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COVID-19 Vaccine

Protecting our community with immunity through vaccination.

When can I get the vaccine?

The vaccine is strongly encouraged for all adults, and it is available to anyone over the age of 12 in the state of Missouri.

How does the vaccine work?

The first two approved vaccines to earn authorization - those developed by Pfizer and its German partner, BioNTech, and Moderna - use messenger RNA (mRNA) to instruct the body to build the Coronavirus’ signature spike protein. The body then produces antibodies to combat the Coronavirus when it enters the body.

The Pfizer-BioNTech vaccine requires two doses given 21 days apart, while the Moderna vaccine requires two doses given 28 days apart. Data from the clinical trials found the Pfizer-BioNTech vaccine to be 95% effective after two doses and the Moderna vaccine 94.1% effective, meaning they prevented people enrolled in the trial from getting COVID-19.

Facts about COVID-19 mRNA vaccines:

  • They cannot give you COVID-19.
    • mRNA vaccines do not use the live virus that causes COVID-19.
  • They do not affect or interact with your DNA in any way.
    • mRNA never enters the nucleus of the cell, which is where our DNA (genetic material) is kept.
    • The cell breaks down and gets rid of the mRNA soon after it is finished using the instructions.

Learn more about mRNA vaccines.

In an ensemble trial, Johnson & Johnson’s single-dose COVID-19 vaccine was 85% effective against severe/critical disease and demonstrated protection against hospitalization and death.

Is the vaccine safe?

The vaccines have passed the same rigorous Food and Drug Administration (FDA) standards as other vaccines. They were tested in a large clinical trial — made up of adults of different ages, races, ethnicities and medical conditions — to ensure they met safety standards. Because of modern technology, years of previous research on similar viruses and an enormous amount of funding, these vaccines were able to be developed at an unprecedented speed - while still meeting rigorous safety standards.

  • The FDA carefully reviews all safety data from clinical trials and authorizes emergency vaccine use only when the expected benefits outweigh potential risks.
  • The Advisory Committee on Immunization Practices (ACIP) reviews all safety data before recommending any COVID-19 vaccine for use.
  • FDA and Centers for Disease Control and Prevention will continue to monitor the safety of COVID-19 vaccines to ensure even very rare side effects are identified.

You cannot get COVID-19 from the vaccines. Some participants in the trials did report side effects similar to mild symptoms of Coronavirus infection, including muscle pain, chills and a headache. Serious reactions were rare.

What if I have already had COVID-19?

If you have already had COVID-19, there is evidence that you can still benefit from the vaccine. At this time, experts do not know how long someone is protected from getting sick again after recovering from COVID-19. The immunity someone gains from having an infection, called natural immunity, varies from person to person. Some early evidence suggests natural immunity may not last very long.

More Frequently Asked Questions

Q: If I get the vaccine, do I still have to wear a mask?

A: Yes. Masking, handwashing and physical distancing remain necessary until sufficient immunity is present in the population. The best protection we can offer each other right now is to continue to follow current guidelines when at work and in our personal lives, when appropriate. Evidence will be continuously reviewed, and practices continuously modified in regard to public health interventions.

Q: How long will I have immunity after getting a vaccine, and will it last longer than immunity from having the disease?

A: Because this virus is new, we don’t know how long immunity lasts — either for infection or vaccination.

Q: Should I wait after getting my flu shot to receive a COVID-19 vaccine?

A: There is no need to delay getting a COVID-19 vaccine because you recently had a flu shot. Patients in the COVID-19 vaccine trials also received flu shots as they became available.

Q: What are common reactions to the vaccine?

A: Most reactions are mild to moderate and are similar to side effects seen with other immunizations. These can include fever, soreness at the injection site, or even a temporary flu- like feeling with muscle aches, headache or fatigue.

Q: What if I have a reaction to the vaccine?

A: Some people might develop temporary flu-like symptoms, including fever, shortly after the second dose. This reaction is not an infection or sickness but is part of the immune system’s reaction to “seeing” the proteins from the vaccine.