Mosquito release and recapture
Batches of 200 uninfected and unfed female mosquitoes aged 3-5 days from the resistant or susceptible colonies were gently mouth-aspirated into a clean paper cup. The mosquitoes were sugar starved for 6 hours before releases and color-marked with green (for the susceptible colony) and pink (for resistant colony) fluorescent powder to distinguish them after simultaneous release in the semi-field environment. Mosquito releases were done outside the hut and at the same time of day (1840hrs) to avoid circadian cycle effects. The volunteer entered the bed net 30 mins after the release of the mosquitoes. Fifteen (15) tests were conducted with each net (treated or untreated net). The release was done every 3 days to allow for the wash-out period. Windows of huts were fitted with exit traps to catch exiting mosquitoes (Fig. 1E). The floor of the hut was covered by white sheets to ease the collection of knocked-down mosquitoes. Host seeking mosquitoes trapped in the bed net trap were collected and recorded (Fig. 1D). Validation of these behaviors was done using the F1 progeny obtained from An. gambiae s.s caught from the field.