Omicron Boosters: More Encouraging Data Emerges Around the Same Time as a New Variant

What’s happening

Updated COVID boosters from Pfizer and Moderna are available to everyone 6 months and older. Some adults can get Novavax for a booster instead.

Why it matters

As the virus mutates, boosters have become necessary to restore protection given by the original vaccines or past infections.

What’s next

Viruses like COVID-19 spread really well indoors. OIder adults in their 60s and up, as well as younger folks with medical conditions, remain the most vulnerable to severe disease or death and will especially benefit from a booster dose.

New, real-world data from Israel confirms that the new COVID-19 vaccines formulated to work against the omicron variant are effective at keeping people out of the hospital, according to findings posted by The Lancet. The study, which hasn’t yet been peer-reviewed, included information from more than 600,000 people age 65 and older. 

This real-world data backs up earlier information from the US Centers for Disease Control and Prevention, which found that in November 2022, monthly hospitalization rates for adults who were vaccinated but didn’t get an updated booster were 2.7 times higher compared to adults who did get a new booster. The rate of hospitalization in unvaccinated adults was 16 times higher compared to adults who got a new booster. 

Most adults in the US are vaccinated against COVID-19, but a much smaller number have received the bivalent adult booster — about 18%, according to CDC data. Health officials are raising their volume on the call especially to older adults in their 60s and up, who are much more likely to die from COVID-19 or get really sick from it. People over age 65 have made up at least 81% of all deaths from COVID-19, according to the CDC. 

In a November briefing with the White House COVID-19 Response Team, Dr. Anthony Fauci, who retired from his government posts last month, explained that the reason we need boosters is because the virus that causes the disease is different than other diseases, like measles, that don’t have the same immune-escaping capabilities. Updated boosters, like the bivalent ones made by Pfizer-BioNTech and Moderna, restore immunity that’s waned from an earlier vaccine or COVID-19 infection. 

“There are two issues that in some respects are unprecedented when it comes to infectious diseases,” Fauci said. “And that is: As good as the vaccine is and as good as post-infection protection is, the immunity and protection wanes over time.”

“If you get vaccinated with measles or infected with measles, the duration of protection is measured at a minimum in decades and likely for a lifetime,” Fauci added. “That just happens to, unfortunately, not be the case when you’re dealing with coronavirus and particularly SARS-CoV-2. So you need to update the protection that we know is good protection.”

Updated or not, boosters have reduced the risk of hospitalization and death from COVID-19 across age groups. Even as new versions of omicron — like XBB.1.5 — emerge, some lab studies give scientists believe that the bivalent boosters will still prove effective.

Adults who haven’t gotten the new booster yet have options: You can choose either Moderna’s or Pfizer and BioNTech’s bivalent formulas. Adults who don’t want either might be able to get Novavax as a booster instead. 

Here’s what we know.

Vaccine needles arranged on a black table.

Sarah Tew/CNET

What we know about the bivalent vaccines

The bivalent formulas made by Moderna and Pfizer-BioNTech target both the “original” version of COVID-19, as well as the BA.4 and BA.5 subvariants of omicron. The FDA has authorized boosters from Pfizer-BioNTech and Moderna. Pfizer’s is for those age 5 and older, and Moderna’s is for people 6 and up. 

When they were authorized by the FDA, the agency made its decision based on clinical trials of a slightly different bivalent booster that targets the BA.1 version of omicron instead of BA.4/BA/5. In addition, there were mice studies on the BA.4/BA.5 formula. While this approach was previously unprecedented in the COVID-19 vaccine campaign, health officials say it’s not too far off the way we approve influenza vaccines. Every year, the flu vaccine is tweaked with a strain believed to be the best target. And the new COVID-19 boosters also do not introduce any new vaccine ingredients.

“Bivalent and multivalent vaccines are very common and modifying a vaccine to include different virus strains often does not require a change in other ingredients,” FDA Commissioner Dr. Robert M. Califf said in August in a tweet. “FDA has extensive experience with reviewing strain changes in vaccines, as is done with the annual flu vaccine.” 

In addition to the real-world findings from thousands of patients in Israel, and confirming data from the CDC, there have been earlier announcements about how the bivalent boosters shape up on earlier versions of omicron compared to the original vaccine. (XBB.1.5, BQ.1 and BQ.1.1 make up most COVID-19 cases currently — not BA.5). Moderna announced positive results in November on its clinical trial with its new bivalent booster. In the largest trial to date on the updated bivalent vaccines, the company said that a booster dose of the new, bivalent vaccine “induced significantly higher neutralizing antibody titers against BA.4/BA.5,” compared with the original booster. The same month, Pfizer and BioNTech announced promising results of its updated booster dose in older adults, reporting that adults older than 55 had a four times greater immune response compared with the original booster. The safety profile of Pfizer’s and Moderna’s new boosters were similar to their original vaccines, the companies said. 

An early analysis also showed Moderna’s updated vaccine gave a “robust” antibody response against BQ.1.1, the company said — a subvariant of omicron which has now surpassed BA.5 — though less robustly when poised against BA.5. 

Who can get Novavax’s booster? 

Adults who’ve been vaccinated against COVID-19 — but haven’t yet received any booster — can get a dose of Novavax as their booster. It doesn’t matter which vaccine you originally received — Pfizer, Moderna, Johnson & Johnson or Novavax. 

Read more about the Novavax vaccine here

When should I get the updated booster? 

The updated mRNA boosters (from Pfizer and Moderna) are authorized by the FDA for adults who’ve gone at least two months since their last vaccine dose, whether it was a booster shot or a primary series. It doesn’t matter which vaccine you originally received, and it shouldn’t matter which brand you choose now. Moderna’s new booster, like its previous vaccine, is a slightly larger dose (50 micrograms) than Pfizer’s (30 micrograms). 

For babies, toddlers and preschoolers who are eligible for smaller doses of the updated formulas, it’s a little different. Children 6 months through 5 years who got Moderna’s primary series vaccine can only get an updated dose of Moderna at least two months after their second shot. Children 6 months through 4 years who started Pfizer’s primary series can get the bivalent vaccine as their third dose, instead of the “original” third dose. Children in this age group who already got three doses of Pfizer aren’t eligible for an updated booster right now.

If you’re 18 or older and were vaccinated earlier in the pandemic but haven’t gotten any booster yet, you can get a Novavax shot at least six months after finishing your primary series if you prefer it over an mRNA vaccine.

If you’re in your 60s or older — or even if you’re in your 50s — the advice among medical experts is clear: Get the updated booster as soon as you can. Older adults are more vulnerable to severe illness and death from COVID-19. If you’re younger and have a medical condition that makes you more vulnerable to severe disease, including diabetes, heart disease and more, you could also especially benefit from the boost in protection against severe illness.

Health officials have encouraged everyone to get their updated boosters, and Moderna and Pfizer-BioNTech have authorized formulas for children as young as 5. However, on an individual level, timing advice for people who very recently had COVID-19 (we’re talking within the last few months, not last year) isn’t quite as cut-and-dry as it is for higher-risk adults, or people who are several months out from their last bout of COVID-19. 

At a panel meeting of the CDC’s scientific advisers, a committee that meets before the CDC recommends a vaccine, a few members expressed concern that some people would be better off waiting longer than two months between their last shot and this new booster, especially people who have recently had COVID-19 and still have relatively high immunity. (In its general vaccine guidance, the CDC says that people can wait three months before getting the shot if they’re getting over COVID-19.) 

And while myocarditis is rare overall, younger men and teenage boys appear to be at higher risk post-vaccination and waiting longer between vaccine doses appears to reduce this risk. 

From an immune response perspective, some infectious disease doctors have suggested waiting as long as four to six months between your last COVID-19 infection or vaccine to get the most bang out of the new booster. Fauci told PBS that if you tested positive for COVID-19 recently, “you should wait about three months, at least three months from the time that you had a prior infection” before getting the new booster. Fauci added that because he had COVID-19 in the middle and end of June, he was waiting until the end of September to get boosted.

Fauci ended up getting his booster live on The Late Show With Stephen Colbert in early October.

But individual immunity is only one piece of the puzzle, when we’re talking about a respiratory virus as contagious as COVID-19. People who may only have very mild symptoms they dismiss as a cold or allergies can still pass along an infection to their more-vulnerable family or friends.

“Even if you yourself are on the low-risk side, you’re going to have family and friends you’re going to see,” Dr. Ashish Jha, the White House COVID-19 Response Team Coordinator said on Andy Slavitt’s podcast in October, as reported by CNBC

“You don’t want to be the person who gives it to your grandma.” 

Dr. Jayne Morgan, executive director of the COVID Task Force at Piedmont Healthcare, said that it’s important to get a booster right now so we can “stem the tide” on the pandemic.

“You want to have this booster while omicron is circulating. The whole point of bringing the booster out now is so that we can stop chasing this variant,” Morgan said, adding that it’s unclear what variants or subvariants will be in our future, and if (or how much) they’ll evade our protection from vaccines, infections and treatments. 

The vaccines and boosters have proven to be especially effective at preventing severe disease in older adults. A report published Oct. 7 by the US Department of Health and Human Services found that COVID-19 vaccines were linked to about 650,000 fewer hospitalizations and 300,000 fewer deaths in seniors and other people who are enrolled in Medicare in 2021. More than 81% of COVID-19 deaths occur in people over age 65, according to the CDC. 

Where can I get the new booster? 

You should be able to use the vaccine finder site Vaccines.gov to find an updated vaccine near you. When you’re choosing your updated booster from either Pfizer-BioNTech or Moderna, make sure to select the shot that says “Newly Authorized Bivalent” in bold text. Primary series vaccines, or the first two doses, are still available for people who haven’t received any vaccine yet.

Smaller doses of the original vaccines are also still available for kids as young as 6 months. For those who are getting the Novavax booster, you’ll find it under “Primary vaccines.” 

Can I get a flu vaccine at the same time as my booster? 

Yes, according to the CDC. There’s no recommended waiting period between the seasonal flu shot and the COVID-19 vaccines.  

So far, the current flu season has been the most severe since the 2010-2011 flu season. 

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.