More than three years into the pandemic, the millions of people who have suffered from long COVID finally have scientific proof that their condition is real.
Scientists have found clear differences in the blood of people with long COVID — a key first step in the development of a test to diagnose the illness.
The findings, published Monday in the journal Nature, also offer clues into what could be causing the elusive condition that has perplexed doctors worldwide and left millions with ongoing fatigue, trouble with memory and other debilitating symptoms.
The research is among the first to prove that "long COVID is, in fact, a biological illness," said David Putrino, principal investigator of the new study and a professor of rehabilitation and human performance at the Icahn School of Medicine at Mount Sinai in New York.
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