SARS-CoV-2 Breakthrough Infections in Fully Vaccinated Individuals

Abstract

Importance: While COVID-19 vaccines are highly effective against disease, breakthrough infections may occur in the context of rising variants of concern. Objective: We paired random and passive surveillance nucleic acid testing with analysis of viral whole genomic sequences to detect and describe breakthrough infections, focusing in a university community. Design: Anterior nasal swabs were collected from individuals for a nucleic acid amplification test (NAAT) for detection of SARS-CoV-2. A subset of NAAT positive samples was sequenced to determine variants associated with infections. Included in the testing and sequencing protocol were individuals that were fully vaccinated. Setting: This study was performed as part of a surveillance program for SARS-CoV-2 on a university campus with 49,700 students and employees. Participants: Surveillance testing was random and included approximately 10% of the population each week. Additionally, individuals self-identified with COVID-19 related symptoms or those that had close contact with SARS-CoV-2 positive individuals were also tested.