Omicron Boosters: 9 Questions Answered About the Updated COVID-19 Shots

3. Will they hold up against new subvariants that are circulating?

When the bivalent boosters were being made, omicron’s BA.4 and BA.5 were the greatest threats. BA.5 continues to circulate in the U.S. — it's responsible for about 11.5 percent of new COVID-19 cases, according to the CDC. But BA.4 is losing its steam, and other subvariants, like BQ.1, BQ.1.1 (both descendants of BA.5) and BF.7, are quickly gaining ground.

A big question on the minds of many: Will these new boosters still be able to stand up to other omicron subvariants? The short answer is yes, they should be able to, says the FDA’s Bumpus.

“The subvariants all have differences, but some similarities. And so by using these updated boosters that are developed to target omicron, specifically, we expect that there will still be a high level of protection against emerging subvariants.”

White House COVID-19 Response Coordinator Ashish Jha, M.D, had a similar response: “Based on everything we know right now, we believe that the brand-new updated COVID vaccines should provide a high degree of protection against BQ.1.1 and other subvariants that emerge,” he told AARP.

4. Who is eligible for the new boosters?

It doesn’t matter how many boosters you have under your belt right now — none, one or two. As long as you’ve had your primary series, you can get an updated booster if you are 5 years and older and it’s been at least two months since your last shot. Children as young as 6 months old who were vaccinated with Moderna are also eligible for a bivalent booster.

This doesn’t necessarily mean you’ll need to get boosted every two months from here on out, though. “What the interval will be is currently not known,” Schaffner says, adding that a lot will depend on how often the virus mutates and to what extent.

The goal, health officials have said, is to offer the booster on an annual basis, like the flu shot. That said, if the virus “starts genetically flip-flopping and doing more, well, we might have to [get boosted] a little more frequently,” Schaffner says. “But it remains to be seen.”

So far more than 42 million Americans have received the new bivalent shot; about 34 percent of Americans 65 and older have rolled up their sleeves, according to CDC data.

Kenneth Koncilja, M.D., a geriatrician at Cleveland Clinic, is recommending that all his patients get the new booster. The reason? He saw more cases of COVID-19 in his hospital this summer than in past years. “And I’m worried about the fall and winter,” he said, pointing to the time of year when respiratory illnesses pick up.

Influenza activity is surging in most regions of the country, the latest CDC surveillance data shows. Cases of respiratory syncytial virus (RSV), which sends more than 177,000 older adults to the hospital each year, are also spiking.

“It’s really important to think about the fact that these updated vaccines, because they have a specific targeting, will help to update our immune system and give us the increase in protection that we need, especially as we look toward winter when more people are indoors,” Bumpus says. “So I urge everyone to get the updated boosters and to really understand the fact that remaining up to date on our vaccines is a key part of keeping us as healthy as we can be.”

5. If I just had COVID, should I wait on the booster?

If you just had COVID-19 — and millions did this summer and fall — talk to your doctor about the best time to get your next booster. Reinfection is less likely in the weeks to months after infection, the CDC says, so if you don’t have any underlying risks and infection rates aren’t particularly high in your area, it may be appropriate to hold off a little longer (about three months) for your booster.

6. What about safety and effectiveness?

A large CDC study published Nov. 22 found the new boosters provided "significant additional protection” against symptomatic COVID-19 in people who were at least fully vaccinated with the original (monovalent) vaccine. Vaccine makers Pfizer and Moderna have reached similar conclusions in clinical trials examining the effectiveness of the updated boosters, and no red flags have been raised when it comes to safety.

Pointing to the latest booster data, top infectious disease expert Anthony Fauci said in a Nov. 22 press conference, “We know it's safe. We know that it is effective. So, my message … is: Please, for your own safety, for that of your family, get your updated COVID-19 shot as soon as you're eligible to protect yourself, your family and your community.”

7. What are the side effects of the booster shots?

If you’re curious about what to expect when it comes to side effects from bivalent boosters, nothing is really different. The most commonly reported side effects among study participants who received a bivalent omicron (BA.1) booster shot from Moderna were in line with the side effects some people experienced after the initial vaccine and booster: pain, redness and swelling at the injection site; fatigue; headache; muscle pain; joint pain; chills; nausea/vomiting and fever. What’s more, Moderna reported that side effects from the BA.4/BA.5 bivalent booster were generally lower than previous vaccine doses. 

Pfizer’s bivalent BA.1 study yielded similar results, with the most commonly reported side effects being pain; redness and swelling at the injection site; fatigue; headache; muscle pain; chills; joint pain; diarrhea and fever. When it comes to the BA.4/BA.5 bivalent formula, Pfizer says the safety profile is similar to the previous version of the vaccine.

Experts have said they will continue to keep an eye on the rare risk of myocarditis, an inflammation of the heart muscle that can weaken the heart in younger adults.

8. Where can I get an updated booster?

The updated boosters are available at many of the same sites that have been administering COVID-19 vaccines and boosters all along — pharmacies, doctor offices, community health centers, etc. You can find the closest location on vaccines.gov.

And just like with the previous COVID-19 boosters and vaccines, these shots are free.

9. Can I get it at the same time as a flu shot?

Yes. And in fact, experts are encouraging it.

“I like to say in a kind of a casual way this year, it means you’ll have to roll up both sleeves,” Schaffner adds.

Like with COVID-19, older adults are at greater risk for complications from the flu, so an influenza vaccine is a great way to reduce the likelihood that you’ll end up in the hospital. What’s more, this year’s flu season is off to a rough start, “so getting the flu vaccine will be important,” says Priya Sampathkumar, M.D., a critical care and infectious disease specialist at Mayo Clinic.

Be sure to ask for a high-dose flu shot if you are 65 or older. And while you’re at your doctor’s office or pharmacy, check with your provider to see if you’re up to date on other important immunizations, like the shingles and polio vaccines, Sampathkumar adds. Adults 65 and older should also receive a pneumococcal vaccine.

Editor’s Note: This story, originally published Sept. 6, 2022, has been updated to reflect new information.