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New COVID-19 boosters target variants

A woman in scrubs bandages another woman’s arm after a vaccine.

The virus that causes COVID-19 has evolved. So has our protection: Bivalent vaccines from Pfizer and Moderna can help give your immune system a boost against the Omicron variant. That's why the Centers for Disease Control and Prevention is encouraging everyone who is eligible to get the updated shots. Here's what to know.

Why do we need the new boosters?

The virus that causes COVID-19 changes with time. Some newer variants spread more easily. And they are better at evading the current vaccines. The bivalent boosters offer protection from the original strain of the virus. But they also target the spike protein that helps the Omicron BA.4 and BA.5 variants infect cells. This is not unlike how experts update the flu shot each year to match the circulating strains. Studies show that the new boosters work better against these newer strains.

Who can get them and when?

  • People ages 5 months and older who have completed their initial vaccine series can get the new booster if it has been at least two months since their last COVID-19 vaccine or booster dose.
  • Children who received the Moderna vaccine for their original series can get the bivalent booster if it has been at least two months since their last dose.
  • Children ages 6 months through 4 years who are currently completing their initial series of Pfizer vaccines will receive the updated shot as the third dose in the series.

Do I need this even if I'm already boosted?

Yes. You should consider getting the new booster if it has been at least two months since your last vaccine dose.

The new shots should provide better protection from newer Omicron variants. It's also important to remember that vaccine immunity fades with time. Booster shots help to restore this protection.

How many doses do people need?

Just one booster shot is enough to provide protection.

What are the potential side effects from a booster shot?

The most common side effects are like those seen with primary series COVID-19 vaccines. They include pain at the injection site, fatigue, headache and fever. These side effects, if they happen, usually last a day or two.

Who might not be able to get a booster?

People who may have safety concerns about COVID-19 boosters include those who:

  • Have had a serious reaction to a dose of COVID-19 vaccine or its ingredients.
  • Have ever had a severe reaction to any vaccine.
  • Have a moderate or severe acute illness.

You still may be able to get a booster shot in these situations. For instance, if you’re sick, you may have to wait a few days. Your doctor can advise you on the best course of action.

I’m not sure if a booster is right for me. How can I find out?

Talk to your doctor. They can help you understand the risks and benefits so you can decide what’s right for you.

Reviewed 12/15/2022
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