WHO cone bio-assay to determine bed-net efficacy
The treated net insecticidal efficacy was confirmed by exposing
mosquitoes for 3 mins according to the standard WHO cone bioassay
procedure. This was done with 4–5day old, non-blood fed, An.
gambiae s.s . The bioassays included 5 replicates from both the
resistant and susceptible colony with an average of five mosquitoes per
tube. The cone bioassays were conducted using DawaPlus 2.0 long-lasting
insecticidal net treated with deltamethrin. The F1 progeny of
wild-caught mosquitoes were also used for this experiment for
validation. After exposure, the groups of mosquitoes were placed in a
single 1 L paper cup and provided with cotton wool soaked with 10%
sugar solution for 24 hrs. Their knock-down status was measured 60 min
post-exposure and mortality were recorded after 24 h. An untreated net
was used as a negative control for the assay.