Nearly a third of people with COVID-19 experience symptoms up to nine months after their diagnosis, even if they initially had a mild case, a small new study indicates.
Researchers from the University of Washington analyzed the information from 177 people in the Seattle area with confirmed COVID-19 infections that followed three to nine months after their diagnosis. (The average follow-up time was six months.) Most participants – 150 people, or 85% of the study group – had a mild case of COVID-19 and were not admitted to hospital; 11 participants (6%) were asymptomatic; and 16 participants (9%) were admitted to the hospital.
Overall, 32.7% of patients with mild cases and 31.3% of hospital patients said they had at least one persistent symptom that persisted for at least three months after diagnosis.
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The most common persistent symptoms were fatigue, which was generally reported by 13.6% of participants, and loss of smell or taste, which was also reported by 13.6% of participants, the authors said. About 13% of participants experienced other persistent symptoms, including muscle aches, breathing problems, cough, and brain fog.
“Our research indicates that the health consequences of COVID-19 go far beyond acute infection, even among those who experience mild illness,” the authors wrote in their paper, which was published in the journal on Friday (February 19). JAMA Network open.
The authors also asked participants about their quality of life after being infected, and 30% of participants reported a poorer quality of life compared to before their infection, including 8% who reported problems with daily tasks, such as tasks.
“What is clear is that you can initially do well, but then over time develop symptoms that are very crippling in terms of fatigue,” studies senior author dr. Helen Chu, Associate Professor of Medicine, Division of Allergy and Infectious Diseases, at the University of Washington School of Medicine, said in a statement.
The study is one of the longest follow-up of people with COVID-19. However, the study was limited because it included a relatively small number of participants from one place. Yet, with millions of cases worldwide, ‘even a small incidence of long-term weakness can have enormous health and economic consequences’, the authors wrote.
Exactly why some people develop these persistent symptoms – sometimes called “lank COVID“- is unclear.” Is it some kind of immune activation, some kind of infection or the development of autoimmunityasks Chu, who added in the statement that she and her colleagues are going to analyze blood samples from patients with COVID-19 to study this question.
Originally published on Live Science.