The ability of and to penetrate LLINs and its effect on their mortality.

Variation in mosquito body size and the ability to penetrate long-lasting insecticide-treated nets (LLINs) remains unknown. This study evaluated the ability of  and to penetrate commercially available treated and untreated bednets and how this behaviour affects mosquito mortality. Three types of LLINs; DawaPlus 2.0, PermaNet 2.0, Olyset 2.0, and untreated (Safi Net) were tested inside a semi-field system. One hundred 3-5-day-old and non-starved female and were released in a chamber with a sleeping adult volunteer under a treated or untreated bednet. Mosquitoes that penetrated inside the nets were collected every two hours using a mouth aspirator. Live mosquitoes were put in paper cups, fed on glucose and their mortality rate was monitored for 48 h. The ability of to penetrate treated and untreated bednets was significantly higher than for for all three LLIN net types ( <0.001). For both species the penetration rate was higher for untreated bednets than treated ones except for the Olyset net. Regardless of the assessed mosquito species, all the mosquitoes that penetrated the net, successfully blood-fed on the sleeping volunteer. Compared to , significant mortality was recorded for that were caught inside Olyset nets within 48 hrs of monitoring ( <0.001). Conclusions: These findings demonstrate the ability of and mosquitoes to penetrate the human-occupied treated and untreated bednets. Despite this ability, mosquitoes that penetrated the bednet succumbed to death within two days.