Viruses change all the time in an effort to do one simple thing: Bypass your body’s defensive immune system and make copies of itself so it can infect others and survive.
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We see this happen with influenza. And every year, we design flu vaccines that can fight off new and dominant strains of the virus to minimize its spread and the severity of symptoms associated with the flu.
Coronaviruses are no different.
New variants of SARS-CoV-2 (the original virus that causes COVID-19) have emerged. Omicron and its various offshoots — including BA.4, BA.5 and XBB.1.5 — have become particularly tricky to protect against because they’re so evasive and spread so quickly. Because of that, we’ve had to adapt our treatments for COVID-19 and design new vaccines, like a bivalent booster, to ward off the most dominant and dangerous versions of the virus.
Pediatrician Kimberly Giuliano, MD, explains how the bivalent booster is the latest in a long line of vaccines designed to keep you safe from COVID-19 infection.
What is the omicron booster?
The bivalent COVID-19 vaccine booster (also referred to as “the updated booster”) is designed to provide additional protection against COVID-19. You can get this bivalent booster from Pfizer-BioNTech or Moderna if you’ve had the “original booster” or after you’ve completed one of the following primary COVID-19 vaccine series:
- Johnson and Johnson’s Janssen.
Keep in mind that if you’re immunocompromised, the U.S. Centers for Disease Control and Prevention (CDC) has different recommendations for COVID-19 vaccines. These recommendations may require additional doses to be added to your primary series before getting an updated booster. But the point for everyone is that you finish your primary series first before getting a bivalent booster.
How is the bivalent booster different from previous COVID-19 vaccines?
The bivalent booster is the natural next step in the COVID-19 vaccination process. The bivalent booster is not a live-virus vaccine. Instead, it combines two different non-active main components — one from the original strain of SARS-CoV-2 and another from omicron variant BA.4 and BA.5 — to create one effective vaccine. The goal: Make sure your body can fight off old and current strains of COVID-19.
“Fifty percent of it is the same vaccine we’ve been getting all along and the other 50% encodes for proteins that protect us against the BA.4 and BA.5 variants,” says Dr. Giuliano.
One way to think about bivalent, or updated, boosters is to think about them like patches or updates to your favorite video game or the operating system on your computer. They’re designed to enhance the original product and build off every version that came before it. With each new layer of protection, your body adapts and learns how to fight back against a virus it otherwise wouldn’t be able to fight off.
“Our immunity has waned over time and the virus has changed over time, so it’s time to change the vaccine very similarly to what we do with the flu vaccine every year,” notes Dr. Giuliano. “This virus, like other viruses, is smart. It adapts to what it needs to survive and it has adapted that function to evade our prior vaccine immunity. So, we’re trying to keep up with the virus and provide better protection against what’s currently circulating now.”
Who’s eligible for the bivalent omicron booster?
The bivalent booster is recommended for anyone 6 months and older who’s completed their primary COVID-19 vaccination series.
Eligibility for each kind of booster depends on your age, which primary vaccination you completed and when you received the most recent COVID-19 booster.
The updated Moderna bivalent booster is available for:
- Kids 6 months through 5 years of age who’ve completed their primary Moderna vaccination at least two months prior.
- Individuals 6 and up who’ve completed any primary COVID-19 vaccination or received the most recent original monovalent booster at least two months prior.
The Pfizer-BioNTech bivalent booster is available for:
- Kids 6 months through 4 years of age who’ve completed their primary Pfizer-BioNTech vaccination at least two months prior.
- Individuals 5 and up who’ve completed any primary COVID-19 vaccination or received the original monovalent COVID-19 booster at least two months prior.
“No matter our age or health status, our protection from the original vaccine series wanes over time,” states Dr. Giuliano. “As the virus changes, updated boosters help prime our immune system so the next time we are exposed to COVID-19, our bodies are ready to combat the virus and prevent severe disease.”
Do you need the omicron booster?
With a number of COVID-19 variants floating around like XBB.1.5, a dominant subvariant, you may be wondering if it’s worth getting a bivalent booster that’s been made from other omicron variants like BA.4 and BA.5. The answer is yes, you should get a bivalent booster if you’re up-to-date on currently available COVID-19 vaccines even if you’re immunocompromised.
Early studies have shown that bivalent boosters have proven to be effective, even against the most recent strains of COVID-19, for at least three months after vaccination for people who’ve kept up with COVID-19 vaccinations.
“Prior data suggests bivalent boosters offer fairly robust protection against severe disease and hospitalization,” says Dr. Giuliano. “Time will tell whether we’ll need another booster in the future, but for now, bivalent boosters are safe and effective.”
When should you get it?
You can get the bivalent booster as early as two months after finishing your primary COVID-19 vaccination or two months after receiving the “original booster.” If you’ve recently been infected with COVID-19 but haven’t received the bivalent booster, you should wait to get the bivalent booster until you’re no longer showing symptoms.
Can you get the omicron booster with your flu vaccine?
You can get the bivalent booster and the flu vaccine at the same time. Side effects like sore/achy arms, headache or fatigue are similar for both vaccines, so it makes sense if you’d like to make two appointments to get them separately. But Dr. Giuliano recommends not putting off either appointment if you can avoid it.
“I wouldn’t recommend delaying either vaccine for very long,” she says. “And for a lot of folks, it’s more convenient to have one appointment instead of two.”