Reports from the United Kingdom suggest that a common COVID-19 symptom has returned for the omicron variant — brain fog.

The Daily Express — a news outlet in the U.K. — recently reported that COVID-19 patients have been reporting “brain fog” as one of their symptoms in the ZOE COVID Study app, which records and analyzes symptoms as reported by patients.

  • “One of the more unusual — but surprisingly common — symptoms of Omicron is so-called brain fog,” The Daily Express reports.
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Brain fog has been a somewhat rare COVID-19 symptom for quite some time now. In fact, reports of brain fog emerged in October 2020, well into the first year of the pandemic, as I wrote for the Deseret News. But it is not often reported as one of the more common symptoms, which includes fever, chills, shortness of breath, coughing and body aches.

Dr. Shruti Agnihotri, a neurologist at the University of Alabama Birmingham, told ABC 33/40 that brain fog is often associated with severe headaches and memory loss.

  • “Often times these patients may have even recovered from the initial fever and shortness of breath symptoms and they continue to have very severe headaches and tend to often complain about memory loss, often referred to as a brain fog.”

Brain fog may resemble a concussion, she said.

  • “Patients often times describe difficulty with attention, focus, just not feeling right, not as sharp as they have otherwise been. We sometimes see these symptoms in many other conditions, during post-concussion, and we also see them after various other infections too,” Agnihotri told ABC 33/40.

The symptom has now emerged with the omicron variant, and is another clue into how the omicron variant will impact people moving forward.