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Third Dose of COVID-19 Vaccine Now Authorized

August 19, 2021

On August 13, 2021 the Centers for Disease Control and Prevention (CDC) provided new recommendations for the mRNA (Pfizer and Moderna) COVID-19 vaccines for moderately to severely immunocompromised people. The CDC now recommends a third dose of the Pfizer or Moderna COVID-19 vaccine for these individuals.

These are people who:

  • Are actively being treated for cancer
  • Have received a solid organ transplant and are taking medicine to suppress the immune system
  • Have received CAR-T cell therapy
  • Have received a stem cell transplant within the last 2 years or are taking medicine to suppress the immune system after a stem cell transplant
  • Have moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
  • Have advanced or untreated HIV infection
  • Are taking high-dose corticosteroids (i.e., the equivalent of 20 or more milligrams of Prednisone a day) or are taking other drugs that may suppress the immune response

Why was an additional third dose recommended?

People who are moderately to severely immunocompromised are more likely to become very sick if they get COVID-19. They may also have a longer illness and may not get the same protection from two doses of the Pfizer and Moderna COVID-19 vaccines as other people do. The available data suggests that they may receive more protection from a third dose of vaccine.

What is the difference between an additional dose + a booster dose?

  • Additional dose after a primary series: An additional dose of vaccine is administered when the immune response following a primary vaccine series is likely to be insufficient. For example, in immunocompromised patients.
  • Booster dose: Initial immune response to a primary vaccine series is thought to be sufficient, however, an additional dose of vaccine is administered when the initial immune response to a primary series is likely to have waned over time. While booster doses are not recommended at this time, as you may have heard in the news, we do expect guidance regarding booster doses to be released soon. Data on this is monitored closely and any changes in recommendations will be updated as more information becomes available.

For those receiving the third dose, does it have to be the same vaccine as the first two doses?

Yes, the third dose should be the same vaccine as the first two. Those who got Pfizer for their first two doses, should get Pfizer for their third and the same with Moderna. At present, there are no recommendations for an additional dose of the Johnson & Johnson (Janssen) vaccine.

Where can I get the COVID-19 Vaccine?

Our health system has several vaccine clinics that accept appointments and walk-ins. You can also visit your local pharmacy.

Do I need a note from my doctor?

You do not need a doctor's note to receive a third dose, but you will need to attest to being immunocompromised.

Do I need to bring documentation to my prior doses?

You should try your best to bring documentation of your prior doses, particularly if they were not given at the location you are getting the third dose.

When should moderately to severely immunocompromised people get a third dose of vaccine?

The CDC recommends that the third dose be administered at least 28 days after receiving the second dose of the mRNA vaccine. But you might want to consult first with the doctor that prescribes your immunocompromising medication to best assess the timing for this third dose.

Are there side effects to the third dose?

To date, the side effects reported after the third dose of the Pfizer or Moderna vaccine were similar to what people experienced after receiving doses 1 and 2. Pain at injection site was the most commonly reported side effect. Most symptoms were mild to moderate and resolved within 3 days.

Get the Latest Information on COVID-19 Vaccine Booster Doses + Third Doses
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What You Need To Know about COVID-19 Third Doses + Boosters
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