Conversation Guide: Boosters and Third Doses

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What is a booster?

Boosters are shots you get after you are fully vaccinated so that you can stay protected against COVID-19. It is important to stay up-to-date with your COVID-19 vaccines by getting a booster when you are eligible.

What is a third dose?

People with certain health conditions need more than two shots of the Pfizer (Comirnaty) or Moderna vaccine to be fully protected, because their bodies cannot build enough protection from two shots. This is uncommon.

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What is the difference between a booster and a third dose?

People with certain health conditions need more than two shots to become protected against COVID-19. People who are already fully vaccinated should have a booster when they’re eligible to make sure they stay protected.

Do boosters mean the vaccines don’t work?

COVID-19 vaccines are very effective. If you are up-to-date on your COVID-19 vaccines, you are less likely to get infected with COVID-19, get dangerously ill or die, and spread it to loved ones. 

Boosters are common for many vaccines. For example, tetanus vaccines require boosters every 10 years for adults. Scientists have found that with some vaccines a person’s protection decreases over time, and a booster helps them stay protected. The COVID-19 booster works the same way. Boosters may also broaden your protection against new variants

Are boosters safe?

Yes, boosters are very safe. Boosters have the same ingredients as the original vaccines, which have been proven safe for hundreds of millions of people. Most people who receive boosters experience the same mild side effects as they did when they got their second shot. Serious side effects are very rare, and most people who have them get better.

I am fully vaccinated. Do I need a booster?

COVID-19 vaccines protect against severe illness, hospitalization, and death. However, staying up-to-date on COVID-19 vaccines, including getting a booster when you are eligible, is important so that  you have the most protection. Scientists have found that fully vaccinated people’s protection decreases over time, and a booster helps them stay protected. In addition, boosters may help broaden your protection against new variants.

If I don’t get a booster, am I still considered fully vaccinated?

Yes, you are still considered fully vaccinated if you do not get a booster. Fully vaccinated, however, does not mean you are fully protected. For the most protection, it is important to be up-to-date on your COVID-19 vaccines. That means getting a booster shot when you’re eligible.

If I don’t get a booster, am I considered up-to-date on my vaccines?

It depends. Everyone is considered up to date until the time they are eligible for a booster – which is a few months after you are fully vaccinated.

What is the point in getting vaccinated if I will keep needing boosters?

If you are fully vaccinated, you are less likely to get dangerously ill or die from COVID-19 or spread it to loved ones. 

Boosters may give you even more protection from new variants, like Delta or Omicron. he best way to protect yourself, your family, and your community from COVID-19 is to stay up-to-date with your COVID-19 vaccines, including getting a booster when you are eligible.

I was vaccinated in another country. Can I get a booster?

If you received a vaccine that is offered in the United States (currently Moderna, Pfizer, or Johnson & Johnson), you should receive a booster a few months after your final dose to ensure that you stay protected against COVID-19. 

If you received a vaccine that is not offered in the United States but is approved by the World Health Organization (WHO), you should also receive a booster to stay protected.

If you received a vaccine that is not approved by the WHO (like Sputnik or CanSino) you should get vaccinated again in the United States. People in this situation do not need a booster because they need to be vaccinated again with a vaccine offered in the United States.

What do I do if I have more questions about boosters?

Contact your doctor, pharmacist, or another health professional if you have more questions.