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Your brain on COVID-19

Hands gesture at a tablet displaying brain scans.

Since the early days of the COVID-19 pandemic, researchers have suspected that the virus was affecting brain health. Many of the common symptoms—a bad headache, brain fog and a loss of the sense of smell—are neurologic, or connected to the brain. But scientists didn't yet have proof.

Now, a new report in the journal Nature offers evidence that the disease damages brain tissue and causes it to shrink.

Before and after

By reviewing before-and-after MRI brain scans of about 785 people in the United Kingdom who caught COVID-19 and comparing them to scans of those who didn't, the researchers found:

  • Decreased thickness and tissue contrast in some areas of the brain cortex. Such changes are often linked to worsening brain health.
  • Increased tissue damage in brain regions connected to the smell and taste systems.

The researchers found these changes to the brain even among patients who did not need to be hospitalized for COVID-19.

The report said more study will be needed to see if the effects are long-term or can be reversed.

More evidence

Other research has tracked COVID-19's damaging effect on the brain. According to a report from the National Institutes of Health (NIH), a review of health records from 3,744 Americans hospitalized with COVID-19 found that about 80% had neurological symptoms.

  • 49% had brain damage (encephalopathy).
  • 37% experienced bad headaches.
  • 26% had a loss of taste or smell.
  • 17% experienced coma.
  • 6% had a stroke.

The NIH is also building a national database to study links between COVID-19 and long-term health problems, including conditions like dementia and Alzheimer's.

Future risks

There's a lot more to learn about how COVID-19 affects the human body. And we don't know if the effects will be temporary or long-lasting. But emerging evidence shows clear harm to brain health.

Protect yourself and your loved ones by getting vaccinated. And stay up-to-date on the latest news about COVID-19 in our Coronavirus health topic center.

Reviewed 5/12/2022

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