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.