ABSTRACT

Objectives. To evaluate equity in wastewater-based infectious disease surveillance, including equity of inclusion, outbreak detection, and disease forecasting.

Methods. We assessed New York State’s wastewater surveillance network using census tract–level data to compare social vulnerability and environmental burden across included, sewered but excluded, and unsewered communities during the scale-up of the network (2020–2024) and under changing coverage scenarios. We modeled outbreak detection equity by estimating outbreak sizes required for 95% confidence in the detection of hypothetical pathogens and assessed forecasting equity using county-level COVID-19 hospitalization predictions in relation to population size, coverage, and vulnerability.

Results. We found similar vulnerability distributions between included and sewered but excluded communities. The 25% most vulnerable communities required median outbreak sizes 3.45 times larger for detection than did the 25% least vulnerable. At medium sensitivity, more than 80% of individuals living in poverty and minoritized populations lived in areas where outbreaks exceeded 10 infections before detection. Forecasting accuracy was lower in smaller (< 20%) than in larger urban (> 60%) counties and increased with population size and network coverage (P < .001).

Conclusions. Wastewater surveillance was equitable in population coverage but not in outbreak detection and forecasting performance.

Public Health Implications. Strategies such as upstream sampling, expanded wastewater treatment plant participation in smaller communities, and improved modeling for low-population areas may reduce inequities and enhance the utility of wastewater surveillance. (Am J Public Health. Published online ahead of print May 21, 2026:e1–e9. https://doi.org/10.2105/AJPH.2026.308472)