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The Covid-19 Pandemic has seemed unyielding during its year-long reign, causing innumerable damages economically, socially, and politically on a global scale. One of the most taxing aspects of the pandemic is its uncertain nature. Nobody knows when the pandemic will end, let alone when a sense of normalcy will be achieved again. There does appear to be a new hope, however, for the beginning of such a journey. Covid-19 vaccines have been developed using novel mRNA technology that harnesses the body’s ability to produce proteins to induce an immune response. Though the technology had not been used in humans before, preliminary data from the Moderna vaccine trial indicates the technology has the potential to induce herd immunity more quickly and effectively than contemporary vaccine methods. The technology also provides unique opportunities for treating a myriad of diseases, even those that are not virulent in nature such as cancer.

To understand how the mRNA vaccines function, it is important to know how Covid-19 affects the body and immune system. When Covid-19 particles are inhaled they make their way down the trachea, through the bronchial tubes, and into the lungs. The cells that make up the lungs have specific sets of receptors that molecules such as hormones latch onto in order to enter the cell. The Covid-19 virus contains a spike protein that is able to latch onto a receptor called the ACE2 receptor which allows the virus to merge with the cell. Once inside the cell the RNA that was contained in the Covid-19 virus acts as a set of instructions for proteins to be created that allow for more viral particles to be created (Scripps 2021). These particles are released when the virus forces the cell to lyse (burst) and, upon the cell lysing, are free to infect new cells. When this process overwhelms the immune system in Covid-19, the immune system goes into overdrive and starts attacking healthy cells as well in an attempt to contain the virus. Thus, it is important to grant immunity to as many people as possible so that their bodies can safely and effectively deal with the virus.

Immunity is granted when enough antibodies are present that the pathogen is marked and destroyed faster than it can replicate, and this idea is why mRNA that encodes antibodies makes for an extremely potent vaccine. The novel mRNA vaccines bypass the need for the body to be exposed to the pathogen (which includes a risk of complications related to the pathogen), and instead deliver the instructions for the antibodies directly to immune cells such as the B-Cell through lipid (fat) nanoparticles that are absorbed into the cell (Pardi, Hogan, et al. 2018: 3–4). The mRNA does not interact with DNA, as is a common misconception, but instead acts like instructions for the step-by-step production of a protein. The cell then undergoes a process called translation where an organelle in the cell called the ribosome assembles the protein amino acid by amino acid, almost like a set of LEGOs. For Covid-19, the mRNA instructs the cell to create an antibody specific to the spike protein, allowing for a rapid immune response if the patient was exposed to the virus. This allows for a more immediate induction of immunity, as well as one that lasts longer and can attack viruses that cause repeat infections (Pardi, Hogan, et al. 2018: 7).

Knowing how the mRNA vaccine worked in theory was one thing, but its implementation had never before been tried and thus must be studied. Though still ongoing, the preliminary report on the Moderna vaccine candidate offers a first glimpse at how safe and effective the technology can be. Dosages of 25, 100, and 125µg of the vaccine were tested in an open label, non-blind study conducted with forty-five participants aged eighteen to fifty-five. The participants were evenly split between these three groups, with four participants of each group being sentinel patients that got the vaccine sooner to ensure its safety. The participants recorded their symptoms in a memory aid, and the data analyzed on vaccine efficacy stemmed from tests done on extracted blood. Through analysis of this data, it was determined that the symptoms were not severe enough to represent a risk to the general population, and that the vaccine caused the immune system to destroy greater than eighty percent of the virus in tested blood (Jackson et al. 2020). The trial did not include a large sample size, which makes extrapolating the data to the population as a whole harder due to higher requirements for statistical significance. The study was justifiable in its small sample size in order to control liability if complications arose. Furthermore, the lack of pregnant patients or patients of color makes the data hard to extend to these groups as well. Though stringent and repeatable, a more ethical version of the trial would include these populations, as they are at some of the highest risk for Covid-19 complications. With that being said, this study is still highly important because its success allowed for the Moderna vaccine to get emergency approval to combat the Covid-19 pandemic. For many, this is a light in the darkness which represents the beginning of the end of the pandemic.

The significance of the Moderna trial cannot be overstated. The safety and efficacy of the vaccine lends credence to the thought that mRNA technology is not only safe, but potentially revolutionary. The technology could be used to revolutionize how the flu vaccine is distributed (Pardi, Parkhouse, et al. 2018), or even treat cancer (Pardi, Hogan, et al. 2018: 9–10). Though such breakthroughs are still far off, the proof of concept provided by the Moderna vaccines is a promising start. Furthermore, the ability to develop vaccines in a quick and efficient manner that mRNA offers will be an invaluable tool in fighting future pandemics as global population density continues to rise. For now, though, the Moderna vaccine trial has paved the way for vaccine distribution globally that signals the beginning of the end for a pandemic that seemed endless.


How does the novel coronavirus infect a cell? | Scripps Research. [accessed 2021 Feb 17]. simplified/how-the-novel coronavirus-infects-a-cell/index.html.

Jackson LA, Anderson EJ, Rouphael NG, Roberts PC, Makhene M, Coler RN, McCullough MP, Chappell JD, Denison MR, Stevens LJ, et al. 2020. An mRNA Vaccine against SARS-CoV-2 — Preliminary Report. N Engl J Med. 383(20):1920–1931. doi:10.1056/NEJMoa2022483.

Pardi N, Hogan MJ, Porter FW, Weissman D. 2018. mRNA vaccines — a new era in vaccinology. Nat Rev Drug Discov. 17(4):261–279. doi:10.1038/nrd.2017.243.

Pardi N, Parkhouse K, Kirkpatrick E, McMahon M, Zost SJ, Mui BL, Tam YK, Karikó K, Barbosa CJ, Madden TD, et al. 2018. Nucleoside-modified mRNA immunization elicits influenza virus hemagglutinin stalk-specific antibodies. Nat Commun. 9(1):3361. doi:10.1038/s41467-018-05482-0.


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“SARS-CoV-2 (µ-IMAGE) vaccines: mRNA-1273 (moderna), Ad5 (CanSinoBio, NantKwest/ImmunityBio), ChAdOx1 nCoV-19 (Oxford university). – Other remedies: S309 (antibody), hydroxychloroquin (Malaria-medicament), fluvoxamin (Antidepressivum), famotidine(heartburn)” by quapan is licensed under CC BY 2.0

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