Which Is the Best COVID-19 Booster Shot: Pfizer, Moderna, or Novavax

The first COVID-19 vaccines were authorized in December 2020. Fast forward several years later, there's been a world of change. Three different COVID vaccines are authorized or approved for use, vaccines are widely available at pharmacies across the U.S., and millions of doses have been administered.

The Pfizer, Moderna, and Novavax COVID vaccines can all be used to keep you and your family up to date with your vaccinations. These vaccines initially targeted the original strain of the virus, but updated versions are now available. The updated Pfizer and Moderna shots target an Omicron subvariant called KP.2, while the updated Novavax vaccine targets one called JN.1. These vaccines aim to offer more protection against current viral variants that are making people sick.

Still, with new information, data, and recommendations coming from many different sources, it's hard to know what to do for your next shot. Ever-changing guidelines can be tough to digest, too. So, you may be thinking: "What do I really need to know about which vaccine is best for me?"

Who is eligible for a COVID booster shot?

Staying up to date with COVID vaccines is important because protection from the vaccines can lessen over time. Vaccine effectiveness can also change in response to different variants that are circulating around the world. A COVID booster shot can help improve your protection against current versions of SARS-CoV-2, the virus that causes COVID.

At this time, everyone ages 6 months and older in the U.S. is eligible to get an updated, 2024-2025 COVID vaccine ("booster shot"). However, if you've recently had COVID, you can delay getting an updated 2024-2025 vaccine for 3 months.

Good to know: The vaccine recommendations for people are immunocompromised may be different, including recommendations for extra doses. Check with your primary care provider for eligibility and timing.

Adults and children ages 5 years and older

People who are at least 5 years old can receive one dose of an updated Pfizer or Moderna vaccine. This is true no matter your COVID vaccination history.

If you've received one or more COVID vaccine doses in the past, you can receive an updated, 2024-2025 vaccine if it's been at least 2 months since your last dose. If you've never received a COVID vaccine before, you can receive one dose at any time.

What's more, people who are at least 12 years old have the option to receive an updated 2024-2025 Novavax vaccine instead. You may need 1 or more doses, depending on your vaccination history:

• If you've received any number of Pfizer or Moderna doses in the past (or 2 previous Novavax doses), you can receive 1 Novavax dose if it's been at least 2 months since your last COVID vaccine.

• If you've only received 1 Novavax vaccine so far (and no other COVID vaccines), you can receive another Novavax dose 3 weeks after the first one.

• You can receive 2 Novavax doses, spaced 3 weeks apart, if you've never received a COVID vaccine before.

Good to know: It's not currently recommended for adults ages 65 and older to receive additional 2024-2025 vaccine doses, unless you're immunocompromised. Vaccine recommendations that apply to younger adults also apply to older adults.

Kids ages 6 months through 4 years old

Children ages 6 months through 4 years old can also receive an updated 2024-2025 vaccine. Some kids may qualify for more than one dose, too. This is summarized below.

Kids ages 6 months through 11 years old with a weakened immune system are another exception. Depending on their vaccination history, they may be able to receive 1, 2, or 3 updated Pfizer or Moderna doses. Their pediatrician can determine the best path forward.

Does your COVID booster shot need to be the same as your original vaccine?

Yes and no.

Kids ages 6 months through 4 years old should generally stick to the same COVID vaccine brand. But people ages 5 years and older can make the choice to switch up which vaccine they receive. The FDA and CDC allow a "mix-and-match" approach for COVID booster shots in this older age group. This means that regardless of the vaccine that you received first, you can choose the vaccine that you want next.

For example, if you received a Pfizer COVID vaccine in the past, you can choose which vaccine you want for your next dose. You could decide to get Pfizer again, or you could choose to get Moderna or Novavax.

That said, the Johnson & Johnson (J&J) COVID vaccine should not be used. It's no longer available in the U.S. for any purpose.

Are COVID booster shots the same as the original vaccine?

No. The original vaccines targeted the original strain of SARS-CoV-2. This is the strain that was first discovered in 2019.

For 2024-2025, the Pfizer and Moderna booster shots target an Omicron subvariant called KP.2. The updated Novavax vaccine targets JN.1. Omicron subvariants like these have been predominant in the U.S. for months.

For context, during the 2023-2024 respiratory illness season, the Pfizer, Moderna, and Novavax vaccines targeted a different Omicron subvariant (called XBB.1.5).

What risks are associated with COVID boosters?

Research has shown that COVID booster shots can help provide additional protection against COVID.

But that doesn't mean they're free of any risks. Risks of COVID booster shots resemble the risks of previous vaccine doses. These can include:

• Common side effects: COVID booster shot side effects seem to be similar to side effects you may have felt from your initial dose(s). This can include tiredness, fever, and pain or swelling where you received the shot.

• Heart concerns: The Pfizer, Moderna, and Novavax vaccines have been connected to myocarditis (heart inflammation) and pericarditis (heart lining inflammation). These side effects are rare, though.

Researchers will continue to study the effects of COVID vaccines.

Does it make a difference if you're pregnant or nursing?

No, if you're pregnant or nursing, both the CDC and American College of Obstetricians and Gynecologists recommend receiving a booster shot when you're eligible.

Which booster should you get?

The CDC doesn't recommend one updated 2024-2025 COVID vaccine over the other. People ages 12 and older can choose to receive the updated Pfizer, Moderna, or Novavax vaccine. Children under 12 can choose between the updated Pfizer and Moderna vaccines. But for children under 5 years old, the choice usually depends on the primary vaccine series they initially received.

To help narrow down your choice between the three, you should weigh your options when deciding what course of action is best for you. You can also talk to your healthcare professional for their recommendation on your individual situation.

If you don't feel strongly about one vaccine, the best move is to get a booster as soon as you can. Differences between the vaccines - especially when it comes to Pfizer and Moderna - are small and nuanced. The best shot is the one that you have access to.

But there are still a few thoughts to consider when making this decision. A summarized list of considerations are detailed below.

Sticking with the same vaccine

If you want your booster shot to be the same as your original vaccine, there's logic to back up your decision.

For one, vaccine recommendations are complex and change frequently. With some exceptions, a safe move may be to stick with the same vaccine that you got originally.

Researchers are continuing to conduct studies that look at how effective the same vaccine is over time. For example, it makes sense for Pfizer to see how effective their updated vaccine is following previous dose(s) of their own vaccine. They're less likely to research how effective the Moderna shot is following a few doses of a Pfizer vaccine. However, some researchers have conducted "mix-and-match" effectiveness studies.

Changing to a different vaccine

If you want your booster shot(s) to be different from your original vaccine, that would also make sense.

If you originally received the Pfizer vaccine, switching to the Moderna vaccine has been shown to result in a good immune response. The same goes for switching to Pfizer if you originally got Moderna. Some "mix-and-match" studies have found that getting a different booster may even lead to a slightly better immune response than getting the same vaccine again. However, the data isn't fully clear. There isn't a clear advantage to switching between the Pfizer, Moderna, and Novavax vaccines.

If you originally received the J&J vaccine, then you should switch to a different vaccine for your next dose(s). The J&J vaccine is no longer authorized for use.

Other considerations

Effectiveness data changes frequently. Based on current vaccine effectiveness data, you may be inclined to choose one vaccine over another. New studies about vaccine effectiveness come out many times a month.

The most up-to-date information may be helpful when deciding if you want to get a different vaccine from what you got originally. When it's time to get your booster dose, try to look around and see what vaccine is best supported at the time. If you aren't sure, ask a healthcare professional.