Repellent Research Focusing on Mosquito Blood-sucking Behavior

Effect of Silicone Oil

The results of observing the accretion behavior of mosquitoes on a surface coated with a hydrophilic/hydrophobic liquid are reported.

Observation of mosquito accretion behavior

We applied a hydrophilic and hydrophobic liquid and observed the behavior of mosquitoes accreting on the applied surface. When glycerin was applied, mosquitoes showed various behaviors, such as flying away immediately, staying for a long time, and walking around in search of a blood source. The contact time with the applied surface was widely dispersed. This was the same when it was not applied. However, when the hydrophobic liquid silicone oil or squalene was applied, the contact time was greatly shortened, and no mosquitoes continued to accrete for more than 3 s, especially with silicone oil.

Fig. 1 Chamber used to measure mosquito contact time

Diagram explaining chamber apparatus used for measuring mosquito contact time. This chamber provides host cues such as odour, heat, carbon dioxide, and visual contrast to promote mosquito landing on ground-glass substrates.

(reference: modified from Iikura et al., Sci Rep 10, 14480 [2020])

Fig. 2 Leg contact time of mosquitoes accreted on a substrate coated with various liquids

Samples with different letters (A, B) on the plot show statistically significant differences (Tukey post hoc test, p <0.001) (reference: modified from Iikura et al., Sci Rep 10, 14480 [2020])