School-informed risk calculator tool for reducing the spread of respiratory viral infection among school-aged children

School health staff need decision support for responding to respiratory viral outbreaks. Quantitative microbial risk assessment (QMRA) tools are an inexpensive and fast resource. Our objectives were to engage school districts to inform the development of a risk-based calculator tool, test the tool across hypothetical cases, and elicit feedback among school health staff. We administered an online survey for Kindergarten (K) - Grade 5 teachers, school health professionals, and other school staff to gather data about respiratory viral disease interventions and model parameters. A risk calculator tool was developed in which users choose hypothetical scenarios to estimate infection risk per individual and compare interventions. Three case studies (CS) were explored: CS1 – Rhinovirus transmission in a general education classroom with "poor" vs. "great" air quality, CS2 – Influenza A virus transmission in a music classroom with vs. without a portable air purifier, CS3 – SARS-CoV-2 transmission in a special education classroom with vs. without open doors/windows. The prototype tool was presented at a national school nursing meeting, and attendees were surveyed on (dis)likes and anticipated tool uses. For the initial survey of Arizona school personnel (n = 132), the top respiratory viral outbreak strategies reported by teachers were hand (94 %) and surface hygiene (85.1 %). For all case studies, infection risks were above thresholds used in other contexts but were comparable to published student respiratory illness incidence data. At the national meeting, school nurses (n = 12) identified potential uses including advocating for interventions to administrators. This work reflects a unique application of community partnership and QMRA to address school health decision support.