The world has seen a pandemic of coronavirus (COVID-19) infection causing respiratory illness, but researchers are now trying to understand how the disease attacks the nervous system of some infected patients.

While symptoms such as fever, cough and breathing difficulty can be managed in most patients, scientists and medical professionals across the globe have recently documented several neurological issues, including stroke and encephalitis in some COVID-19 patients.

COVID-19 Virus and Neurological Symptoms

The SARS-CoV-2 virus mainly targets the respiratory system, but various studies have been done on the links between COVID-19 and neurological symptoms. The virus can infect the nervous system and affect the brain and spinal cord.

A group of researchers in Wuhan, China, found that about 36% of COVID-19 patients had neurological symptoms like headache, altered consciousness levels, and nerve pain. The COVID-19 virus activates a protein called ACE2 that is located on the surface of cells in the lungs, heart, kidney, intestine and brain and creates inflammation. It is believed that this inflammation is also contributing to neurological damage.

Similar cases of neurological symptoms were observed in Italy and Spain.

Encephalitis and COVID-19

Encephalitis, an inflammation of the brain, has been one of the neurological diseases that have been linked to COVID-19.

A group of researchers from the United Kingdom reported that a rare and severe form of brain inflammation, known as acute disseminated encephalomyelitis (ADEM), had been observed in a cluster of eight children in the UK. At least seven of them had COVID-19 symptoms or had been exposed to someone with the virus. In another study, a 58-year-old man was found to have meningitis, due to COVID-19, which made him experience seizures and confusion.

Infection and Impact on Central Nervous System

The COVID-19 virus can directly attack the central nervous system (CNS), which includes the brain and spinal cord. Studies have found viral RNA in the cerebrospinal fluid of some patients, indicating that the virus has invaded the CNS.

This invasion of virus in the CNS could lead to various neurological disorders, including dementia, which may not show symptoms until years after the infection.

COVID-19 and Increased Risk of Stroke

Stroke is caused by disruption in the blood supply to the brain. Studies of COVID-19 patients in China, Italy and the US showed patients were at an increased risk of stroke.

This is linked to several factors, such as the virus’s tendency towards hypercoagulability or elevated clotting, which is what makes people at risk for heart attack or blood clots. Inflammation in the blood vessels can cause constriction, which may increase the risk of stroke. COVID-19-induced hypoxia, or low oxygen levels, can also cause injury to the brain, making a stroke more likely.

Stroke can lead to varying signs and symptoms such as numbness, facial asymmetry, vision problems, and difficulty speaking and understanding speech.

COVID-19 and Guillain-Barré Syndrome

Guillain-Barré Syndrome (GBS) is an immune system disorder in which the body’s immune system attacks its own nervous system.

GBS can develop after an infection with bacteria or viruses such as Zika virus, Ebola virus, cytomegalovirus (CMV), and HIV. There is considerable evidence suggesting that COVID-19 infection may also trigger Guillain-Barré syndrome. A few COVID-19 patients who entered acute respiratory distress syndrome (ARDS) developed symptoms of GBS within the following few days.

GBS symptoms include muscle weakness or paralysis which may gradually worsen to include breathing problems and require hospitalization.

Possible Reasons for Coronavirus Impact on the Nervous System

The novel coronavirus binds to ACE2 receptors, which are found on most human tissues, and enters the cells.

It triggers an inflammatory response in the body, causing the immune system’s overreaction which leads to decreased oxygen supply and impaired blood flow to different organs, including the brain, as well as the formation of blood clotting in the blood vessels, which can lead to strokes. Also, the coronavirus can directly attack nerve cells in the brain, spine, and other regions of the CNS, which can cause neurological issues.

The presence of inflammation shows that the virus triggers a broad range of immune responses that may be responsible for the development of neurological disorders.

Prevention and Treatment of Neurological Issues Associated with COVID-19 Infection

Prevention of neurological issues linked to COVID-19 infection involves taking measures to prevent infection by practicing social distancing, hand hygiene, wearing masks and being vaccinated.

Patients in the hospital are also given blood thinners to avoid stroke and D-dimer tests which detect blood clots.

Other treatments for neurological problems may include corticosteroids, antiviral drugs, immunoglobulin therapy to boost the immune system, and plasmapheresis, a blood filtering process in which harmful antibodies are removed from the plasma to reduce inflammation. Symptomatic treatments such as seizures and headache can be done based on patient symptoms.

Conclusion

COVID-19 has been shown to cause various neurological disorders, such as encephalitis, meningitis, stroke, and Guillain-Barré syndrome, which highlights the need for a deeper understanding of the impact of COVID-19 on the nervous system.

While initial reports suggest that COVID-19 related neurological complications are less common than respiratory complications, the possibility of having neurological issues due to the COVID-19 infection is not currently being overlooked. Further research is required to understand the pathogenesis and clinical course of COVID-19 related nervous system disease, the better management of the disease, and the prevention of complications associated with the disease.