COVID-19’s bivalent boosters: 9 questions, answered

Last updated on Oct. 13, 2022

You may have heard that the Food and Drug Administration (FDA) has granted emergency use authorization to a new pair of COVID-19 booster shots. These updated vaccines are designed to help protect people from the most prevalent subvariants of the current strain: Omicron BA.4 and BA.5.

To learn more about these vaccines, including how they differ from previous COVID-19 booster shots, who is eligible to receive them, and when to schedule them in relation to your flu shot, we checked in with infectious diseases specialist and head of Internal Medicine David Tweardy, M.D.

What are these new COVID-19 boosters, and how do they differ from the existing ones?

Until now, COVID-19 booster shots have been monovalent or univalent. That means they only contained one version of the mRNA sequence for the SARS-CoV-2 virus’ spike protein — the one that came from the original strain which emerged in late 2019 in Wuhan, China.

The boosters that just got approved are considered bivalent vaccines. That means they contain the mRNA sequence for the spike protein of two strains of SARS-CoV-2:

1. the original strain from Wuhan, and
2. the current predominant subvariant of Omicron, BA.5.

The spike protein on the surface of both Omicron’s BA.4 and BA.5 subvariants is exactly the same. So, this booster should protect people against both.

Who is eligible for a bivalent COVID-19 booster shot?

The two vaccines have different age restrictions.

• Moderna: 6 years and older
• Pfizer: 5 years and older

You only need a single booster shot of the bivalent vaccine to be considered fully boosted, but you’re not eligible to get it unless you’ve already been fully vaccinated with either Johnson & Johnson/Janssen’s original one-shot regimen, or Pfizer or Moderna’s original two-shot regimen.

You’re eligible to get a bivalent booster shot two months after you’ve been fully vaccinated.

Can I get a bivalent booster now, if I just recently got my second univalent booster?

No. You’ll need to wait until two months have passed since your last booster shot.

But don’t kick yourself, even if you just got one and now wish you’d waited. The entire point of getting a booster shot is to continue expanding your protection. So, the more boosters you get, the better protection you’ll have.

That’s why I would get a bivalent booster shot as soon as I was eligible.

How long do I need to wait to get the bivalent booster if I’ve had COVID-19?

If you were very ill, you’ll need to wait at least until the worst of your symptoms have resolved, and you have met the criteria to leave isolation. Patients with recent COVID-19 infections also have the option of waiting three months instead of two (counting from the time they first showed symptoms or tested positive) to get a booster shot.

Talk with your doctor to determine the best timing for you to get one if you have any questions.

Are there any special considerations around scheduling, given that it's also time for flu vaccines?

No. The Centers for Disease Control and Prevention (CDC) say there’s still no need to stagger your vaccinations. So, if you’re due for both, you can get your flu shot and your COVID-19 booster at the same time on the same day. You can even get them in the same arm, if you want to cut down on the amount of soreness you experience.

Is there any reason not to mix and match boosters, by getting your bivalent from a different manufacturer than you did the first time?

No. It’s OK to mix and match as long as you’re eligible for the vaccine you prefer.

All of the data that previously showed there were no big differences between those who mixed and matched and those who didn’t still applies. I haven’t seen anything to even imply that anything’s changed.

What about immunocompromised patients? Any special rules for them?

No.

In fact, I am really excited about this latest development, because it could end up being a real game-changer for our immunocompromised patients.

It’s already becoming increasingly rare to die or become really ill from COVID-19. But this bivalent vaccine is another step in the march toward a more endemic stage.

The infrastructure is already in place to make massive quantities of vaccine in a very short time. So, anything after BA.5 could theoretically be added to the composition of the next booster. I think COVID-19 boosters will probably be multivalent from here on out, just like with the flu. And for patients who haven’t been able to mount a sufficient defense against COVID yet, maybe repeated boosters will finally allow them to get there.

Can I get the bivalent booster if I regularly receive EVUSHELD injections to protect myself from COVID-19?

Yes. Those who take EVUSHELD antibody therapy to protect themselves from severe COVID-19 infection can receive the bivalent booster, if eligible. Those who receive a vaccine dose (primary or booster) should wait at least two weeks before getting the EVUSHELD injection, according to the Centers for Disease Control and Prevention’s advisory group.

Where can I find a bivalent COVID-19 booster?

Once bivalent COVID-19 boosters become available, you should be able to obtain one anywhere you’d normally get a COVID-19 vaccination or flu shot.

Will I be able to get the bivalent booster at MD Anderson?

We expect to get bivalent boosters soon. When we do get them, they will only be available for MD Anderson patients and employees. Patients will be able to schedule a booster appointment via MyChart.

Request an appointment at MD Anderson online or by calling 1-877-632-6789.