How can we determine whether someone who has COVID-19 can transmit the virus to other people? Tests in routine clinical use, such as reverse-transcription polymerase chain reaction and antigen tests, are designed to determine whether SARS-CoV-2 is present or not, but many people have proposed that these tests be used to determine whether a patient is infectious. Furthermore, tests for SARS-CoV-2 that are not routinely used in clinical laboratories, such as viral culture and detection of sub-genomic viral RNAs, have also been discussed as indicators of infectivity. But how accurate are any of these tests for determining whether someone is infectious? Guest: Dr. Matthew Binnicker, Director of Clinical Virology and Professor of Laboratory Medicine and Pathology at Mayo Clinic. Twitter: @DrMattBinnicker Links: Can Testing Predict SARS-CoV-2 Infectivity? The Potential for Certain Methods to be a Surrogate for Replication-Competent Virus https://journals.asm.org/doi/10.1128/JCM.00469-21 Visit https://asm.org/jcm to read articles and/or submit a manuscript. Follow JCM on Twitter via https://twitter.com/JClinMicro Subscribe to ASM's YouTube channel at https://goo.gl/mOVHlK