides significantly caused greater and prolonged fatality as compared to conventional form, suggesting effective and suitable strategies for vector management.