Throughout the entire last year, the effects of COVID 19 became abundantly clear. It was a respiratory virus that was highly contagious and damaged multiple organ systems. The rate of spread was fast. It was hard for public health and medical professionals to keep up with the devastation.
My blogs from over the past year have all been about aspects of COVID that caused emotional responses, from fear to anger. In January, a number of research articles were released that demonstrated the damage that COVID inflicted on our brains. This research is just coming out because the researchers had to ‘look’ at brains post-mortem. There wasn’t any other way to put all of the pieces together to figure out how the virus was acting. The news about the virus entering the brain sent chills throughout the medical community. And their fears were realized when the research reports were issued.
Indicators of Brain Involvement in Other Viruses
Dr. Gabriel A. de Erausquin, a professor of neurology at the University of Texas Health Science Center at San Antonio, notes that “Since the flue epidemic of 1917 and 1918, many of the flu-like diseases have been associated with brain disorders.”
“Those respiratory viruses included H1N1 and SARS-CoV. The SARS-CoV-2 virus, which causes COVID 19, is also known to impact the brain and nervous system,” adds the researcher. The question now becomes – how, and to what extent?
Initial Effects on the Brain
Dr. de Erausquin recently published a study along with his colleagues, including senior author Dr. Sudha Seshadri, a professor of neurology at the same institution and director of the university’s Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases.
Their basic premise was that the respiratory viruses have an affinity for nervous system cells. Prof. Seshadri explains, “Olfactory cells are very susceptible to viral invasion and are particularly targeted by SARS-CoV-2, and that is why one of the prominent symptoms of COVID-19 is loss of smell.”
Olfactory cells are concentrated in the nose. Through these cells, the virus reaches the olfactory bulb in the brain, which is located near the hippocampus, the center of learning and memory. “The trail of the virus, when it invades the brain, leads almost straight to the hippocampus,” explains Dr. de Erausquin. “That is believed to be one of the sources of cognitive impairment observed in COVID-19 patients.” And this is a very somber statement, “We suspect it may also be part of the reason why there will be an accelerated cognitive decline over time in susceptible individuals.”
What Ways Does Coronavirus Affect the Brain?
Cases around the world show that patients with COVID-19 can have a variety of conditions related to the brain, including:
· Confusion
· Loss of consciousness
· Seizures
· Stroke
· Loss of smell and taste
· Headaches
· Trouble focusing
· Changes in behavior
Patients are also having peripheral nerve issues, such as Guillain-Barre` syndrome, which can lead to paralysis and respiratory failure.
“Once it infects the brain, it can affect everything”
Scientists analyzed levels of the virus in several organs, comparing the intervention group of mice with a control group. The results showed that the viral levels in the lungs peaked around day 3 after the infection, but levels in the brain persisted on days 5 and 6, coinciding with the symptoms being the most severe and debilitating. The scientists also found that the brain contained 1,000 times higher levels of the virus than other parts of the body.
One of the senior researchers, Kumar, stated that, “Our thinking that [COVID-19] is more of a respiratory disease is not necessarily true. Once it infects the brain, it can affect anything because the brain is controlling your lungs, the heart, everything. The brain is a very sensitive organ. It’s the central processor for everything.”
The Findings of the National Institute of Health
The National Institute of Neurological Disorders and Stroke conducted extensive in-depth examinations of human brain tissue samples. Their findings, published in the New England Journal of Medicine, suggest that COVID-19’s many neurological symptoms are likely explained by the body’s widespread inflammatory response to infection and associated blood vessel injury – not by infection of the brain tissue itself.
The team focused on the brain’s olfactory bulb that controls our ability to smell and the brainstem, which regulates breathing and heart rate. As I mentioned earlier, both of these regions are highly susceptible to COVID-19.
Potential Outcomes of COVID-19 Infection
The brain is one of the regions where viruses like to hide. Unlike the lungs, the brain is not as equipped, from an immunological perspective, to clear viruses. That’s why we’re seeing severe disease and all these multiple symptoms like heart disease, stroke, and all these long haulers with loss of smell, loss of taste. All of this has to do with the brain, rather than the lungs. (https://www.medicalnewstoday.com)
Senior Researcher Kumar, cautions that the brain damage may mean that many people with COVID-19 continue to be at a high risk of neurodegenerative diseases, such as Parkinson’s, multiple sclerosis, or general cognitive decline, after recovering.
Unfortunately, it appears that many people who had COVID-19 will face a very uncertain cognitive future.
References:
Collins, F. (January 14, 2021). Taking a closer look at COVID-19’s effects on the brain. Retrieved from https://directorsblog.nih.gov/2021/01/14/taking-a-closer-look-at-the-effects-of-covid-19-on-the-brain
Sandoiu, A. (January 25, 2021). COVID-19 and the brain: what do we know so far? Retrieved from https://www.mwdicalnewstoday.com/articles/how-does-sars-cov-2-affect-the-brain#Once-it-infects-the-brain-it-can-affect-anything
