2024 No https://doi.org/10.1016/j.scitotenv.2024.178217 Solo-Gabriele, Helena M. North America Observational Epidemiology Study Exposure Study Students Elementary (K-5) Middle/Jr High (6-8) High School (9-12) Viruses Absenteeism COVID rates COVID-19 SARS-CoV-2 Illness-related school absenteeism Wastewater Wastewater-based surveillance A study of nine U.S. schools monitored wastewater SARS-CoV-2 and absenteeism over 18 months. Higher viral loads, especially in enclosed schools, correlated with increased absences, supporting wastewater monitoring as a school health indicator.