Vaccine Booster Doses

Content last updated June 27, 2022

The Center for Disease Control and Prevention (CDC) and the Western States Scientific Safety Review Workgroup’s updated booster dose recommendations are as follows:

  • Children ages 5-11 should receive a booster dose five months after completing their primary vaccine series. Immunocompromised children should receive their booster at least three months after their primary series.
  • Everyone 12 and older should receive a booster dose five months after completing their primary vaccine series, or two months after receiving the single-shot Johnson & Johnson (J&J) vaccine.
  • Everyone 50 and older should receive a second booster dose four months after receiving their first booster dose.
  • Individuals 12 and older who are moderately or severely immunocompromised should receive a second booster dose four months after receiving their first booster dose.
  • Those 18 and older who received a primary vaccine and booster dose of the J&J vaccine four months ago can receive a second booster dose of an mRNA COVID-19 vaccine.
If you received... Who should get a booster When to get a booster Which booster to get Can I get a second booster?
Pfizer-BioNTech People 5 years and older At least 5 months after completing the primary series

Pfizer or Moderna are preferred*

Everyone 50 and older and certain immunocompromised individuals 12 and older should receive an additional booster dose of an mRNA COVID-19 vaccine if 4 months or more have passed since their last booster dose.
Moderna People 18 years and older At least 5 months after completing the primary series Pfizer or Moderna are preferred* Everyone 50 and older and certain immunocompromised individuals 18 and older should receive an additional booster dose of an mRNA COVID-19 vaccine if 4 months or more have passed since their last booster dose.
Johnson & Johnson People 18 years and older At least 2 months after completing the primary series Pfizer or Moderna are preferred*

Everyone 50 and older and certain immunocompromised individuals 18 and older should receive an additional booster dose of an mRNA COVID-19 vaccine if 4 months or more have passed since their last mRNA booster dose.

Everyone 18 and older who received a primary vaccine and booster dose of Johnson & Johnson’s Janssen COVID-19 vaccine at least 4 months ago should receive a second booster dose using an mRNA COVID-19 vaccine.

*mRNA vaccines are preferred, but the Johnson & Johnson COVID-19 vaccine is still available if you aren't able or willing to get another vaccine.

Doses for Immunocompromised

If you are moderately or severely immunocompromised, guidelines will vary.

If you got… Should I get an additional dose? Can I get a booster? Total doses
Pfizer: Two doses administered 21 days apart for ages 5 and older Yes, people age 5+ who are moderately or severely immunocompromised should get an additional dose 28 days after their 2nd shot.

Yes, a Pfizer mRNA booster is recommended 3 months after the last dose to be up to date for those aged 5-11.

A 2nd mRNA booster is not recommended for those aged 5-11.

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Yes, an mRNA booster is recommended 3 months after the last dose to be up to date for those ages 12 and older.

A 2nd mRNA booster should be received 4 months after the 1st booster for those 12 and older.

5
Pfizer: Three doses administered for children 6 months through 4 years old. The first two doses are to be administered 21 days apart and the third dose 8 weeks after the second dose. No, children 6 months through 4 years old who are moderately or severely immunocompromised should not receive an additional primary dose at this time. No, an mRNA booster is not recommended for children 6 months through 4 years old at this time. 3
Moderna: Two doses administered 28 days apart for ages 6 months and older Yes, people aged 6 months and older who are moderately or severely immunocompromised should get an additional dose 28 days after their 2nd shot.

No, an mRNA booster is not authorized for those 6 months through 17 years old at this time for those who received Moderna as their primary series.

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Yes, an mRNA booster is recommended 3 months after the last dose to be up to date for those 18 years and older.

A 2nd mRNA booster should be received 4 months after the 1st booster for those 18 and older.

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Johnson & Johnson: One dose, authorized for ages 18 and older Yes, people age 18+ who are moderately or severely immunocompromised should get an additional dose with mRNA vaccine 28 days after 1st dose of J&J.

Yes, an mRNA booster is recommended at least 2 months after the last dose for those aged 18 and older to be up to date.

If you received a primary and booster dose of J&J, a 2nd booster of mRNA vaccine should be received 4 months after the 1st booster.

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Frequently Asked Questions

Do I have to get the same vaccine brand for my booster dose?

You can get a different vaccine for your booster dose than the vaccine you got for your primary series. The CDC made their decision following a careful review of the latest data (Moderna, Johnson & Johnson, mix and match boosters), and robust and deliberative discussion around booster shots.

Why are booster doses Important?

Booster doses will help provide continued protection against severe disease. Booster doses were previously recommended only for populations at high risk for severe COVID-19, but the recommendation expanded to include everyone 5 years and older to help increase protection against COVID-19 illness. This is especially important with the rise of more contagious variants and cases of COVID-19 increasing across the United States.

The COVID-19 vaccines authorized or approved in the United States are still very effective at reducing the risk of severe disease, hospitalization, and death from COVID-19, even against variants. Still, the current vaccines may be associated with a drop in protection over time. Booster doses will increase vaccine-induced protection against COVID-19 and help immunity last longer.

Are you still vaccinating people with the primary series?

Yes. Getting everyone who is eligible vaccinated with a primary series is still a top priority. Hospitalization rates are 10 to 22 times higher in unvaccinated adults compared to vaccinated adults. People who are vaccinated are significantly less likely to get seriously sick (or sick at all) from COVID-19, compared to those who are unvaccinated. Vaccinations can also help prevent individuals from getting ill and developing the long haul symptoms reported by up to 50% of those who become ill from COVID-19.

If we need booster shots, does that mean that the vaccines aren't working?

No. The current COVID-19 vaccines we have in the U.S. are working well to prevent severe illness, hospitalization, and death, even against variants. However, public health experts are seeing reduced protection against mild and moderate COVID-19 illness, especially among high-risk populations.

If I don't get a booster dose, am I still fully vaccinated?

A person is fully vaccinated two weeks after receiving all recommended doses in the primary series of their COVID-19 vaccination.

A person is up to date with their COVID-19 vaccination if they have received all recommended doses in the primary series and all boosters when eligible.

How do I show that I'm eligible for a booster dose?

You can self-report that you are eligible for a booster dose. You do not need to show a recommendation from a health care provider.

Please take your vaccination card to your booster dose appointment so the provider can first confirm that you've completed the entire primary vaccine series. If you don't have your card, the provider can look up your record.

What’s the difference between an additional vaccine dose and a booster vaccine dose?
  • An additional dose is for patients who completed a primary mRNA vaccine series (Pfizer or Moderna) but did not have a strong enough immune response. 
  • A booster dose is for patients when it’s likely that their immunity after the initial vaccine series waned over time.

The following groups are currently recommended to get a booster dose of COVID-19 vaccine.

  Who Gets It When to Get It
Additional dose People who are immunocompromised and got a two dose mRNA COVID-19 vaccine. At least 28 days after your final dose of mRNA COVID-19 vaccine or your first dose of Johnson & Johnson vaccine. The additional dose after J&J must be an mRNA vaccine.
Booster dose People 18 years and older who got the Johnson & Johnson COVID-19 vaccine as their primary series.

At least two months after your first dose.

For patients who are moderately to severely immunocompromised, at least 2 months after your additional (2nd) dose.

People 5 years and older who got the Pfizer-BioNTech COVID-19 vaccine as their primary series.

At least 5 months after your final dose of an mRNA vaccine.

For patients who are moderately to severely immunocompromised, at least 3 months after your additional (third) dose.

People 18 years and older who got the Moderna COVID-19 vaccine as their primary series.

At least 5 months after your final dose of an mRNA vaccine.

For patients who are moderately to severely immunocompromised, at least 3 months after your additional dose.

People over the age of 50, and certain immunocompromised individuals, may now receive an additional booster dose of mRNA COVID-19 vaccine if 4 months or more have passed since their last booster dose. Following FDA’s regulatory action, the Western States Scientific Safety Review Workgroup has weighed in to align with updated Centers for Disease Control and Prevention recommendations on additional booster doses.

What does it mean to be immunocompromised?

The U.S. Food and Drug Administration (FDA), Advisory Committee on Immunizations Practices (ACIP), and Western States Scientific Safety Review Workgroup recommend a third dose of vaccine for moderately to severely immunocompromised people ages 5 and older. 

If you have any of the following medical conditions you are considered moderately to severely immunocompromised and may benefit from an additional dose of COVID-19 vaccine. This includes people who:

  • Are receiving active cancer treatment for tumors or cancers of the blood
  • Received an organ transplant and are taking medicine to suppress the immune system
  • Received a stem cell transplant within the last 2 years or are taking medicine to suppress the immune system
  • Have moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
  • Have advanced or untreated HIV infection
  • Are receiving active treatment with high-dose corticosteroids or other drugs that may suppress the immune response.

While the vaccines we have are 90% effective against most virus variants, studies show that moderate to severely immunocompromised individuals do not always build strong immunity. The third dose is not considered a booster, but an additional dose for those who did not develop adequate immunity with the two-dose series.

If you got an mRNA vaccine (Moderna or Pfizer) and are moderately to severely immunocompromised:

  • You should get your additional dose at least 28 days after your second dose.
  • If possible, you should get the same brand of vaccine as your first two doses. If that brand is not available, you may get the other mRNA vaccine brand.
  • You should also receive a single COVID-19 booster dose (Pfizer-BioNTech, Moderna or Janssen) at least 3 months after completing your third mRNA vaccine dose.
  • You may also receive a second booster dose of Pfizer-BioNTech COVID-19 vaccine if you are 12 years of age and older with certain kinds of immunocompromise at least 4 months after receipt of a first booster dose of any authorized or approved COVID-19 vaccine.
  • You may also receive a second booster dose of Moderna COVID-19 vaccine if you are 18 years of age and older with certain kinds of immunocompromise at least 4 months after receipt of a first booster dose of any authorized or approved COVID-19 vaccine.

If you got the Johnson & Johnson (Janssen) vaccine and are moderately to severely immunocompromised:

  • You should get a single COVID-19 booster vaccine (Pfizer-BioNTech, Moderna or Janssen) at least 2 months (8 weeks) after your initial Janssen primary dose.
  • Adults who received a primary vaccine and booster dose of Johnson & Johnson’s Janssen COVID-19 vaccine at least 4 months ago may now receive a second booster dose using an mRNA COVID-19 vaccine.
What are underlying medical conditions?

People of any age with the conditions listed below are more likely to get severely ill from COVID-19. Severe illness means that a person with COVID-19 may:

  • Be hospitalized
  • Need intensive care
  • Require a ventilator to help them breathe
  • Die

COVID-19 vaccines (initial doses and boosters) and other preventive measures for COVID-19 are important, especially if you are older or have multiple or severe health conditions including those on this list. This list does not include all possible conditions that place you at higher risk of severe illness from COVID-19. If you have a condition not included here, talk to your health care provider about how best to manage your condition and protect yourself from COVID-19.

  • Cancer
  • Chronic kidney disease
  • Chronic liver disease
  • Chronic lung diseases
  • Dementia or other neurological conditions
  • Diabetes (type 1 or 2)
  • Down syndrome
  • Heart conditions
  • HIV infection
  • Immunocompromised state (weakened immune system)
  • Mental health conditions
  • Overweight and obesity
  • Pregnancy
  • Sickle cell disease or thalassemia
  • Smoking, current or former
  • Solid organ or blood stem cell transplant
  • Stroke or cerebrovascular disease, which affects blood flow to the brain 
  • Substance use disorders
  • Tuberculosis
How many doses of a Pfizer-BioNTech or Moderna (mRNA) vaccine are needed for people who are moderately or severely immunocompromised, and whose initial COVID-19 vaccine series was an mRNA vaccine?
  • For the Pfizer-BioNTech COVID-19 vaccine, the second dose for people who are moderately or severely immunocompromised is given 21 days (3 weeks) after the first dose, the third dose is given at least 28 days (4 weeks) after the second dose, and the fourth dose (booster dose) is now recommended to be given at least 3 months after the third dose.
  • For the Moderna COVID-19 vaccine, the second dose for people who are moderately or severely immunocompromised is given 28 days after the first dose, the third dose is given at least 28 days after the second dose, and the fourth dose (booster dose) is now recommended to be given at least 3 months after the third dose.
  • A second booster dose of the Pfizer-BioNTech COVID-19 vaccine should be administered to individuals 12 years of age and older with certain kinds of immunocompromise at least 4 months after receipt of a first booster dose of any authorized or approved COVID-19 vaccine. Likewise, A second booster dose of the Moderna COVID-19 vaccine should be administered at least 4 months after the first booster dose to individuals 18 years of age. These are people who have undergone solid organ transplantation, or who are living with conditions that are considered to have an equivalent level of immunocompromise.
How many vaccine doses are recommended for people who are moderately or severely immunocompromised who received the J&J/Janssen vaccine as their initial COVID-19 vaccine?

The additional (second) dose is given at least 28 days (4 weeks) after the J&J/Janssen dose. The booster dose (third) dose) is given at least 2 months after the additional mRNA dose.

The additional dose must be an mRNA COVID-19 vaccine, and an mRNA COVID-19 vaccine is preferred for the booster dose due to concerns about an increased risk for thrombosis with thrombocytopenia syndrome (TTS) when using the J&J/Janssen vaccine. TTS is a rare but serious adverse event that causes blood clots or issues with clotting. 

Adults who received a primary vaccine and booster dose of Johnson & Johnson’s Janssen COVID-19 vaccine at least 4 months ago should receive a second booster dose using an mRNA COVID-19 vaccine.

What is the rationale for reducing the booster interval—from 5 months to 3 months—for people who are moderately or severely immunocompromised?

People who are moderately or severely immunocompromised may not develop protective immunity after a primary series, even when the recommended mRNA vaccine primary series is used. They are also more likely to lose protective immunity over time and might need to get a booster dose sooner. Early data from several small studies show that people who are moderately or severely immunocompromised often develop increased antibody levels again after a booster dose given at an interval shorter than 5 months. There was no evidence of an increased safety concern. Currently, there is rapid spread of COVID-19 in the United States, and exposures to infected people are hard to avoid. Therefore, providing a booster dose as soon as possible makes sense for those at highest risk for severe complications.

Will people who are moderately or severely immunocompromised need a doctor’s note/prescription or other documentation to receive these doses?

No, individuals can self-identify and receive all doses anywhere vaccines are offered. This will help ensure there are not additional barriers to access for this population. If immunocompromised individuals have questions about their specific medical condition, they may discuss whether getting an additional dose is appropriate for them with their health care provider.