A positive COVID-19 rapid antigen test. (IMAGE) PLOS Caption A positive COVID-19 rapid antigen test. Credit Rod Long, Unsplash, CC0 (https://creativecommons.org/publicdomain/zero/1.0/) Usage Restrictions No restrictions. License CC0 Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.