Can vaccines help long-haul COVID-19 sufferers?

While most people who contract COVID-19 test negative for the virus and recover weeks after infection, an undetermined percentage of people who also test negative continue to report symptoms for months on end. Testimonies from people in this group, known as COVID "long-haulers," who say they found relief after receiving the vaccine, have offered a new clue into the ongoing mystery of so-called "long COVID."

"This is real, this is not imaginary. These are people whose symptoms are real," Dr. Anthony Fauci said of long COVID at a Senate hearing on Wednesday. The director of the U.S. National Institute of Allergy and Infectious Diseases said anywhere from 25% to 40% of individuals who test positive for COVID-19 "have prolongation of symptoms that measure not only in weeks, but in months," some of which, he added, "become completely incapacitating." Long COVID commonly manifests as persistent severe fatigue, difficulty with thinking and concentration, known as "brain fog," a heart rate that speeds up with no activity, severe exhaustion despite limited activity, loss of smell and taste, pain like pins and needles in the hands and feet, and an array of other symptoms, according to Dr. Jason Maley, program director of the Critical Illness and COVID-19 Survivorship Program at Beth Israel Deaconess Medical Center in Boston.