If Covid-19 acts like other coronaviruses, “it likely isn’t going to be a long duration of immunity,” Fauci, director of the National Institute of Allergy and Infectious Diseases, said during an interview Tuesday evening with JAMA Editor Howard Bauchner.

“When you look at the history of coronaviruses, the common coronaviruses that cause the common cold, the reports in the literature are that the durability of immunity that’s protective ranges from three to six months to almost always less than a year,” he said. “That’s not a lot of durability and protection.”

The National Institutes of Health has been fast-tracking work with biotech firm Moderna on a potential vaccine to prevent Covid-19, which has infected more than 6.28 million people worldwide and killed at least 375,987, according to data compiled by Johns Hopkins University.