1. In this prospective cohort study, rapid coronavirus disease 2019 (COVID-19) antigen tests had optimal performance when asymptomatic participants were tested three times at 48-hour intervals. 2. Additionally, rapid antigen tests had an optimal performance for symptomatic participants when they tested two times at 48-hour intervals. Evidence Rating Level: 1 (Excellent) Study Rundown: At-home rapid
Coronaviruses infect animals, humans, and birds. Human coronaviruses, such as SARS, MERS, and 2019-nCoV cause respiratory distress and even death. The S protein is the infectious agent of the virus.