Booster and Third Dose

Updated 10/25/2021

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COVID-19 Vaccine Booster Dose

Pfizer Vaccine Booster Shots

On September 24, the Centers for Disease Control and Prevention (CDC) and the Oregon Health Authority (OHA) recommended a booster dose of the Pfizer COVID-19 vaccine six months after the second dose for anyone:

  • 65 years of age and older
  • 18 years and older at high risk of severe COVID-19 (Underlying medical conditions)
  • 18 years and older with frequent institutional or occupational exposure to COVID-19
    • This includes individuals living in long term care settings

Moderna Vaccine Booster Shots

On October 22 the CDC  and the OHA announced new guidelines, recommending a booster shot of the Moderna COVID-19 vaccine at least six months after their second dose for anyone:

  • 65 years of age and older
  • 18 years and older at high risk of severe COVID-19 (Underlying medical conditions)
  • 18 years and older with frequent institutional or occupational exposure to COVID-19
    • This includes individuals in long term care settings

The Moderna booster is only half the dosage of the primary Moderna series. 

Johnson & Johnson Vaccine Booster Shots

On October 22 the CDC and the OHA announced new guidelines, recommending a booster shot of the Johnson & Johnson COVID-19 vaccine at least two months after the initial dose for the following individuals:

  • Anyone 18 years or older who received the Johnson & Johnson vaccine

Mixing brands of COVID-19 vaccine

On October 21, the CDC also released new guidance on mixing vaccine brands, approving the use of a brand of COVID-19 vaccine different from a person’s primary vaccination as a booster shot. Recipients of the booster shot must qualify for a booster based on the recommendations for the brand they received as their primary vaccination. Mixing COVID-19 brands for your primary vaccination is not approved at this time.

For instance, if you received a Johnson & Johnson shot, you would be eligible to receive a booster shot two months after you received your first dose. This booster could be one of any of the three brands.

If instead, you received the Pfizer vaccine as your primary vaccination, you could not receive a booster shot until at least six months after your second dose of Pfizer, and you would need to be in an eligible group: 65 years old and older, or 18 years old and older with a higher risk of contracting COVID-19. If you met all of those conditions, you could then receive a booster of any of the three available brands.


 

Third Dose for Immunocompromised Individuals

A third dose of Pfizer/Comirnaty or Moderna vaccine is now recommended for individuals who have moderately to severely compromised immune systems. Individuals should talk to their healthcare provider about their medical condition and whether getting an additional dose is appropriate for them. Learn more about this recommendation here. You should only receive three doses: Even if you qualify for both the third dose and the booster, you should not receive any more than three doses.

For more information about the difference between a booster shot and a third dose, please see this FAQ from the OHA.