Ask the Expert: What’s New in the Search for a Long COVID Cure?

UCSF infectious disease specialist Michael Peluso, MD, who co-leads one of the world’s oldest studies of long COVID, discusses the condition’s mysteries. “There is no smoking gun,” he says. “If that were the case, we would have figured this out two years ago.”

What exactly is long COVID?

“It refers to unexplained symptoms that are new or worse since someone had acute COVID and that are not attributable to other causes. They persist for at least three months after COVID’s onset and impact a person’s quality of life. Between 15 million and 30 million Americans may have it.

But there is not just one long COVID syndrome. Some people have profound neurocognitive symptoms, including difficulty concentrating. Others have cardiopulmonary symptoms that reduce their capacity to exercise. Others have disorders in their autonomic nervous system, with unexplained swings in their heart rate or blood pressure. And these categories are not monolithic. People can have symptoms across the categories.

I don’t think anybody believes a single pathological mechanism causes all cases of long COVID. It’s likely that different types of long COVID have different drivers.”