Infectiousness of SARS-CoV-2 breakthrough infections and reinfections during the Omicron wave
Sophia T. Tan, Ada T. Kwan, Isabel Rodríguez-Barraquer, Benjamin J. Singer, Hailey J. Park, Joseph A. Lewnard, David Sears & Nathan C. Lo
Nature Medicine (2023)
... we show that both vaccine-derived and naturally acquired immunity independently reduce the infectiousness of persons with Omicron variant SARS-CoV-2 infections in a prison setting. Analyzing SARS-CoV-2 surveillance data from December 2021 to May 2022 across 35 California state prisons with a predominately male population, we estimate that unvaccinated Omicron cases had a 36% (95% confidence interval (CI): 31–42%) risk of transmitting infection to close contacts, as compared to a 28% (25–31%) risk among vaccinated cases.