COVID-19 started as a serious threat to the lungs, but it’s become just as synonymous with brain issues throughout the pandemic. Now, a new study is revealing exactly how the virus damages the central nervous system. Researchers at Tulane University say even a mild COVID infection can leave lingering damage in a patient’s brain.
Previous studies have documented several cognitive issues like headaches, confusion, and “brain fog” during a COVID patient’s infection and in the months following — as a symptom of long COVID. Until now, however, scientists haven’t fully understood how the illness targets the brain.
The new study found severe brain inflammation and injury resulting from reduced blood flow or oxygen traveling to the brain. This included neuron damage and cell death. The team also discovered microhemorrhages (small bleeds) in the brains of nonhuman primates who died after a coronavirus infection.
To the research team’s surprise, even primates who did not suffer from severe respiratory disease showed the same damage in the brain.
“Because the subjects didn’t experience significant respiratory symptoms, no one expected them to have the severity of disease that we found in the brain,” says lead investigator Tracy Fischer in a university release. “But the findings were distinct and profound, and undeniably a result of the infection.”
COVID brain damage may lead to a more severe infection
Fischer has been studying brains for decades. After Tulane’s National Primate Research Center launched a COVID pilot program in early 2020, the study author started examining the brain tissue of several animals infected with coronavirus.
Fischer’s initial findings were so shocking that she spent the next year refining the results to make sure COVID-19 was truly responsible for this severe brain damage. Concerningly, these new findings are in line with those coming from human autopsies during the pandemic.
Study authors say this suggests that nonhuman primates can serve as a reliable model as scientists continue to explore how COVID-19 damages the human body.
The team also notes that neurological problems are some of the first symptoms people experience during a COVID infection. These symptoms also impact patients of all ages, whether they have pre-existing conditions or not.
As for how brain damage from COVID may impact a patient’s chances of survival, researchers say the brain plays a major role in controlling a person’s respiratory system — a main target of COVID.
“Neuropathological complications may contribute to worsening disease among infected patients. For example, damage to the brainstem, which modulates the respiratory cycle by regulating inspiratory and expiratory muscle activity, may contribute to worsening respiratory distress and failure in patients with COVID-19,” the researchers write in the journal Nature Communications.