Should you get an additional COVID-19 booster shot? How to decide.

April 1, 2022
A patient receives his second Covid-19 vaccine at UCHealth University of Colorado Hospital Anschutz on Tuesday, October 19, 2021. UCHealth experts help answer the question: should I get an additional COVID-19 booster?
A patient receives his second COVID-19 vaccine at UCHealth University of Colorado Hospital Anschutz on Tuesday, Oct. 19, 2021. Now that additional COVID-19 boosters are available for people 50 and older, should you get one? Photo by Cyrus McCrimmon, for UCHealth.

Now that additional COVID-19 vaccine booster doses are available for people ages 50 and older, you might be wondering if you should get one.

To answer your questions about the additional COVID-19 booster doses, we consulted with Dr. Michelle Barron, senior medical director of infection prevention and control for UCHealth and one of the top infectious disease experts in Colorado.

Should you get a booster dose? Which immunocompromised people are eligible for extra doses? What’s the best timing to get an additional COVID-19 booster dose?

Barron, who is also a professor of medicine and infectious diseases at the University of Colorado School of Medicine on the Anschutz Medical Campus, helps sort out the details about booster doses.

Here’s what health leaders at the U.S. Food and Drug Administration (FDA) now are recommending:

  • Anyone ages 50 and older who had their last booster dose at least four months ago is now eligible to get a second booster dose. (View information about signing up for a free vaccine dose.)
  • The new FDA authorization covers booster doses of Pfizer-BioNTech and Moderna COVID-19 vaccines.
  • Certain immunocompromised children and adults ages 12 and older also can get an additional booster dose at least four months after their last booster shot. The new guidance applies to people who have undergone solid organ transplants and others with similarly compromised immune systems.
  • Some immunocompromised people receive three doses of COVID-19 vaccines as their primary series. For these people, the additional dose will be a fifth shot.
  • For people who are not immunocompromised, the additional booster will likely be a fourth dose.
  • If you have questions about COVID-19 vaccines, check with your primary care provider to make sure you’re up to date on your doses.
  • People who received the single-dose Johnson & Johnson vaccine also are eligible for booster doses.
  • COVID-19 vaccines and booster doses are safe and highly effective, FDA and other health officials have determined.

The FDA authorized the additional booster shots because research has shown that vaccine effectiveness wanes over time. Older adults and people with compromised immune systems are at the greatest risk of getting severely ill or dying from COVID-19.

Other people who are between the ages of 50 to 64 and have comorbidities (additional illnesses) are much more likely to become severely ill and need to be hospitalized if they get COVID-19. These conditions include being obese or having diseases like diabetes. FDA leaders wanted to offer additional protection to older Americans and others who are vulnerable in case a new wave of COVID-19 infections hits the U.S. in the coming months.

Who should get additional COVID-19 booster shots now?

Barron recommends that people ages 65 and older and immunocompromised people should get additional booster shots as soon as they are eligible.

What about people ages 50 and older?

The research is less clear that healthy people between the ages of 50 and 64 need boosters immediately. If you are immunocompromised or you have other risk factors for getting severely ill with COVID-19, by all means, go ahead and get an additional booster dose. Barron said the additional doses are safe, so anyone who is eligible and wishes to get an additional dose should do so.

Why did FDA leaders approve additional COVID-19 booster doses now?

Barron said federal health officials authorized additional boosters now because they want to reduce hospitalizations and deaths as they anticipate future waves of COVID-19 infections.

“There will be another wave. The FDA is being proactive now so we can get our immune systems ready,” Barron said.

She encouraged anyone who has not been vaccinated to get a shot.

“Even if you’re getting your first vaccine dose, it’s important for you to come in. We all want to have a very free summer and do as we wish. Getting vaccines and booster doses is a way to have a good summer without getting sick,” Barron said.

What if I have already had COVID-19? Do I need vaccines or booster doses?

Yes. Even if you’ve recovered from COVID-19, it’s wise to get vaccinated and boosted.  Why? The simple answer is that you can get COVID-19 multiple times and vaccines will protect you from severe disease, hospitalization and death.

Think about other coronaviruses like the ones that cause the common cold, Barron said.

“In the winter months, some people have perpetual colds. It doesn’t matter whether you had a cold a month ago. You can get a cold again. That’s because the level of protection you get from each illness isn’t necessarily as potent as it needs to be to keep you from getting sick again,” Barron said.

“What we’ve learned from COVID-19 is that having it once doesn’t necessarily protect you from getting it again,” she said.

As for those people who are fully vaccinated and have also had COVID-19, research shows that they have built up strong immunities.

Why get vaccinated or a booster dose? Shouldn’t herd immunity protect us?

While about 80% of people in the U.S. have received at least one vaccine dose and others have recovered from cases of COVID-19, not everyone is protected. Barron said vaccines offer longer-lasting protection than natural immunities from a case of COVID-19. So she’s urging people to get both their primary vaccine doses and their boosters as soon as they’re eligible.

“With herd immunity, the thought is that the vast majority of people are protected. But there are holes in that herd and there are still individuals who are vulnerable,” Barron said.

What’s the difference in protection between first and second boosters?

Israel was the first country to start giving additional COVID-19 booster shots. The United Kingdom is also offering fourth shots now (or additional shots for immunocompromised people). Early research shows that an extra booster shot can jumpstart immunities.

“It definitely suggests that if you’re over the age of 65 or immunocompromised, getting this additional booster shot has benefits in terms of getting your immune system primed again,” Barron said.

How concerned are you about the newest omicron variant, BA.2?

The BA.2 variant is spreading quickly in Europe and cases are on the rise in the U.S. (Read more about the BA.2 variant.) So, Barron and other health experts are keeping a close eye on it.

“We’re seeing surges in the U.S. They’re not dramatic, like what we saw with omicron. It’s not something I’m losing sleep over yet, but we have to pay attention to it,” Barron said.

FDA officials approved additional COVID-19 booster doses because they expect additional waves of infections. What trends do you expect to see?

“We are feeling pretty good about where we are right now, but we could see a spike here and there,” Barron said.

The exact timing of future spikes is impossible to predict. That’s why Barron is encouraging eligible people to get vaccinated soon.

“In a couple of weeks or months, things could change and you don’t want to be behind the eight ball. Don’t wait for the next wave to happen,” she said.

She’s also reminding people that it takes about 14 days after getting a dose for the vaccine to become effective.

How soon can I get another booster shot?

The vaccines are available now. And they are free to everyone. Barron is urging everyone to come in for vaccines, whether they are receiving their first doses or their first or second booster dose.

“As soon as you are eligible, you can sign up and come in,” she said.

“It’s not too late to get your initial vaccines, your primary booster or another booster,” Barron said. “We may be over some of the biggest waves in the pandemic. But I don’t think we’re done with COVID-19. I think we’ll be continuing to manage this for years to come. So, the opportunity to start boosting your immune system and getting protected is a shot away from you.”

About the author

Katie Kerwin McCrimmon is a proud Coloradan. She attended Colorado College thanks to a merit scholarship from the Boettcher Foundation and worked as a park ranger in Rocky Mountain National Park during summers in college.

Katie is a dedicated storyteller who loves getting to know UCHealth patients and providers and sharing their inspiring stories.

Katie spent years working as an award-winning journalist at the Rocky Mountain News and at an online health policy news site before joining UCHealth in 2017.

Katie and her husband, Cyrus — a Pulitzer Prize-winning photographer — have three adult children and love spending time in the Colorado mountains and traveling around the world.