The COVID19 Vaccine: what is mRNA? Should I trust the vaccine?

Originally Posted to Facebook on December 5, 2020: https://www.facebook.com/savannahgsims/posts/10224758204047922

Okay, let’s talk about the COVID19 vaccine. This is going to be a long one, but here we go. In this post, I am going to briefly talk about how the vaccine for the coronavirus (SARS-CoV2) that causes COVID19 works and why I am cautiously optimistic for a safe and effective vaccine in coming months.

First of all: the 2 vaccines that it looks like most of us will receive, at least at first, are made by the companies Pfizer and Moderna. These companies both use a similar technology to produce a similar mRNA vaccine. What is an mRNA vaccine?

All of your cells have DNA. DNA is organized in your chromosomes. Every cell in your body has this DNA. DNA is important - but if all of your cells have this DNA, how does an eye cell know to be an eye cell and not a skin cell? How does your body know that it is time to break down alcohol after you drink a beer? This has to do with turning your DNA into proteins which are able to be used in your cells.

Think of DNA as the cookbook of your cell. It has all the recipes to tell your cell how to make the protein. In a process called transcription that turns DNA into messenger RNA (mRNA) this is making a photocopy of the single recipe that you want to make. The mRNA is the photocopy of the recipe you need so that the chef can look at the recipe. Next, mRNA is turned into protein in a process called translation. In this analogy, translation is akin to the chef taking the copy of the recipe (mRNA) and actually cooking it to become the dish (the protein).

mRNA vaccines utilize this process that always happens naturally in our cells to generate an immune response against SARS-CoV2 - the virus that causes COVID19. In these vaccines, mRNA will be delivered to your cells that encodes the “recipe” for the SARS-CoV2 spike protein (this is unique to the coronavirus). The spike protein is what the virus uses to enter our cells. Our cells will receive the spike mRNA, our cells will then turn it into the spike protein (the chef cooking). At this point, our cells will recognize this spike protein as foreign (the immune system is really good at distinguishing self and non-self). Now that our cells are making a foreign spike protein, immune cells will generate an immune response against the spike protein, and therefore, if exposed to the COVID19-causing virus, it will not be able to enter our cells. Viruses are useless without our cells because viruses cannot live without a host.

The good thing about this vaccine strategy is that we are NOT receiving the whole virus, so it is safe. Since we will only be exposed to one protein in the vaccine, there is not a risk of it replicating or spreading once you receive it. I also anticipate that this should be safer for people with less strong immune systems. There is also no possible way that these vaccines can change your own DNA. mRNA is an “intermediate” between DNA and protein. The mRNA is actually pretty unstable, so it will get naturally degraded in your cells pretty quickly and the only thing left behind will be your primed immune system ready to fight COVID if you are exposed to the virus!

I really recommend checking this out: https://www.nytimes.com/.../pfizer-biontech-covid-19...

It focuses on Pfizer, but Moderna will work similarly.

What about side effects? In science and medicine, side effects in clinical trials are referred to as “adverse events.” So far, the common adverse events that have come up in the SARS-CoV2 clinical trials include: muscle aches, headache, fatigue, redness at the injection site, chills, and fever. I know these side effects are unpleasant. If you get the flu shot, you are probably familiar with these icky side effects. However, this is NORMAL and a byproduct of your immune system being activated. I like to think of it as being really sore after a workout or doing a lot of yard work. It hurts and is not fun the next day, but you are proud of all the hard work you put in and know it is GOOD for your body in the long run.

I, personally, believe that the benefits of the COVID19 vaccine outweigh the side effects because it will likely provide protection against COVID19, a virus that is associated with long term organ damage and can cause death. We still are learning more about the long term effects of COVID19 infections, but there are reports that COVID19 infections can cause mood changes, long term fatigue, heart damage, brain damage, blood clots, potentially erectile dysfunction, and permanent lung damage. Personally, I would rather risk a day or two on the couch with hot tea and Netflix from the vaccine-associated side-effects than the long term issues associated with a COVID infection.

This brings me to the clinical trials themselves and how these vaccines are being evaluated for both safety and effectiveness. First, I will say that we (the public) have still not seen all of the data from the clinical trials. I am not personally too concerned about this, because it will come out, and this will end up being meticulously scrutinized by experts worldwide.

Pfizer has vaccinated about 43,000 people. Of those in the trial, there were 170 confirmed cases of COVID-19. 162 observed in the placebo group (did not receive the vaccine) versus 8 in the vaccine group. Moderna vaccinated around 30,000 people. There were 196 confirmed cases of COVID19 and 185 of those infections were in the placebo group and therefore did not receive the vaccine. Both of these trials were double-blind, meaning the participant and the person giving the vaccine did not know whether the injection contained the “real” vaccine or the placebo. This is a gold standard of clinical trials. Obviously, this is still not a huge number of COVID infections. The trial participants were still encouraged to practice social distancing, mask wearing, etc. to avoid infection. It is not ethical to knowingly expose people in the clinical trial to a potentially deadly virus.

This data has been released via a press release by the companies making the vaccine. However, a committee of experts with no financial interest in the companies did provide oversight and approval. Generally, scientists prefer data to be peer-reviewed, however, we are in a global emergency and the public is interested. These data will be submitted for peer-review, and I am excited for this to be published.

What now? We are waiting on the FDA to evaluate the safety and effectiveness of these data. If the FDA grants their approval, the distribution process will begin. I presume that it will be a slow roll out. There is still a lot to learn and hurdles to be jumped from a supply chain aspect, but I am hopeful for a brighter, safer, and healthier 2021.

Additional reading and sources:

DNA/RNA/Protein Biology Analogy:

https://ib.bioninja.com.au/.../translation-analogy.html

mRNA vaccines:

https://www.phgfoundation.org/briefing/rna-vaccines

https://www.cdc.gov/.../vacc.../different-vaccines/mrna.html

https://www.nytimes.com/.../pfizer-biontech-covid-19...

Company press releases:

https://investors.modernatx.com/.../moderna-announces...

https://www.pfizer.com/.../pfizer-and-biontech-conclude...

https://www.sciencemag.org/.../just-beautiful-another...

Regulatory and Safety:

https://www.statnews.com/.../dry-technical-but-important.../

https://www.fda.gov/.../coronavirus.../covid-19-vaccines....

https://www.healthaffairs.org/doi/10.1377/hlthaff.2020.01620