Project Summary Aedes aegypti mosquitoes are primary vectors of dengue, yellow fever, and the newly emerged threats of Zika and chikungunya viruses. In recent years, mosquito-borne diseases have reemerged as a pressing public health issue around the world, as the geographic range of mosquitoes has increased rapidly due to expanded global trade and travel and potentially due to increased temperatures caused by climate change. Maricopa County, Arizona is potentially at risk for developing Ae. aegypti transmitted diseases due to the established presence of the mosquito vector and the high volume of travelers coming to Arizona from areas with endemic Ae. aegypti- borne disease. In fact, on average, over 25 million travelers cross the border from Mexico (an area with diseases transmitted by the vector) into Arizona each year. Although much research exists on the wide-scale distribution of mosquito vectors, there is less understanding of the local factors that promote mosquito populations or the geographic range of the mosquitoes, especially in a desert climate. It is not known whether there are local socioeconomic or environmental characteristics that support larger Ae. aegypti populations or how mosquitoes move between local populations. We will use a combination of statistical analysis, spatial analysis, and phylogenomic analysis to develop a better understanding of the local factors that support mosquito populations and how mosquito populations are moving over time and space. The long-term goal of this project is to identify small-scale socioeconomic or landscape characteristics that consistently support Ae. aegypti populations and implement interventions with the Vector Control Division in Maricopa County, AZ to reduce mosquito populations, thereby reducing disease transmission risk. The rationale for this application is that the understanding of the distribution, range, and movement of the mosquito populations is a critical component of implementing effective public health efforts that can reduce disease burden and cost by aiming to prevent potential outbreaks of mosquito-borne disease. Hypothesis: Ae. aegypti will not be uniformly distributed throughout Maricopa County, with some areas having larger populations due to differences in infrastructure or landscape characteristics (which are related to neighborhood socioeconomic status) and therefore potential mosquito habitat. Furthermore, we hypothesize that genetically distinct populations will be separated by short distances and will be unique to specific neighborhoods. Aim 1: Characterize the neighborhood socioeconomic factors associated with Ae. aegypti abundance. Aim 2: Characterize landscape traits, such as greenness, that are associated with Ae. aegypti populations. Aim 3: Characterize the origin of and migration between local Ae. aegypti mosquito populations within Maricopa County, Arizona.