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COVID-19 Vaccines: What you should know!- Part 1

So the biggest infection happening right now is SARS-COV-2 or COVID-19. Unfortunately, it has infected >102 million people leading to >2 million deaths worldwide according to the World Health Organization. In the United States (US), there are >25 million people with COVID-19 which has resulted in >400,000 deaths since the start of this pandemic. The US has the highest number of COVID-19 cases globally despite only making up ~4% of the World’s population. India has the 2nd highest number of COVID-19 cases but it also has the 2nd highest population in the world behind China. There are many reasons why the US has had difficulty controlling this pandemic but we are not going to go there. We are actually in luck because we now have multiple COVID-19 vaccines available for stop the spread of this terrible disease. How do I know vaccination can do this? Because vaccination has lead to the elimination of Smallpox and the control of many other infections that was infecting and killing many Americans. Below are answers to come common questions:

What is the difference between SARS-COV-2 and COVID-19?

SARS-COV-2 stands for severe acute respiratory syndrome coronavirus 2 which is the name of the virus that is causing COVID-19.

COVID-19 stands for coronavirus disease 2019- Remember this virus was first described in Wuhan, China in December 2019.

This means, SARS-COV-2 is the virus and COVID-19 is the disease.

How do the Pfizer and Moderna mRNA vaccines work?

Spike protein is unique to SARS-COV-2. This is why scientist decided to make a vaccine that targets this protein because they wanted it to be specific for SARS-COV-2 and not other infections.

  1. Messenger RNA (mRNA) is genetic material that provides the "road map" for the production of the spike protein once the vaccine is inside the cell.

  2. mRNA is not stable and is quickly broken down enzymes called RNase. Therefore, it has been mutated to stabilize the structure and it is the surrounded by the lipid membrane (nanoparticle-formulated) so keep it stable enough be injected in the body.

  3. The mRNA in incorporated in certain cells immune cells called antigen presenting cells (APC). Proteins within the cells read the mRNA and eventually produce Spike proteins which are the same Spike proteins that are found on the SARS-COV-2 virus.

  4. These proteins stimulate the immune system to produce antibodies and other immune cells to fight off infection from the SARS-COV-2

Lastly, I wanted to highlight the fact that once the mRNA stimulates Spike protein production in cells, it is degraded and no longer functions in the body. Additionally, it does not incorporate itself into the body's DNA.

Do I need both shots of the Pfizer and Moderna vaccines?

Yes! These vaccines require 2 doses in order to provide the >90% efficacy

If I've already had COVID-19 do I need the vaccine?

Yes! We don't know how long natural infection will protect you. Some people are getting reinfected after having COVID-19. Vaccination produces a more reliable immune response and is more protective against future SARS-COV-2 exposure than getting the disease. Besides, this is a disease that people are dying from. It is safer to get vaccinated than to actually get COVID-19

How was the vaccine created so quickly?

The mRNA vaccines are relatively new but not brand new. The actual basic science behind mRNA vaccines have been around for a least the last few years. There have been mRNA vaccine candidates for Ebola and Influenza prior to the SARS-COV-2 vaccines. Check out the article for more info:

So, now that we know the technology was there, how did they fast track the clinical trials? Normally, the clinical trials are done in sequential order, Phase 1 THEN Phase 2 THEN Phase 3 THEN Phase 4. However, they completed multiple phases at once in order to expedite the process.

Lastly, here in the US, the Food and Drug Administration (FDA), has approved the Pfizer and Moderna COVID-19 vaccines for emergency use authorization (EUA) which gets in on the market faster because its an emergency.

Check out my YouTube video to review the science behind the Pfizer and Moderna vaccines.




Thanks for stopping by! 

Dr. Byrd

is currently a Pediatric Infectious Disease fellow at Lifespan/Brown University and is board-certified in adult infectious diseases. She is passionate about infectious diseases and loves to share her knowledge with others. 

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