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How do we know the COVID vaccines are safe?

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

Shaquita Bell, MD explains that the COVID vaccines went through rigorous testing to ensure safety.

When people ask me about the safety about vaccines, I try to, first of all, just explain the science. So, the Pfizer and Moderna vaccines are based on mRNA technology and there’s been a lot of talk and a lot of press around, you know, is this new? And is it studied? How can we possibly know if it’s safe if we just developed it 18 months ago? And the reality is mRNA technology has been around for decades, almost 20 years. And, we know that it’s safe and we know that we’ve used it in many other uses, but we haven’t done it specifically for coronavirus. So, it is new to coronavirus, but is not new technology. And the mRNA technology is cool because you do not have to put any virus into somebody’s body. You’re really just putting what I call a flag, you’re injecting something into the system that your body recognizes and says, “Hey, what’s this message somebody is trying to send me?” And your body, reads it and says, “Oh, there’s an infection called coronavirus. I should learn how to fight that coronavirus.” And that mRNA really just gives it the instructions on how to fight it and how our bodies fight infections is through antibodies. So, we develop antibodies, which then fight the infection and prevent us from getting sick and acquiring coronavirus. And what we found is that this vaccine through giving it to thousands and thousands and hundreds of thousands of people is not only is it very safe, the side effect, the side effects of which are very, very low but it also is very effective.

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.

Stay up to date with your COVID vaccine, including boosters!

COVID vaccines are safe and effective for everyone ages 6 months and older.

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.