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What is in the COVID vaccines?

Health care workers answer questions about the COVID-19 vaccines.

Yvonne Maldonado, MD breaks down what’s in the COVID vaccines and how they work.

So, I’ll just explain briefly the two types of vaccines that we have available. So, one is the mRNA vaccine and the other is the viral vector vaccine. Now, this mRNA technology was used to develop a very small piece of mRNA that contains the code for the spike protein on the surface of the SARS-CoV-2 virus.

It’s a very small piece of messenger RNA and it is not live. It doesn’t come from human cells, from animal cells. It doesn’t use any live biological products. It is just pieces of nucleic acids that are in a little piece. And they are covered by a fat, a bubble, and they are so fragile that they need this fat bubble to keep them stable. So, they will fall apart if they’re not in this little fat bubble. And that’s what’s injected into the arm.

So, it’s using your own body’s machinery to make little pieces of what looks like the spike protein from the virus, but it’s not made from the virus at all. And then, the immune system recognizes those spike proteins and develops immunity to that. So, when you see the actual live virus your body recognizes it right away and destroys the virus.

So, it never has access to your DNA. And same thing with the Johnson and Johnson vaccine, it is made from an inactivated viral vector. So, all it makes is protein that looks like the spike protein from the virus. Nothing gets into your DNA. Those virus vectors have been certified by the FDA. They have been tested extensively and they do not get into your human DNA at all.

This information is shared for educational purposes only and should not be used as a substitute for professional medical advice. The views expressed are those of the featured medical professional and reflect information available to that professional at time of filming. Always consult a health care provider for any personal health decisions. Click here for vaccine FAQs from the CDC.

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Immunity wanes over time. Keep up your protection against COVID by getting boosted when eligible.

Updated (bivalent) boosters are now available for adults and children 6 months and older.