New York: A new study shows that SARS-CoV-2 (a virus that causes Covid-19) may not directly infect the brain, but it may still cause serious neurological damage.
The findings, published in the journal Brain, indicate that the nervous system changes often seen in these patients may be caused by inflammation caused by the virus in other parts of the body or in the blood vessels of the brain.
“We’ve looked at more brains than other studies and we have used more techniques to search for the virus. The bottom line is that we find no evidence of viral RNA or protein in brain cells,” said researcher James E. Goldman from Columbia University.
In this study, the research team examined the brains of 41 Covid-19 patients who died of the disease during hospitalization. These patients are between 38 and 97 years old, about half of them have been intubated, and all have lung damage caused by the virus.
All patients underwent extensive clinical and laboratory examinations, and some patients underwent brain MRI and CT scans.
In order to detect any virus in brain neurons and glial cells, the researchers used a variety of methods, including RNA in situ hybridization, which can detect viral RNA in intact cells. Can detect antibodies to viral proteins in cells; RT-PCR, a sensitive technology for detecting viral RNA.
Despite in-depth research, researchers have not found evidence of the virus in patients’ brain cells. Although they did detect very low levels of viral RNA by RT-PCR, this is most likely due to viruses in blood vessels or the brain-covering leptomeninges.
The test was performed on two or more brain regions including the olfactory bulb. The search was conducted because some reports speculated that the coronavirus can enter the brain from the nasal cavity through the olfactory nerve.
“Even there, we didn’t find any viral protein or RNA. Though we found viral RNA and protein in the patients’ nasal mucosa and in the olfactory mucosa high in the nasal cavity,” Goldman said.