A brief look into the anatomy of the Covid-19 virus and the most common respiratory and neurological consequences we have seen in the human body.
The Covid-19 virus, also known as SARS-CoV-2, consists of a positive single-stranded RNA that is enveloped by a capsid with four structural proteins: S protein, M protein, E protein, and N protein. The S protein is the most important when it comes to advancements in medical treatments against Covid-19 because of its high affinity for ACE2 target cells and ability for cellular entry, making it a critical focus in past and current vaccine research and progression. This spike protein contains a specific receptor binding domain that seeks out the ACE2 receptor in the lungs, heart, kidneys and intestines, and attaches and fuses the virus with the host cell. The M and E proteins play a critical role in turning the reproductive mechanism in the host's cell into a viral particle production machine allowing rapid reproduction of new viruses. The S, M, and E proteins are found on the surface of the virus while the N protein is found inside the cell, attached to the single strand of viral RNA, deflecting and inhibiting the defense mechanisms of the host cell while aiding in the replication of new RNA. The viral envelope which covers the capsid and lays under the surface proteins protects the virus from the outside world but disintegrates when it comes in contact with soap leading to viral death, which is why washing your hands regularly with hot soap and water slows the spread of the virus. A combined effort from the proteins leads to a deadly and highly contagious virus.
The most common manifestations of SARS-CoV-2 in the human body have been contained to the respiratory tract and a range of neurological side effects that are most often caused by the virus attacking the central nervous system. Cases of viral pneumonia were the most severe in the beginning of the pandemic, causing patients to be hospitalized and treated with oxygen, ventilators, IV fluids, and antiviral medications. These treatments were supportive and did not cure the illness, and effectiveness relied on the severity of the infection. The neurological consequences were seen more abundantly in patients with severe respiratory infection, and ranged from encephalitis to anosmia and ageusia and was often presented with muscle weakness and severe fatigue. A majority of these symptoms were obvious within the first two days of infection, with the most severe neurological consequences being displayed after this early infection period. As more mutations of the virus appeared, the severity of cases varied with most infected people presenting with loss of smell and taste and acute respiratory infections.
Author : Savannah Simonds
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