As of February 2022, the syndrome was estimated to affect about 16 million adults in the U.S. and had forced between two million and four million Americans out of the workforce, many of whom have yet to return. Long COVID often arises in otherwise healthy young people, and it can follow even a mild initial infection.
A meta-analysis of 41 studies conducted in 2021 concluded that worldwide, 43 percent of people infected with SARS-CoV-2 may develop long COVID, with about 30 percent—translating to approximately 30 million people—affected in the U.S. Some studies have offered more conservative numbers. A June 2022 survey reported by the U.S. National Center for Health Statistics found that among adults who had had COVID, one in five was experiencing long COVID three months later; the U.K. Office for National Statistics put the estimate at one in 10. Even if only a small share of infections result in long COVID, experts say, they will add up to millions more people affected—and potentially disabled.