We combined field-based data with mathematical modeling to estimate the effectiveness of smartphone-enabled COVID-19 exposure notification in Pennsylvania, USA. We estimated that digital notifications potentially averted 7-69 cases/1,000 notifications during November 8, 2020-January 2, 2021. Greater use and increased compliance could increase the effectiveness of digital notifications.
Keywords: COVID-19; Pennsylvania; SARS; SARS-CoV-2; United States; cases averted; coronavirus; coronavirus disease; digital exposure notification; respiratory infections; severe acute respiratory syndrome coronavirus 2; viruses; zoonoses.