New research from the National Institutes of Health identified "clear objective changes" in people with postinfectious myalgic encephalomyelitis/chronic fatigue syndrome.
Chronic fatigue syndrome is something of a mystery to modern medicine; researchers don’t know what causes it, most doctors don’t learn about it in medical school, and it goes undiagnosed in around 90 percent of cases.
Some long COVID researchers have suspected smaller, less obvious blood clots may be causing many of the puzzling symptoms reported by patients who have lasting effects of the virus.