What initially was known to be just a respiratory disease, COVID-19 has shown highly diverse symptoms and after-effects over time. Amidst the ongoing studies and researches about the novel coronavirus, cases of neurological problems have come up. COVID-19 patients have been seen to present a variety of brain-related conditions such as confusion, unconsciousness, loss of taste and smell, inability to focus and the conditions have been as severe as strokes and seizures. Although, the data available as of now is very limited, here is what we know as per certain studies by doctors, scientists and various research organisations.
Effects Of COVID-19 On Brain And Nerves
We talked to Dr Sreekanth Vemula, Consultant Neurologist at Apollo Hospitals and Magna Neurology, Hyderabad and he says, “The novel coronavirus can act in multiple ways in the brain and the most common ways in which it affects are:
- Thrombosis
Thrombotic process, which means the formation of clots inside the blood vessels. Because the clots interfere with the blood flow, there can be changes inside the brain, i.e that part of the brain to which the blood supply is cut-off can undergo damage. This damage can also cause stroke - Stroke
The blood vessels themselves can be damaged and can lead to bleeding inside the brain. Bleeding can also cause as much as a stroke. This stroke, depending upon which part is blocked, can lead to weakness of a hand, a hand and leg, mouth, loss of speech or vision, deviation to one side, difficulty in walking, etc. Sometimes, severe bleeding can also lead to coma or death. - Cerebral Venous Thrombosis (CVT)
Not only can the patients have clots or blocks in the blood vessels, but also have it in the veins in the brian, leading to a condition called Cerebral Venous Thrombosis (CVT). It can present in the form of headaches, weakness of any part of the body, changes in awareness or sensorium, fits or even coma.
Other effects on the brain may include:
- Encephalitis, which means inflammation of the brain
- Encephalopathy is the disease of the brain, i.e. any problem affecting the brain as a whole. Because the brain functions are wholly disturbed, there can be mild to severe alteration of awareness.
- When it is mild, people are usually in a confused state
- When it is severe, people feel drowsy, sleep and are unable to be awake for a long time
- When it becomes very severe, they can go into comatose or coma state
- Seizures or brain fits, which can be on one side, both the sides or generalised. These fits can come either by themselves or be a part of other brain problems.
Surprisingly in COVID-19, people with no pre-existing condition like blood sugar, high blood pressure, high cholesterol level, family history of stroke, etc. are having strokes. It is seen that people are having strokes either when they are suffering from COVID-19 or some even had it a month after they had recovered from the novel coronavirus”. Therefore, strokes and haemorrhage are being present in people even after a month or two of recovery from mild COVID-19, which is surprising.
What Happens To The Brain?
Dr Sreekanth explains the following possible reasons as to why COVID-19 is affecting the brain:
- There are probably changes in the clotting factors, resulting in the clotting of blood vessels and veins
- There is also interference with the functioning of the immune system, leading to unwanted increased immunity in the body, resulting in disrupting one’s own body functions.
Studies and recent news reports have also shown that in some of the cases reported in China and Japan, the genetic material of the virus was found in the spinal fluid, whereas one reported in Florida found viral particles in brain cells. This has shown a possibility of the virus entering the bloodstream or nerve endings. The loss of smell that occurs in some patients with COVID-19 could indicate that the virus entered through the olfactory bulb, which is located right above the nose and communicates information about the smell to the brain. Another theory suggests that all of the physiological changes induced in the body by COVID-19 — ranging from high fevers to low oxygen levels to multiple organ failures — contribute to, or account for, brain dysfunction, such as the delirium or coma seen in many of the severe COVID-19 patients.
Therefore, COVID-19 has been seen to affect the nervous system of people infected with the novel coronavirus, but the exact reason still remains unknown. COVID-19 has been surprising us in the terms of its symptoms and effects since day 1 and thus, the best possible way is to prevent it, to avoid long-term damage to the brain and body.
