What if Covid-19 also had an impact on the brain in positive cases? The question arises as doctors in New York treating patients with the new coronavirus increasingly observe that with fever, cough and shortness of breath, another symptom appears. Indeed, some are confused, to the point of not knowing where they are, or what the current year is.
This loss of bearings is sometimes linked to lack of oxygen in the blood, but in some patients the level of confusion seems to be out of proportion to the level of affection in their lungs. According to Jennifer Frontera, a neurologist at Langone University Hospital in Brooklyn, the question ofimpact of the new coronavirus on the brain and nervous system must arise.
Studies are beginning to describe this phenomenon. In the journal of the American Medicine Association (Jama) last week, doctors reported that 36% of 214 Chinese patients had neurological symptoms, ranging from loss of smell to nerve pain, to seizures and strokes (Stroke).
In the New England Journal of Medicine, top rated American medical journal, French doctors in Strasbourg described that more than half of 58 intensive care patients were confused or agitated. Brain scanners even revealed possible inflammations.
Many viruses affect the brain
Virologists are not not totally surprised that the new coronavirus, SARS-CoV-2, may affect the brain and nervous system, as this link has been observed with other viruses, including the AIDS virus, HIV. Viruses can affect the brain in two main ways, explains Michel Toledano, neurologist at the Mayo Clinic in Minnesota.
The first is by triggering an abnormal immune response called “cytokine storm”, which causes inflammation of the brain, this is called autoimmune encephalitis. The second is by direct brain infection, known as viral encephalitis. The brain is protected by what is called the blood-brain barrier, whose role is to block intruding substances.
However, this can be broken and some hypothesize that the nose could be the path to the brain, since loss of smell is common to many Covid-19 patients. But this is not verified, and many patients who lose their sense of smell have no neurological problems serious.
Scientists remain cautious
The main track is actually that of the overheated immune response. To find out, the virus should be detected in the cerebrospinal fluid. It was done once, at a 24 year old Japanese, the case of which was described inInternational Journal of Infectious Disease.
He suffered from confusion and convulsions and brain imagery showed inflammation. But the test is not yet validated and the scientists remain cautious. To unravel these mysteries, Jennifer Frontera is collaborating on an international research project aimed at standardizing data collection.
His own team has recorded cases of seizures in Covid-19 patients who had never done it before getting sick. The researchers also observed tiny cerebral hemorrhages called “unprecedented”. Samples, like MRI scans, are difficult to take from patients on an artificial respirator because the majority die. Neurological damage is therefore difficult to study.
Those who survive, however, end up consult neurologists“We see a lot of patients in confused states,” said Rohan Arora, a neurologist at Long Island Jewish Forest Hills Hospital, AFP. He affirms that 40% of survivors of the coronavirus are affected by this phenomenon.
