Who can get a COVID-19 booster shot?

Last updated Jan. 12, 2022

COVID-19 boosters have now been approved for all adults. This is welcome news for many who are eager to get added protection against COVID-19.

To help cut through the confusion about COVID-19 vaccine booster shots, we asked infectious diseases specialist and head of Internal Medicine David Tweardy, M.D., to answer common questions.

Who can get a booster shot?

The Centers for Disease Control and Prevention (CDC) recommends that all eligible adults get a COVID-19 vaccine booster shot. The Food and Drug Administration (FDA) expanded the emergency use authorization for both the two-dose Pfizer and Moderna COVID-19 vaccine series to include booster shots for all adults. Individuals ages 18 and older can get the Moderna booster, and individuals ages 12 and older can get the Pfizer booster.

Additionally, anyone age 18 or older who received Johnson & Johnson's Janssen COVID-19 vaccine is eligible to get a booster shot.

When can I get a booster shot?

If you received the Pfizer or Moderna two-dose series, you should get a booster dose five months after you received your second dose.

If you received the single-dose J&J vaccine, you can get a booster dose two months after receiving your initial vaccine.

If I got the Pfizer or Moderna vaccine series, can I get my booster shot sooner than five months after I got my last vaccine dose? Why do I need to wait until five months after the second dose?

The mRNA vaccines provide great protection against severe COVID-19 infection, but after about five months that protection may wane a little.

There’s not a benefit to getting the booster sooner, but once you’re eligible and have reached that five-month mark, it’s time to consider getting a booster.

Are the booster shots different than the original vaccines? How will a booster help protect against the delta variant and any new, emerging variants?

The same formulation is used for all vaccine doses. The Pfizer and J&J boosters are the same dose as the original vaccines; the Moderna booster dose is half the dosage of the original vaccine.

The hope is that a booster shot will help amp up your body’s immune response so it can better protect against COVID-19, even as new variants emerge.

Earlier this year, we heard a lot about third doses of COVID-19 vaccine. Are booster shots and additional doses the same thing?

Not exactly. In August, additional COVID-19 doses – also called third doses – became available for moderately and severely immunocompromised individuals. This is a third dose that comes after the initial two-dose vaccine series of the for Pfizer-BioNTech’s or Moderna vaccine for people who may not have mounted a strong enough immune response after receiving the initial vaccine series. Since these individuals have weakened immune systems, they need that third dose to protect against COVID-19 since they may not have had the same level of protection against COVID-19 as other people.

A booster dose, on the other hand, is a subsequent dose given months after the initial vaccination to reinvigorate the immune system. Booster doses are intended for people whose immune response against COVID-19 may have decreased over time.

How long do I need to wait between my booster and other vaccines, such as the flu vaccine?

There’s no need to space out your booster shot and flu vaccine. The CDC says you can safely get other vaccines without regard to timing with the COVID-19 vaccine.

This flu season is expected to be a bad one, and we are still dealing with the highly transmissible delta variant. So, it’s important to get both your flu vaccine, and, if you’re eligible, COVID-19 booster as soon as possible.

When will I need another booster after this?

Researchers are looking closely at the data on vaccines, but it is not yet known whether more booster shots will be needed in the future.

How long after I get the booster will it take until I have the maximum protection against COVID-19?

You'll have full protection about two weeks after you receive the vaccine booster dose.

What if I don’t get the booster – or I wait to get one? What are the risks?

Immunity to COVID-19 has been shown to wane a little bit over time. That means you’re potentially at increased risk for getting a COVID-19 breakthrough infection.

Getting your booster shot once you’re eligible will play a vital role in reducing your risk of COVID-19. The delta variant has shown us that we can’t let our guards down and need to do everything we can to protect ourselves and each other – including immunocompromised individuals like our cancer patients at MD Anderson.

Do I need to get the same vaccine for the booster that I got for the first two doses? And do I need to get it at the same place I got the first two doses?

For those who are eligible for a booster, you have the option to receive any of the three boosters (Moderna, Pfizer or J&J). However, it's best to talk to your health care provider to weigh the risks and benefits of mixing and matching vaccines.

You do not need to get your booster at the same place you got the first two doses. But make sure you take your vaccination record with you when you get vaccinated to show which vaccine you received originally and when.

Does MD Anderson offer booster shots?

Yes. MD Anderson patients can schedule a Pfizer or Moderna booster shot through MyChart. Family members and members of the community can schedule a COVID-19 booster online.

MD Anderson does not have a supply of J&J vaccines at this time.

Will I have to keep masking and social distancing once I get a COVID-19 booster?

For now, it is important to continue masking and physical distancing even after you get a booster. But the hope is that as more people get vaccinated and get boosters, it will be safe to ease up on some of these precautions.

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