It is still unclear today how much the Coronavirus infection affects the entirety of the human body. What we know so far are its effects on the cardiovascular and respiratory systems, but there we have little knowledge about its nervous system effects.
Several Covid-19 patients showed mild to severe neurologic symptoms such as loss of sense of smell as far as stroke. The manifestations came in the form of delirium in 10 patients, 12 having meningitis, and eight patients with nerve damage and stroke. In the UK, more than 150 patients displayed psychotic and depressive tendencies in all ages.
The mechanism by which the virus exerts its destructive effect on that particular human body system is still unclear. But studies are well underway.
Loss of sensory abilities like smell and taste are the early warning signs. The symptoms then gradually progress to headache, dizziness, fainting, fatigue, mild seizures, and partial paralysis,
The path of the virus as it enters the human body is primarily through the nose. Viral cells could possibly penetrate the walls of the olfactory lining. Damage to the nasal nerves and taste buds could result in the symptoms mentioned. The sensory nerves will fail to transmit messages to the nervous system. Chances of recovery are quite high for the majority of the patients.
The angiotensin-converting enzyme, is also another factor that contributes to such effects, ACE regulates blood pressure by controlling levels of angiotensin 2, which causes vasoconstriction and lessen blood flow to various parts of the body.
In the event that the virus moves to attack the enzyme in the blood vessels, an autoimmune response is produced, known as a cytokine storm. During this time, the body releases a lot more fighting chemicals than usual. The reaction creates an inflammatory response which leads to the formation of blood clots in random locations, depending on the density of cytokines in the area.
Minor strokes are almost undetectable. As these strokes accumulate, cognitive problems occur. Other manifestations such as dementia, anxiety, depression, and insomnia may also be present. It could still also show even years after recovery as a person ages.
A form of destructive protein-antibody interaction that results in paralysis was also found in a few infected patients. It is referred to as the Guillain-Barre syndrome where nerves become damaged and cause delays in signal transmission or have no transmission at all. It is usually characterized by numbness in the lower limbs.
However, it is vital to note that every person has a different reaction to the virus because immune systems work differently depending on each person’s unique biochemistry.
In the case of asymptomatic patients, their immune responses were resistant enough to prevent cytokine formation.
Covid-19 is not the only virus to exhibit neurological complications. Other coronavirus strains, flu, measles, and Zika also have similar effects on the nervous system. Two factors are being looked at in the development: it could either be a direct effect of the virus infecting the human cells or a repercussion of the body’s exaggerated reactions to the foreign substance.
Not many related studies have been done so far with regards to neurological ailments that occur as a direct result of Covid-19 infection. Neurological symptoms for affected patients are being treated as independent disorders with the appropriate therapeutic approach.
Based on the few small-scale studies, the common denominator for severe infections is those with underlying diseases. These patients have higher affinity for acquiring more complications.
The virus and the disease that it brings is still an unfinished puzzle. In the face of adversity, medical experts and health professionals constantly keep exploring new possibilities in further uncovering today’s plague and it is certain that the more we know about it, the closer we are to winning the fight against it.