Title: Geospatial Analyses to Assess Population Demographics and Representativeness in Wastewater-Based Public Health Surveillance

Advisors: Dr. Helena Mitasova, distinguished faculty fellow and professor in the Department of Marine, Earth and Atmospheric Sciences

Abstract: Wastewater-based public health surveillance analyzes untreated wastewater to detect human pathogens, providing timely information about diseases circulating in a community. After expanding rapidly during the COVID-19 pandemic, it has become a nationwide system for monitoring common respiratory viruses and emerging threats such as measles. Despite its growing utility, populations included in wastewater surveillance remain poorly defined. We demonstrate how to create sewershed polygons to define the wastewater sample area. Then we use sewersheds to characterize wastewater-monitored populations and assess whether they are representative of broader populations. We found that in some states, wastewater-monitored populations reflect the statewide population, while in others, they include higher proportions of minorities and are more socially vulnerable, despite also having higher educational attainment and median household income. Connecting sewershed population information to wastewater data strengthens our ability to transform wastewater into public health action.