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How do the COVID vaccines work?

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

Edith Bracho-Sanchez, MD explains that COVID vaccines help train our immune systems to prevent serious illness.

Vaccines are supposed to train our body, train our immune system and get it ready so that if we are ever exposed to an illness, a virus, a bacteria as well, our body is ready. We’ve made those antibodies. We’ve activated other parts of our immune system to attack it and prevent it from making us really sick. So, that’s really it. It’s a heads up that we are giving our body. It’s a chance to sort of practice to make what’s going to protect us in the future. And I think it is also important to remember, it’s a safe way to train our immune system. Some people tell me, “Well, doctor, why can’t I wait to get the disease? And then my immune system is going to react anyway. Aren’t I going to mount the antibodies anyway?” I just always remind them, “Yes, but you run some risks when you get the illness itself. The vaccine is a safe way to give your body a heads up without running those risks and those complications that you could get if you get the real deal illness.”

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 boosters are available for adults and children 6 months and older.