RSV concentration in wastewater and trends among incident hospitalizations in children and older adults

Wastewater-based epidemiology (WBE) has the potential to fill gaps in clinical surveillance for respiratory syncytial virus (RSV) burden. Previous studies have shown RSV to be detectable in wastewater, but few have linked detections to clinical data because, in many locations, RSV is not a reportable disease. Further, studies that have linked RSV in wastewater to clinical data have not distinguished between pediatric and adult infections, as is common in studies of RSV. Using 2,662 influent wastewater samples collected from twenty-four treatment plants in four New York counties, we measured the RSV concentration in wastewater and compared levels detected to RSV hospitalizations from September 2022 to July 2024. RSV concentrations in wastewater correlated well with RSV hospitalizations ({rho} between 0.52 and 0.85, P <0.001). RSV concentrations in wastewater lagged hospitalizations for under 10-year-olds by an average of three weeks but were a leading indicator for hospitalizations in patients over 50 by up to two weeks. In predictive models, wastewater explained 88 percent of the variance in RSV hospital admissions among people over 50. Wastewater-based epidemiology of RSV is therefore a reliable surveillance method and could provide early warning for increases in RSV hospitalizations among older populations.