Long-term Covid-19 symptoms "could be an issue," Fauci warns From CNN Health's Andrea Diaz Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, speaks during a White House press briefing in Washington, D.C., on January 21. Alex Wong/Getty Images Long-term Covid-19 symptoms should be taken seriously as they could be an issue as more people contract the virus, the top US infectious disease expert says. "This is a real phenomenon. I myself am personally dealing and helping a number of people who have a post-acute Covid-19 syndrome," Dr. Anthony Fauci told MSNBC's Rachel Maddow Friday. "They are virologically okay -- the virus is no longer identified in them, but they have persistence of symptoms that can be debilitating."