(CNN) — Dr. Anthony Fauci got into a contentious exchange with Sen. Rand Paul (R-KY) Thursday over whether people should wear masks if they have recovered from Covid-19 or been vaccinated against it.

Paul, who says he has been infected with coronavirus and who <a href="http://www.cnn.com/2021/02/10/politics/rand-paul-mask-senate-impeachment-trial/index.html" target="_blank">pointedly refuses to