A report from the Centers for Disease Control and Prevention tracks wastewater samples collected across states and territories — including Tennessee — for concentrations of respiratory viruses such as influenza, RSV, and SARS-CoV-2. The CDC's National Wastewater Surveillance System (NWSS) aggregates that data and publishes trend lines that can serve as a leading indicator of community-level illness, often detecting rising viral loads days before clinical case counts reflect a surge.
Tennessee's contributions to the NWSS come through sampling sites tied to municipal wastewater treatment facilities distributed across the state's three grand divisions — West, Middle, and East Tennessee — with population centers such as Memphis, Nashville, Knoxville, and Chattanooga representing some of the largest catchment areas in the network. The Tennessee Department of Health coordinates with local utilities and the CDC to ensure samples are collected, processed, and uploaded to the national dashboard on a regular cadence.
Wastewater-based epidemiology has gained significant credibility since the COVID-19 pandemic demonstrated that viral RNA shed in sewage could signal outbreak trajectories before hospitals reported case increases. The CDC's current state-level dashboard allows the public and health officials to view whether viral signals in a given state's wastewater are rising, falling, or holding steady relative to recent weeks, though the agency notes that site coverage and sampling frequency vary by jurisdiction.
For preparedness-minded Tennesseans, the significance of this surveillance program extends into infrastructure dependability. Tennessee's wastewater systems — particularly older combined sewer systems in cities like Knoxville and portions of the Memphis metro — have historically faced capacity and maintenance pressures. The integrity of those systems directly affects the reliability of pathogen data flowing into the NWSS; a treatment plant offline after a flooding event on the Tennessee River or the Cumberland River is a plant not contributing surveillance data, creating gaps precisely when storm-related crowding or displacement might accelerate disease transmission. The Tennessee Department of Environment and Conservation (TDEC) oversees wastewater utility compliance statewide and would be the agency coordinating with the CDC if infrastructure disruptions threatened data continuity during a concurrent public health event.
