At this point, life in the U.S. has largely returned to pre-pandemic normal. The COVID-19 public health emergency is over, mask mandates are mostly gone, and offices and schools are open again. But one hallmark of the pandemic remains in place: The U.S. Centers for Disease Control and Prevention (CDC) still directs anyone who tests positive for COVID-19 to isolate themselves from other people for at least five full days. Once those five days are up, the CDC recommends wearing a high-quality mask, such as an N95 or KN95, around other people when indoors for an additional five days.