This will not completely eliminate all mosquitoes. Killing adult mosquitoes (adulticiding) – or spraying – helps to control the size of mosquito populations and prevent the spread of disease. Mosquito populations are constantly dying off and regenerating, and adulticiding will not eliminate all of the adult mosquitoes in the community. Adulticiding is needed because source reduction (reducing unnecessary standing water), surveillance and larviciding (killing the mosquito population at the larval stage) alone are not enough to control mosquito populations.

Duet is effective in controlling disease-spreading mosquitoes. A specific area is identified and treated, but the spraying in this targeted area is not reaching an entire habitat of mosquitoes. Sometimes mosquitoes move into the spray zone from outside of it after it is treated, which is called “reinfestation” (i.e., they drift in on wind currents from areas that have not been treated). When mosquito reinfestation occurs, additional sprayings may need to be considered to control the spread of mosquitoes that transmit disease. Effectively controlling an adult mosquito population through spraying also depends on a number of external factors, including timing, the level of reinfestation, methodology used during the application and weather conditions.