228 - Evaluating the Efficacy of Outdoor Residual Spraying (ORS) for Aedes aegypti Control in Ponce, Puerto Rico

Abstract: The control of Aedes aegypti, the primary vector of dengue, chikungunya, and Zika, is a public health priority in Puerto Rico, but it is only one of 40 mosquito species on the island. Like many areas in the continental US, there are pest control companies in Puerto Rico that offer general mosquito control using Outdoor Residual Spraying (ORS) delivered as a barrier or perimeter application. While there is clear evidence that these treatments reduce mosquito populations, the data do not distinguish the level of control by species. This study was conducted to specifically determine the level of Ae. aegypti control obtained through this technique.

In collaboration with Rentokil Terminix, the Puerto Rico Vector Control Unit (PRVCU) conducted a field evaluation of ORS using Suspend Polyzone™ in the municipality of Ponce, Puerto Rico. The study targeted the backyards of homes with monthly applications initiated on September 17, 2024.

To monitor mosquito populations at each home, Autocidal Gravid Ovitraps (AGO) were installed in treated areas and additional AGO traps were installed around untreated control homes. All ORS applications were applied by professional applicators from Rentokil Terminix using their standard field service protocol for mosquito control. PRVCU technicians monitored and serviced the AGO traps. All data analysis was performed by PRVCU’s in-house data analysis group.

Results were not available at the time of this abstract’s preparation but will be reported in the presentation.