Americans are facing a roughly $3.7 trillion drag on its economy because of the long-haul effects of the nearly 100 million COVID-19 infections on top of the one million lives taken away by it, a Harvard economist predicted, CNBC reported on Wednesday.

David Cutler, an economist at Harvard University, said long COVID is a $3.7 trillion drag on the U.S. economy – about 17 percent of the country's pre-pandemic economic output, rivaling the cost of the Great Recession.

Long COVID refers to the mixed health complications after the COVID-19 infection that are still hard to test or diagnose to date. It usually comprises a variety of symptoms, including fatigue, breathlessness and cognitive dysfunction – confusion, forgetfulness or a lack of mental focus and clarity. 

Numerous reports have suggested that the number of people suffering from long COVID will only increase as infections grow.

The huge group affected by this "could be game-changing in terms of how we do medical practice in the same way HIV/AIDs was a game-changer," according to Doctor Peter Hotez, co-director of the Center for Vaccine Development at Texas Children's Hospital and a dean at Baylor College of Medicine.

Culter's report in July estimated that the medical spending for people with long COVID accounts for $528 billion of the total cost, and lost earnings and reduced quality of life would cost Americans $997 billion and $2.2 trillion, respectively.

Even such an estimation is conservative. "It is based on the 80.5 million confirmed U.S. COVID cases at the time of the analysis and doesn't account for future caseloads," CNBC said.

"Long COVID will be around long after the pandemic subsides, impacting our communities, our health care system, our economy and the well-being of future generations," said a November report by the Health+ program under the U.S. Department of Health and Human Services.