SAN FRANCISCO (KGO) -- One of the biggest medical mysteries about COVID-19 has been how some patients develop something called long haulers -- symptoms that include fatigue and confusion that can last for months.
A Bay Area virologist appears to have discovered the root cause, which is leading to better treatment and an end to suffering.
Caroline Stepovich has been a nurse for 37 years. Never had she run into so many skeptics that she had symptoms of long haulers.
"You're going to have to see a psychiatrist," she told ABC7 News. "You really believe you had COVID? You didn't. You really believe you had long haulers? You don't, and I will not see you unless you see a psychiatrist."
The Carmel resident had multiple negative results from nasal and antibody tests. That's until a Bay Area researcher, the former head of virology at Stanford, verified markers in her blood through advanced analysis.
"They're not in anyone's head. They're real," said Dr. Bruce Patterson, the CEO and founder of IncellDx in San Carlos. "They're due to real immunological abnormalities, and now we have ways of treating them."
Dr. Patterson used machine learning to zero in on a specific kind of white blood cell called monocytes.
"These cells were acting like a garbage can, and they were going around and scavenging dying cells that contained the COVID proteins and was reprocessing them so the immune system can see them," he explained.
The cells then trigger an inflammatory response that leads to chronic fatigue and brain fog, among many other symptoms.
"My brain fog was so severe that I would have to get up in the morning and make a list that I ate, that I took a shower, that I fed the dogs," said Stepovich.
Dr. Patterson's work on the root cause of long haulers is helping long suffering patients to be treated. Labs in Los Angeles and Chicago specialize in the analysis.
Stepovich acknowledges the development pulled her back from a dark place.
"The misery from it and that no one believes you and there's no help just make you feel like, why live?" she said.
Patterson projects that one in three COVID cases may develop into long haulers. So far, treatment can lead to improvement in two to four weeks. His research findings have been published in the journal "Frontiers in Immunology." He also provides information to patients and doctors here.
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