Nighttime Applications of Two Formulations of Pyrethroids are Effective Against Diurnal Aedes albopictus

The successful control of Aedes albopictus requires a multifaceted approach using a variety of integrated pest management techniques. Because this species is diurnal, nighttime ultra-low volume adulticide applications seem likely to miss resting mosquitoes and, therefore, are often met with skepticism. The goal of this study was to compare the efficacy of nighttime applications of pyrethroids with and without prallethrin to control caged and field populations of Ae. albopictus. During August and September of 2015, 2 adulticide applications were performed, treating 4 urban sites in the city of Trenton. We compared Anvil®, which contains sumithrin and piperonyl butoxide (PBO), to Duet™, which contains sumithrin, prallethrin, and PBO. Because prallethrin excites resting mosquitoes to flight, we hypothesized that Duet would kill more mosquitoes, especially those resting in cryptic harborages. Comparing pretreatment and posttreatment adult mosquito numbers, Biogents Sentinel trap collections revealed twice as many mosquitoes were killed by Duet than by Anvil. For caged Ae. albopictus, both products performed comparably, with Duet achieving a slightly higher mortality in front yards and Anvil achieving a slightly higher mortality in backyards. It is clear that nighttime adulticide applications are effective against Ae. albopictus, and the need to continue efficacy data collection is important because adulticiding is a key component of disease control response.