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COVID-19 boosters target variants

A man holds up his sleeve to show his vaccine bandage

The virus that causes COVID-19 has evolved. So has our protection: The new COVID-19 vaccines and boosters are designed to protect you from the latest variants—such as Omicron variant XBB.1.5. Here's what to know.

Why do we need the updated boosters?

The virus that causes COVID-19 changes with time. Some newer variants spread more easily. And they are better at evading the original vaccines. According to the U.S. Food and Drug Administration (FDA), the new shots were updated to target the variants that are spreading now. That's similar to the way flu vaccines are updated each year to fight the current strains.

Who can get them and when?

Almost everyone who is 6 months or older can get the new shot—as a booster or as their primary vaccine.

  • People 5 and older can get the new shot if it's been at least two months since their dose of any COVID-19 vaccine. Most people need only one dose of the new vaccine. That's true whether or not they were vaccinated before.
  • Children ages 6 months to 4 years can get the updated vaccine too. The number—and timing—of doses depends on your child's vaccination history and which brand of shot you choose. Kids under 4 years old who are already vaccinated will need one or two shots as a booster. If it's your little one's first set of COVID-19 vaccines, they'll need either two or three doses. Ask your child's pediatrician for guidance. 

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

Nearly everyone 6 months and older should get the updated vaccine, according to the Centers for Disease Control and Prevention.

That's because:

  • Vaccine protection fades over time.
  • New variants continue to evolve and spread. The new shots are designed to protect you from the current strains of the disease. They can help keep you and your loved ones from getting very sick.

What are the potential side effects from a booster shot?

The most common side effects are like those seen with past 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. 

If you or your child has had an allergic reaction to a COVID-19 vaccine or its ingredients—or to any vaccine—talk to your doctor. They 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?

Share your concerns with your healthcare provider. They can help you understand the risks and benefits so you can decide what’s right for you.

Reviewed 9/12/2023


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