How the coronavirus reaches the brain

The coronavirus can also attack the brain and cause neurological deficits such as olfactory disorders to strokes why. Charité researchers have found a possible explanation for this.

It has long been known that many Covid 19 patients suffer from neurological symptoms such as loss of smell and taste. In addition to these long-lasting symptoms, a corona infection can apparently also have more serious consequences.

According to the German Society for Neurology (DGN), “diffuse brain damage can occur with neurological and psychiatric abnormalities, inflammation of the brain and spinal cord, or strokes.”

The funny thing is not only that COVID-19-Patients with cardiovascular risk career would suffer. A stroke can also occur in “vascularly healthy” young people.

Study: vast majority are not symptom-free after Covid-19

It is also worrisome that neurological symptoms often persist longer. This was demonstrated by a study from Italy, which was published in July in the English-language magazine “JAMA”. She examined whether and what symptoms persisted in the Covid 19 patients after they were discharged from the hospital. 87 percent of the patients showed symptoms later.

The most frequent neurological sequelae were according to this study

• Tiredness or fatigue, that is, persistent severe exhaustion (about 53 percent),
• Impaired sense of smell (about 16 percent),
• Taste disorders (about 11 percent),
• Headache (about ten percent),
• Dizziness (about five percent).

Headache: After a Covid-19 illness, some patients complain of persistent pain. (Source: NickyLloyd / Getty Images)

Berlin Charité study: how SARS-CoV-2 enters the brain

It is not clear how exactly the coronavirus can penetrate the brain. Experts in neuropathology, pathology, forensic medicine, virology and clinical care at the Berlin Charité have now published new findings in this regard in the specialized journal “Nature Neuroscience”.

Consequently, the coronavirus reaches the brain through the nerve cells of the olfactory mucosa directly from the nose. The olfactory mucosa is located in the superior turbinates, in the so-called roof of the nose on both sides of the superior nasal septum. It has around ten million olfactory cells, as explained by the German Professional Association of Otolaryngologists.

The research team surrounding Prof. Dr. Frank Heppner, Director of Neuropathology at Charité, examined 33 tissue samples from people who had died in connection with Covid 19 disease, on average at an age of almost 72 years. Using state-of-the-art methods, the scientists analyzed samples from the olfactory mucosa and four different brain regions.

The result: they were able to detect intact viral particles in various structures that connect the eyes, mouth and nose to the brain stem. The highest viral load was found in the olfactory mucosa. “On the basis of these data we assume that SARS-CoV-2 it can use the olfactory mucous membrane as a gateway to the brain, “according to one report. At the same time, according to the researchers, this explains the frequent disturbances of the sense of smell and taste in corona infections.

How does the crown spread from nerve cells?

However, the researchers note that the study only examined deceased Covid 19 patients who suffered a severe course during their lifetime. It cannot be transferred to medium or light courses.

It is also unclear how exactly the virus spreads from nerve cells. The research team assumes that it migrates “from one nerve cell to another” to reach the brain. However, transport through the blood vessel system is also possible, as the study data shows. Likewise spread too Herpessimplex virus or the rabies virus that causes rabies.