For years, long COVID has been defined almost entirely by what patients report feeling: fatigue, brain fog, memory lapses, a loss of motivation that won’t lift. Doctors have struggled to treat a symptom with no clear physical marker, and the condition has reshaped workplaces as employers scramble to accommodate it. But despite the shared symptoms, there’s been little for doctors to point to and say, “this is what changed in your body.”
Now, a new study from researchers at the Centre for Addiction and Mental Health and the University of Toronto may start to change that. Led by Jeffrey Meyer, a psychiatry professor at the University of Toronto, researchers used PET imaging to measure a protein called VMAT2, found on the nerve terminals that release dopamine, in 24 long COVID patients and 24 healthy people who’d had only mild or moderate initial infections.
