Acknowledgments
This work was supported by the US Centers for Disease Control and Prevention (Cooperative Agreement 1 U01 CK000337-01 to DATC), and the Engineering and Physical Sciences Research Council (grant EP/N014499/1 to JMR). We would like to thank the Allegheny County Department of Health (Dr. Luanne Brink and Steve Forest) for providing their data; and the schools, staff, students, and parents who participated in PIPP, SMART, and SMART2. We also thank Rahaan Gangat of the National Weather Service Pittsburgh for his assistance with climate data. We thank Scott Zeger for helpful discussions regarding analyses.