Observed Mask Wearing and Presence of SARS-CoV-2 in School Wastewater, San Diego County, CA, 2022

• DOI: 10.2105/ajph.2024.307925
• Publication Date: 2025-03-12T20:03:17Z
• Authors: Rebecca Fielding-...; Tommi Gaines; Ashkan Hassani; Tina Le; Vinton Omaleki; Marlene Flores; Araz Majnoonian; F. Carrissa Wijaya; Rob Knight; Smruthi Karthikeyan; Richard S. Garfein
• Keywords: Odds; 2019-20 coronavirus outbreak

Objectives. To test the association between directly observed school masking behaviors and presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in wastewater. Methods. We randomly sampled a subset schools participating translational study on effectiveness passive wastewater surveillance nonresidential K‒12 settings San Diego County. Trained observers conducted biweekly systematic observations March May 27, 2022. Results. The proportion individuals was significant predictor detecting SARS-CoV-2 (adjusted odds ratio = 0.91; 95% confidence interval 0.85, 0.99; P .034). For every 10% increase percentage who were fully masked, decreased by nearly 10%. Conclusions. Masking does not need to be perfect effective. Mask mandates are unlikely reimplemented US schools, but interventions that encourage moderate increases may have an important role play improving children’s health decreasing spread COVID-19 other diseases. ( Am J Public Health. 2025;115(4):519–527. https://doi.org/10.2105/AJPH.2024.307925 )