CHICAGO -- When Linda Tomkow was diagnosed with COVID almost a year ago, she hoped for a quick recovery.
"I was aware of long COVID and I remember talking to my primary doctor, saying I hope I don't get long COVID, and I did," she said.
Other than the fever being gone, Tomkow's symptoms have never gone away. Initially, shortness of breath made it difficult for the 69-year-old retired physical therapist to even walk a short distance to the store.
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"I was very, very fatigued," she recalled. "I have a grocery store two blocks away from me and I took the bus the first time because I didn't think I would make it."
Her situation is far from unique. A large study, involving more than 270,000 patients in the U.S. and the United Kingdom, conducted by the University of Oxford found 1/3 of all COVID survivors experience at least one symptom three to six months after getting infected.
Doctors at Northwestern Medicine's Comprehensive COVID-19 Center said their long COVID patients experience symptoms even longer.
"We see people at nine months, a year, almost 18 months out after their COVID infection still having symptoms," said Dr. Marc Sala.
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Symptoms can include fatigue, shortness of breath, chest pain. Brain fog is among the most common.
"We all go in a room and forget why we went in and that's fine, but it happened to me like five times in 10 minutes," Tomkow said.
Because no one knows how long symptoms last, doctors say society must be prepared for the long-term impact on the economy and the health care system. While doctors expect long haulers to improve, for now they continue to deal with what they call a second pandemic.
Long haul COVID symptoms affect 1/3 of survivors, University of Oxford study finds