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Pfizer vaccine booster now part of FDA mix and match: What to know

Pfizer's vaccine booster shot is now available to millions of Americans, including anyone 65 and older, and can be mixed and matched as a booster with Moderna and Johnson & Johnson shots.


A Pfizer COVID-19 vaccine booster is approved for certain groups who received the second dose at least six months ago.

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For the most up-to-date news and information about the coronavirus pandemic, visit the WHO and CDC websites.

The Pfizer-BioNTech vaccine booster shot is already approved by the Centers for Disease Control and Prevention. Now, the Food and Drug Administration said anyone who is eligible for a COVID-19 booster shot can mix and match Pfizer's vaccine with Moderna and Johnson & Johnson. Those two received authorization by the FDA this week.

Multiple studies show that the effectiveness of vaccines may start to decline after six to eight months, but recent studies say a booster dose of Pfizer shows 95.6% efficacy against COVID-19.

Over the summer, as the delta variant took hold in the US, the number of cases, hospitalizations and deaths from COVID-19 surged. The vaccines that are approved by the FDA have proven to be highly effective in preventing hospitalization. Those who remain unvaccinated account for nearly all hospitalizations and deaths -- over 97% as of July. With the new federal vaccination mandates, the Biden administration aims to counter the surge and put pressure on anyone who hasn't gotten the shot

We'll explain below who is now eligible for the Pfizer booster shot. For more on COVID-19, here's what we know about COVID-19 vaccine for kids, the latest guidance on masks and breakthrough infections. And here's what you should know about the new federal COVID-19 vaccination mandates -- and what to do if you lost your vaccine card.

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Who is eligible for the Pfizer booster shot?

A single dose of the Pfizer-BioNTech vaccine booster is available to those age 65 and older, nursing-home residents and those age 50 to 64 with underlying medical conditions. Here's who the CDC said is eligible for a Pfizer booster shot:

  • Individuals 65 years of age and older and residents in a long-term facility should receive a booster.
  • Individuals 50 through 64 years of age with an underlying medical condition should receive a booster.
  • Individuals 18 to 49 years of age with an underlying condition may receive a booster if they assess their risk of infection as high.
  • Individuals 18 to 64 years who are at increased risk because of their job -- such as hospital workers, teachers or grocery store workers -- may receive a booster if they assess their risk of infection as high.

What about mixing and matching the COVID-19 booster shot?

The CDC said those who qualify for a booster can get any of the three available -- the one from Pfizer, Moderna or Johnson & Johnson -- no matter which one they received first. The CDC will have more details shortly on its mix-and-match plan.

When can I get the Pfizer booster shot?

Now, if you're eligible. According to White House Coronavirus Response Coordinator Jeff Zients, up to 20 million people received their second dose of the Pfizer vaccine at least six months ago and are eligible for the Pfizer booster shot now.

State and local health officials have started to roll out campaigns to help the public better understand who qualifies immediately, according to the New York Times

What is an 'underlying medical condition'?

The CDC said adults of any age can be more likely to get severely ill from COVID-19 with an underlying medical condition. Here are what the CDC lists as underlying conditions:

  • Cancer
  • Chronic kidney disease
  • Chronic lung diseases
  • Neurological conditions, such as dementia
  • Diabetes
  • Down syndrome
  • Heart conditions
  • HIV infection
  • Liver disease
  • Overweight
  • Pregnancy and recently pregnant
  • Sickle cell disease or thalassemia
  • Smoking, current or former
  • Solid organ or blood stem cell transplant
  • Stroke or cerebrovascular disease
  • Substance use disorders
  • Weakened immune system

Outside of the underlying conditions, the CDC said older adults are more likely to get severely ill from COVID-19.

Why would I need a Pfizer booster shot?

If you're fully vaccinated, the CDC says you will continue to be protected from infection and especially against serious illness. All the COVID-19 vaccine shots authorized by the FDA continue to be "highly effective in reducing risk of severe disease, hospitalization and death," according to the CDC.

However, studies -- such as one from Israel and another from the UK -- suggest that the effectiveness of COVID-19 vaccines may decrease after six or eight months, necessitating a booster shot to maintain high levels of protection against breakthrough COVID-19 infections.

Pfizer released data from its application to the FDA, arguing that immunity wanes over time and that administering boosters is a way to get ahead of the curve and contain the pandemic. Pfizer also presented what it considers proof that a booster will be safe and effective for the majority of adults. 

What is the controversy around COVID booster shots?

President Joe Biden said he wants everyone in the US who is already fully vaccinated to be eligible for a booster shot. The FDA, however, said that data needs to be reviewed more thoroughly by experts before opening up boosters to everyone. Instead, the FDA recommended that those who are age 65 and older should be eligible, as well as those who are at a high risk of severe COVID-19 symptoms -- that includes frontline and health care workers. The CDC decision follows the FDA recommendation.

The tension over who should get boosters remains high. Most recently, leading scientists argued in the medical journal The Lancet that carrying out a widespread distribution of booster shots is not appropriate at this time

Meanwhile, Dr. Tedros Adhanom Ghebreyesus, director-general of the World Health Organization, has called for a moratorium on booster doses until every country is able to vaccinate at least 40% of its population. "I will not stay silent when the companies and countries that control the global supply of vaccines think the world's poor should be satisfied with leftovers," Tedros said.

White House Press Secretary Jen Psaki has repeatedly said having enough boosters for the US does not reduce the number of vaccines the US supplies to other countries. "We feel that it's a false choice and that we can do both," Psaki said in August, adding that the US has donated more vaccines globally than all other countries combined.

At a COVID-19 White House briefing on Sept. 17, Zients said that the US has distributed 140 million vaccine doses to almost 100 countries, and that it had purchased 500 million Pfizer doses to donate to the countries most in need in order to accelerate a global exit from the pandemic. 


Already vaccinated? A booster could be in your future.

Sean Booker/CNET

Who had already been eligible to get a Pfizer or Moderna booster shot?

Some immunocompromised people are already eligible under guidelines from the CDC and can go out now to get their third dose. The CDC's booster recommendation is for those 12 and older for the Pfizer vaccine. For the Moderna vaccine, the FDA authorized a single booster dose for individuals who are 65 years and older, those 18 to 64 years old at high risk of contracting a severe case of COVID-19, and those ages 18 to 64 "with frequent institutional or occupational exposure" to the coronavirus.

A booster dose of the Johnson & Johnson vaccine can be administered at least two months after individuals 18 and older receive the initial dose.

The CDC recommends that you talk with your health care provider about your medical condition and whether an additional dose is appropriate. See our guide to the booster vaccine for more on a booster shot for moderately to severely immunocompromised people.

Is the Pfizer booster the same as the first two shots?

Yes. According to Pfizer, its COVID-19 booster would be a third jab of the same vaccine you got with the first two doses. 

Pfizer is working separately with its partner BioNTech on a version of the COVID-19 vaccine that targets the delta variant.

Where can I get a booster shot?

According to Zients, boosters will be available at roughly 80,000 places across the country, including over 40,000 local pharmacies. Some 90% of Americans have a vaccine site within 5 miles of where they live, Zients said, and getting a booster shot will be just as easy as getting the first shot. And the booster shot will be free too. 

You can check to see which vaccines are available where or call 1-800-232-0233 for vaccine information.

For more on coronavirus treatments and vaccines, here's what we know about monoclonal antibody treatments, the new federal vaccine mandates and why some people may not want the shot.

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.