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9 things to know about the new bivalent boosters for COVID-19

| Healthy You | COVID-19

Woman holds up two fingers in a v as she receives vaccination and takes selfie

Booster shots containing the original COVID-19 vaccine and an updated version targeting the omicron variant are now available

You may have heard of the new COVID-19 bivalent booster and wondered what it is. In simplest terms, it's an updated booster shot that the Food and Drug Administration (FDA) granted Emergency Use Authorization on Aug. 31. The updated booster was developed to help protect against omicron subvariants BA.4/5, which are currently the dominant strains of COVID-19 in the United States.

The original COVID-19 vaccines and boosters did an excellent job preventing severe illness and hospitalization, even during the delta surge in fall 2021. Then came omicron in early 2022. Despite being vaccinated and boosted with the original COVID-19 vaccine or having previously recovered from COVID-19, omicron's easy transmissibility resulted in many people becoming infected with omicron or its subvariants BA.4/5. Seeing the strength of the omicron subvariants, scientists updated the vaccine to be more effective against them.

How do the updated (bivalent) boosters differ from the original (monovalent) vaccines?

When developed in late 2020, the original vaccines contained only one strain of the original coronavirus—a monovalent or single-strain vaccine. Since then, the virus has mutated multiple times, with each mutation evolving the speed and severity at which the virus is spread.

The bivalent booster is the most recent version of the COVID-19 vaccine. The term "bivalent" means that the boosters target two strains of COVID-19. It contains the original vaccine strain and a strain derived from the BA.5 omicron variant. Since it contains two strains, it is more effective at protecting against the newer variants currently spreading in the U.S. and worldwide.

As the COVID-19 virus continues to change, vaccines must keep pace. Vaccines containing multiple virus strains have been used for decades. Every year the flu vaccine is reformulated to protect against the most common strains of influenza in circulation. It typically contains three or four strains to provide the best coverage and be the most effective.

We should expect scientists to regularly produce an updated COVID-19 vaccine so that, like the flu shot, people have the best protection against the COVID-19 variants that are spreading or predicted to spread.

How effective are the updated boosters? 

Medical experts believe that the updated boosters will work better in preventing omicron BA.4/5 infections while keeping strong protection against severe disease from all COVID-19 strains. In clinical studies, researchers found that people who received an updated booster had a better immune response against the omicron subvariants than those who received the original booster.

Like the original vaccine, the updated boosters will not prevent someone from getting COVID-19, but they will protect you against severe disease leading to hospitalization and even death.

Who is eligible for an updated COVID-19 booster shot?

The Centers for Disease Control and Prevention (CDC) recommends that everyone 5 and older receive one updated booster if it has been at least two months since their last COVID-19 vaccine dose, whether it was their final primary series dose or an original (monovalent) booster. People who received more than one original booster are also recommended to get an updated booster.

For children, 5-year-olds can only get a Pfizer booster, whereas those ages 6–17 can get a Pfizer or Moderna booster.

Boosters are not approved for children 6 months to 4 years old, although they may be approved in the future.

Are the updated boosters safe, and what are the side effects?

The updated boosters work the same way as the original COVID-19 vaccines and boosters and are made the same way. Because of that, there is no reason to think they will be any less safe.

The side effects of the updated booster are like those reported with the original vaccine. People commonly experience tenderness, redness or swelling at the injection site, fatigue, headache or muscle aches.

Can I get an updated booster if I recently got an original one?

You must wait a minimum of two months before getting the updated booster. The updated booster is being administered to people 5 and older who received either the second dose of their primary series or their last booster shot at least two months prior.

How long do I need to wait to get an updated booster if I've had COVID-19?

If you recently had COVID-19, you may consider delaying your booster by three months from when your symptoms started or, if you had no symptoms, when you first received a positive test. Talk with your primary care physician if you have questions about timing.

Can I get my updated booster and flu vaccine at the same time? 

Yes. The CDC says there is no need to stagger your vaccinations. If you are due for a booster and the flu shot, you can get them at the same time. People who have gotten both together do not report any different or more adverse side effects.

Can you mix and match boosters by getting one from a different manufacturer than you did the first time? 

Yes. You can get a different brand vaccine for your updated booster than you received for your primary series or earlier booster shots.

Where can I find an updated COVID-19 booster? 

PeaceHealth only offers the Pfizer updated booster to people 5 years and older. Appointments are required. To schedule, please call your primary care provider or request an appointment through our patient portal, My PeaceHealth.

If you prefer to receive the Moderna updated booster, it is available through many community clinics and pharmacies. You can find locations by ZIP code at, by calling 1-800-232-0233 or by texting your ZIP code to 438829.

There are currently no out-of-pocket costs for the vaccine or booster shots, though your insurer may pay the cost of administering the vaccine.

Please speak with your primary care physician if you have questions about the updated boosters. Additional information about COVID-19 vaccines is available on our COVID-19 website.

Source: Centers for Disease Control and Prevention