Identifying environmental drivers of Aedes aegypti and Aedes albopictus abundance in the Dallas-Fort Worth metroplex using Random Forest modeling.

Aedes aegypti and Aedes albopictus are 2 medically important vectors that have established populations globally. In the United States, Ae. aegypti populations declined post-Ae. albopictus introduction, though both species now can be readily found throughout the Southern US. Despite overlapping distributions, there are few studies that investigate and compare the drivers of abundance at spatial scales relevant to mosquito control and surveillance districts. To address this limitation, we analyzed longitudinal mosquito surveillance data from the Dallas-Fort Worth metroplex, Texas. Dallas-Fort Worth metroplex is an area of interest due to its rapid population growth, diverse environmental conditions, and prior history with epidemic West Nile virus transmission. We trained a Random Forest model on a subset of Ae. aegypti and Ae. albopictus data and meteorological and sociodemographic variables from Tarrant and Dallas counties to predict the abundance of both species within the Dallas-Fort Worth metroplex. Additionally, we interpolated predictions to map mosquito abundance at unsampled locations. We found that Ae. aegypti abundance was positively correlated with hot and dry conditions within densely populated locations, with mean abundance peaking in the 33rd to the 44th weeks of the year. Ae. albopictus abundance was positively correlated with cooler temperatures in higher socio-economic locations with lower human population density, with mean abundance peaking in the 19th to the 32nd weeks of the year. Our results suggest that the diversity of the Dallas-Fort Worth metroplex's environmental conditions enable Ae. aegypti and Ae. albopictus to exploit differential niche spaces, which has the potential to influence vector control strategies and disease prevention efforts.