Abstract
SARS-CoV may become an endemic virus, but public health care is expected to gain more control over it. The family of the virus is Coronaviridae, and it is of the genus Betacoronavirus. It consists of the viral proteins spike glycoprotein (S), viral membrane glycoprotein (M) and envelope (E), which are embedded in host membrane-derived lipid bilayer. The virus has a lytic lifestyle and can affect both humans and animals. Antiviral and antibiotic agents, corticosteroids, and anti-malarial agents are considered to be the most effective drug classes to treat COVID-19, caused by SARS-CoV-2.
Article Summary
According to the article by Phillips, almost 90% of experts currently believe that SARS-CoV-2 will become an endemic virus (Phillips, 2021). However, the effects of the virus will not be as large-scale as before, due to annual vaccination and acquired immunity. Just like with OC43, 229E, NL63 and HKU1 viruses, SARS-CoV-2 virus might become a disease first encountered in the childhood, which could allow for developing immunity to it. Nevertheless, there are already cases that show that the virus can evolve to escape it; therefore, it is highly possible that immunity will wane after a couple of years. This is one of the major contributing factors of the virus becoming endemic. Vaccination of people vulnerable to severe diseases will allow to reduce infections.
Pathogen Information
Classification of microorganism
SARS-CoV-2 of the genus Betacoronavirus is a virus that causes COVID-19 and belongs to the family Coronaviridae.
Cellular/ structural (in case of viruses) characteristics
SARS-CoV-2 has surface viral proteins: spike glycoprotein (S), viral membrane glycoprotein (M) and envelope (E) of SARS-CoV-2 are embedded in host membrane-derived lipid bilayer encapsulating the helical nucleocapsid, which comprises viral RNA. It is from 26 to 32 kb in size, having 6–11 open reading frames that lack hemagglutinin-esterase gene. SARS-CoV-2 has a unique FCS and is able to manipulate host immune response. It can also mimic an epithelial ion channel to hijack host cell machinery; its proteins facilitate host cell invasion (Kumar et al., 2020). To understand the pathomechanisms of the virus, it is important to target these virulence factors.
Susceptibility to antibiotics/ antiviral or antifungals
A range of drugs has been used to combat SARS-CoV-2. Among them are Remdesivir, Favipiravir, Hydroxychloroquine, Azithromycin, Lopinavir/Ritonavir, and Nafamostat mesylate. Because the RNA replication and protein synthesis are important for viral replication, many potential treatments target these processes. The drugs mentioned have proved to exert an antiviral activity more effectively than others, with Remdesivir and Favipiravir being more promising despite the fact that they are believed to have side effects.
Growth conditions
The virus shows a lytic lifecycle, going through three stages: the attachment and entry, replication and synthesis, viral assembly and release. Individuals can be infected with SARS-CoV-2 after inhaling airborne viral particles, which encounter respiratory epithelium cells in the trachea and lungs. The natural host for the virus is currently the bat, but SARS-CoV-2 can affect other animals as well, such as cats, snakes, ferrets and minks.
Evasion of immune system
Upon entering the body, the virus looks for cells with right receptors. Specific spike protein bind to a specific receptor called ACE2. The virus is then able to enter and release its RNA into the cell. It can now hijack the cell’s ribosome and turn its own viral RNA into protein that creates the components necessary for a new virus. It breaks out of the cell, destroying it, with all the new viruses moving on to other cells to repeat the process.
Disease(s) caused, symptoms, diagnosis, and therapeutic interventions
SARS-CoV-2 causes COVID-19. The most common symptoms include fever, dry cough, loss of taste or smell, chest pains, headaches, and sore throat. Viral nucleic acid detection by RT–PCR is generally applied in diagnostic tests. Currently, the most common drug types to treat COVID-19 are antiviral and antibiotic agents, corticosteroids, and anti-malarial agents. However, the efficacy if these drug classes cannot be fully supported due to the lack of sufficient evidence.
References
A perspective on emerging therapeutic interventions for COVID-19. (n.d.). PubMed Central (PMC).
Coronavirus disease (COVID-19): A scoping review. PubMed Central (PMC).
Kumar, A., Prasoon, P., Kumari, C., Pareek, V., Faiq, M. A., Narayan, R. K., Kulandhasamy, M., & Kant, K. (2020). SARS-Cov-2 specific virulence factors in COVID-19. SSRN Electronic Journal.
Phillips, N. (2021). The coronavirus is here to stay — here’s what that means. Nature, 590(7846), 382-384.