COVID-19: The Brain and Nervous System
This week’s article will begin to discuss symptoms and conditions involving the brain and nervous system associated with COVID-19 . Many of the longer-term symptoms of COVID-19 are neurological or psychiatric in nature. I will continue discussion of these long-term neuropsychiatric consequences next week.
Information presented is intended to provide a medical perspective - the articles are not intended as a political statement for or against any public policy. Statements in these articles should be considered coming from myself, not from any organization I represent or my employer.
Most people who get infected with COVID-19 will have primarily respiratory symptoms and/or symptoms common to many other viral illnesses. However, a significant percentage of people will suffer from neurological symptoms. A number of conditions and symptoms related to the brain and nervous system have been seen in people with COVID-19.
We are still studying the mechanisms for why people are having nervous system problems from this virus. There are likely several mechanisms for how the virus directly or indirectly affects the nervous system.
SARS-CoV-2 enters our cells by attaching to and using a protein that spans the cellular membrane of cells in many tissues in our body. The protein called ACE2 is essential in a system that regulates blood pressure and fluid balance. ACE2 also protects organs from inflammatory injuries and has other functions. ACE2 is found on cells in the brain. The virus has been identified in cerebrospinal fluid and in autopsy brain samples. The virus may also have indirect effects on the nervous system. We know that people with COVID-19 can suffer from problems related to how the blood and blood vessels work. The virus directly or indirectly has been implicated in blood clotting and dysregulation of blood flow. When this happens in the brain it is not hard to imagine that it would affect the function of the brain. Other problems the virus causes in the brain may be related to inflammation, oxygen deprivation and disruption of the protective blood-brain barrier.
Short and long term neurological symptoms have been noted in people who have otherwise mild symptoms as well as in those who experience severe COVID-19. According to the Infectious Disease Society of America, neurologic complications are common in hospitalized patients with COVID-19.
In those with severe COVID-19 a number of neurological problems have been seen including impaired consciousness, stroke, seizure, meningitis, encephalopathy and Guillain-Barré syndrome.
Encephalopathy is one of the most common neurologic problems reported in hospitalized COVID-19 patients. Different studies have found this condition present in various percentages. One larger study of critically ill patients found that over 30% had encephalopathy. Encephalopathy is a general term that describes a diseased or damaged brain that is not functioning well. The term is generally reserved in cases where there is at least moderate dysfunction of the brain.
People with COVID-19 are at risk of having blood clots. Because of this, stroke would be expected to be a possible complication of COVID-19. Stroke, while not common in covid, appears more likely to be seen in people with COVID-19 than with influenza. In one study it was found that stroke occurred 7.6 times more often in people with COVID-19 than influenza. Fortunately, stroke has only been rarely seen in very young people with COVID-19 however there are numerous case reports of otherwise healthy people in their 30’s, 40’s and 50’s suffering a major stroke during or after their COVID-19 illness.
A study released in the journal Stroke found a higher rate of young and healthy stroke victims during the pandemic compared to averages before the pandemic began. The researchers in 136 hospitals across 32 nations found that some 25% of stroke patients who had also been sick with COVID-19, were under the age of 55, as compared to only 10-15% percent of stroke patients in that age group prior to the pandemic. They also found that aside from being COVID-positive some 25% of the stroke patients studied had no other obvious risk factors for stroke such as high blood pressure, diabetes or smoking. Many of the stroke victims had otherwise asymptomatic COVID-19.
Children are not being spared from neurological consequences of being infected with SARS-CoV-2. A study published on December 21, 2021 in the journal Pediatric Neurology described neurological problems in kids being hospitalized for COVID-19. Of these hospitalized kids: 16% had encephalopathy, 7% experienced seizures and 0.9% suffered a stroke. A number of other neurological problems were reported such as coma, encephalitis, meningitis and dysautonomia (dysfunction of the autonomic nervous system).
Disturbances of the senses of taste and smell are common in adults and children with COVID-19. Often thought of as just minor symptoms, loss of these senses can have serious consequences. Loss of these senses has been seen as a persistent problem in many people weeks and months after having COVID-19. Next week I will further discuss this and other long-term consequences of COVID-19.
Update on Vaccines
Last week a second COVID-19 vaccine was granted full FDA approval. The “Moderna vaccine” now has full FDA approval and licensure and may be given to people 18 years and older. The brand name for this vaccine is Spikevax. Last August FDA approval was granted for the vaccine manufactured and distributed through a partnership between the biotechnology company BioNTech and Pfizer (brand name = COMIRNATY). The vaccine developed by Janssen Pharmaceuticals which is owned by Johnson & Johnson continues to be given to people 18 years and older under the FDA’s Emergency Use Authorization.
Multiple medical organizations recommend that everyone 5 years and older get vaccinated against COVID-19. For children aged 5-11 a lower dose of the Pfizer-BioNTech is authorized and comes in a different concentration and packaged in a different vial than the vaccine given to those 12 years and older. Parents should go to vaccines.gov to find a location that has the Pfizer-BioNTech vaccine for their children ages 5 through 11.
Booster doses are recommended for ages 12 and up. Booster doses are available for all three of the COVID-19 vaccines. For those who have completed the primary 2 shot series with the Pfizer-BioNTech or Moderna vaccine - they should have a booster dose 5 months after the second shot. A booster dose should be given to everyone who has had a primary vaccination with the Johnson and Johnson vaccine at 2 months with any of the 3 vaccines. Additional vaccine doses are also given to those who have problems with their immune system.
Last week Pfizer-BioNTech applied for Emergency Use Authorization to use the vaccine for children 6 months old through age 4. Also last week the biotechnology company Novavax, Inc. submitted a request to the FDA for Emergency Use Authorization for the vaccine they have been developing.
Russ Coash, PA-C
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