September 25, 2023 – People with long COVID have specific biomarkers of their blood, in line with a study published Monday in Nature said.
The findings may very well be a step toward developing blood tests to obviously discover individuals with long COVID in order that specific treatments will be used, researchers said.
“This is a critical step forward in developing valid and reliable blood testing protocols for long COVID,” said David Putrino, PhD., lead writer and professor of rehabilitation and human performance and director of the Abilities Research Center at Icahn Mount Sinai Health System.
Researchers from the Icahn School of Medicine at Mount Sinai and Yale School of Medicine examined blood samples from about 270 people between January 2021 and June 2022. People had never been infected with COVID, had fully recovered from an infection, or were still showing symptoms no less than 4 months after infection.
Using machine learning, the research teams were able to tell apart between individuals with and without long COVID with 96% accuracy based on distinguishing features within the blood samples, in line with a Press release from Mount Sinai.
People with long COVID had abnormal T-cell activity and low levels of the hormone cortisol. Cortisol helps people feel alert and awake, which might explain why individuals with long COVID often report fatigue, NBC News said in a report on the study.
“It was one of the findings that most clearly separated the people with long Covid from the people without long Covid,” said Putrino NBC News.
The study also found that long COVID appears to reactivate latent viruses corresponding to Epstein-Barr and mononucleosis, the study said.
The blood tests could allow doctors to develop specific treatments for individuals who report a wide range of long-term COVID symptoms, Putrino said.
“There is no panacea for the treatment of long COVID as it is a disease that infiltrates complex systems such as the immune system and hormone regulation,” he said.
The CDC says about one in five Americans who've had COVID still have long COVID. Symptoms include fatigue, brain fog, dizziness, digestive problems, and lack of smell and taste.