Screening for safe opening of universities under Omicron and Delta variants of COVID-19: When less is more (preprint)

ABSTRACT

ABSTRACT As new COVID-19 variants emerge, and disease and population characteristics change, screening strategies may also need to change. We develop screening guidelines for the safe opening of college campuses, considering COVID-19 infections/hospitalizations/deaths; peak daily hospitalizations; and the tests required. Our compartmental model simulates disease spread on a college campus under co-circulating variants with different disease dynamics, considering (i) the heterogeneity in disease transmission and outcomes for faculty/staff and students based on vaccination status and level of natural immunity; and (ii) variant- and dose-dependent vaccine efficacy. Using the Spring 2022 academic semester as a case study, we study various routine screening strategies, and find that screening the faculty/staff less frequently than the students, and/or the boosted and vaccinated less frequently than the unvaccinated, may avert a higher number of infections per test, compared to universal screening of the entire population at a common frequency. We also discuss key policy issues, including the need to revisit the mitigation objective over time, effective strategies that are informed by booster coverage, and if and when screening alone can compensate for low booster coverage.