Prevea Health

How do COVID-19 vaccines work?


What are mRNA vaccines?

mRNA, which stands for “messenger RNA”, vaccines teach your cells how to make a protein that triggers an immune response inside your body. The immune response, which produces antibodies, is what protects you from getting infected if the real virus were to enter your body.
mRNA vaccines are faster to produce than traditional vaccines because they can be developed using readily available materials.
Did you know? mRNA vaccines have been studied before for flu, Zika and rabies!
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I thought it took years to create vaccines. How can the COVID-19 vaccines be safe?

The Food and Drug Administration (FDA) gathered data from vaccine clinical trials to determine their safety and effectiveness. Next, the Advisory Committee on Immunization Practices reviewed the safety data and shared its recommendations to the CDC.
Because the CDC sets the United States’ adult and immunization schedules, it provided this information to state officials. This process creates checks and balances amongst government, medical and public health experts to ensure vaccine safety within the United States.
But, you are right; oftentimes vaccines do take years to develop. However, the COVID-19 vaccines had a few components that helped accelerate their timelines:
  1. Researchers used existing clinical trial networks to begin conducting clinical trials which meant they could leverage existing infrastructure and secure thousands of volunteers to participate.
  2. Manufacturing started while the clinical trials were still underway. Normally, manufacturing doesn’t begin until after completion of the trials.
  3. The Food and Drug Administration and the Centers for Disease Control and Prevention (CDC) prioritized the review, authorization and recommendation of the vaccines.
Rest assured, safety has not been sacrificed for speed. They are being held to the same safety standards as all other vaccines. The FDA and CDC will continue to monitor the safety as more patients are vaccinated.
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If COVID-19 vaccines are two doses, do I need to get both?

Yes, you will need both doses for full protection against COVID-19. The first shot you receive primes your immune system, which helps it recognize the virus. The second shot you receive strengthens your immune system.
Tip: After you receive your first dose, schedule your appointment for your second before leaving the clinic.

What are side effects of COVID-19 vaccines?

Patients can anticipate minor side effects after vaccination, especially after the second dose. However, there were no significant safety concerns identified in the clinical trials.
Side effects may include:
  • Fever
  • Headache
  • Muscle aches
  • Sore, tender arm
Side effects like these should resolve on their own within a week and are a sign that your immune system is doing exactly what it is supposed to do. It is working and building up protection to disease.
Tip: Ask to receive the vaccination in your non-dominant arm. Because you use this arm less, you may not notice soreness as much as if you were vaccinated in your dominant arm.
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If it will take months before I can get vaccinated, what should I do to stay safe in the meantime?

Remember, a COVID-19 vaccine is one layer of protection. Continue wearing a mask around others, avoiding close contact with people who are sick, maintaining 6 feet of distance from others and washing your hands often.