High Community Transmission of SARS-CoV-2 Associated with Decreased Contact Tracing Effectiveness for Identifying Persons at Elevated Risk of Infection – Vermont

Abstract

Vermont contact tracing (CT) consistently identified people at risk for COVID-19. However, the prevalence ratio (PR) of COVID-19 among contacts compared with noncontacts when viral transmission was high (PR = 13.5; 95% CI: 13.2–13.9) was significantly less than when transmission was low (PR = 49.3; 95% CI: 43.2–56.3).