SUMMARY - Detection of blood–brain barrier disruption in brains of patients with COVID-19, but no evidence of brain penetration by SARS-CoV-2

This study looked at how COVID-19 affects the brain, particularly focusing on whether the virus can enter the brain and cause damage. Researchers examined the brains of individuals who had died after COVID-19 infection, as well as controls who had no COVID-19 or neurological diseases. They found no evidence of the virus in the brain tissue, suggesting that SARS-CoV-2 (the virus that causes COVID-19) may not directly infect the brain. However, they did observe significant damage to the blood-brain barrier (BBB), which protects the brain from harmful substances. This BBB disruption was seen in all patients with COVID-19, suggesting it could play a role in the brain-related symptoms seen in COVID-19 survivors, like "brain fog" or long-lasting cognitive problems. The study calls for more research to understand how this damage to the BBB might contribute to these neurological symptoms.