4. WHO insecticide susceptibility tests
The resistance profile to public health insecticides was determined using the WHO susceptibility bioassays protocol (WHO, 2016). About 100 female mosquitoes aged 2-5 days old were exposed to the insecticide(s) for either 30 minutes or 1 hour, then transferred to holding tubes and provided with 10% sucrose solution. Fifty mosquitoes exposed to non-impregnated papers were used as a control group. The initial knockdown effect was scored immediately after exposure time, while the mortality rates were scored 24 hours post-exposure. These bioassays were conducted at 26 ± 2°C and 80 ± 10% relative humidity.