Additional vaccine dose - protection against COVID-19

For some people with a weakened immune system, an additional dose of the COVID-19 vaccine is now available to help boost their protection against COVID-19.;

Having a weakened immune system puts you at higher risk of severe illness from COVID-19 and makes you much more likely to have a breakthrough infection. Studies show that the initial vaccine doses are less effective for people with weakened immune systems, as they don’t always produce enough antibodies to build adequate levels of protection, and that hospitalized breakthrough infections are rare but are also more likely in immunocompromised people. An additional dose of the vaccine will help to further strengthen your immunity against COVID-19.

Additional vaccine dose eligibility

An additional dose of the COVID-19 vaccine has been authorized by the Food and Drug Administration (FDA) for those who are moderately to severely immunocompromised. This includes people who have:

  • Been 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 two years or are taking medicine to suppress the immune system
  • Moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
  • Advanced or untreated HIV infection
  • Active treatment with high-dose corticosteroids or other drugs that may suppress your immune response

If you are unsure if you are eligible for an additional dose of the COVID-19 vaccine at this time or have concerns about the effectiveness of the vaccine you received, please contact your primary care provider.

How to schedule your additional dose appointment

We are offering additional dose Pfizer-BioNTech (Comirnaty) vaccination appointments through self-scheduling or via MyChart.

As a reminder, first and second dose COVID-19 vaccines are currently available to all individuals ages 12 and older. Get more information on the COVID-19 vaccines or schedule a vaccination appointment.

Frequently asked questions about the additional dose

Who is considered immunocompromised and eligible for an additional dose of the COVID-19 vaccine at this time?

People considered moderately to severely immunocompromised are limited to include those who have:

  • Been 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
  • Moderate or severe primary immunodeficiency (such as DiGeorge syndrome, Wiskott-Aldrich syndrome)
  • Advanced or untreated HIV infection
  • Active treatment with high-dose corticosteroids or other drugs that may suppress your immune response

Those who fall into these categories make up only about 3% of the adult population. Although those with breakthrough COVID-19 infections have been rarely hospitalized, fully vaccinated, immunocompromised people have accounted for a large proportion of those who do end up hospitalized with breakthrough infections. If you are uncertain if you are eligible to receive an additional COVID-19 vaccine dose based on these criteria, please contact your primary care provider.

What if I don’t know if I’m considered immunocompromised, but have health complications that put me more at risk?

If you are unsure if you are eligible for an additional dose of the COVID-19 vaccine at this time or have concerns about the effectiveness of the vaccine you received, please contact your primary care provider.

If I’ve already had a COVID-19 vaccine but am considered immunocompromised, why do I need an additional dose?

Having a weakened immune system puts you at higher risk of severe illness from COVID-19 and makes you much more likely to have a breakthrough infection (breakthrough infections occur when vaccinated individuals contract the disease they’ve been vaccinated against).

Studies show that the initial vaccine doses are not as effective for people with weakened immune systems, as they don’t always produce the same level of antibodies to build adequate levels of protection. Hospitalized breakthrough cases are rare, but are also more likely in immunocompromised people. An additional dose of the vaccine will help to further strengthen your immunity against COVID-19.

If I’ve already had two doses of a COVID-19 vaccine or one dose of the Johnson & Johnson vaccine, am I considered fully vaccinated?

If you are moderately to severely immunocompromised and have received two doses of the Pfizer-BioNTech (Comirnaty) or Moderna vaccines, you are no longer considered fully vaccinated and are now recommended to receive the additional dose in the vaccine series.

If you have received the one-dose Johnson & Johnson (Janssen) vaccine, data is not available at this time to support that you need to get another dose.

How do I get an additional dose of the COVID-19 vaccine?

Get more information on receiving an additional dose of the Pfizer-BioNTech Vaccine (Comirnaty) from UI Health Care. Many local pharmacies are also offering the additional dose of the COVID-19 vaccines needed for immunocompromised people. At this time, we are offering only additional dose vaccinations for the Pfizer-BioNTech Vaccine (Comirnaty).

If you received Moderna for your first two doses, you should also receive Moderna for your additional dose.

UI Health Care is not yet administering additional doses of the Moderna vaccine, though we have plans to offer this soon. Additional information will be shared when this service is available through UI Health Care.

Many local pharmacies are also offering both the Pfizer-BioNTech (Comirnaty) and Moderna vaccines for this additional dose of the COVID-19 vaccines for immunocompromised people.

Do I need to get the same COVID-19 vaccine I got for my first two doses? And what do I do if I got the Johnson & Johnson vaccine?

The CDC recommends you get the same vaccine you got for your first two doses. So, if you got the Pfizer-BioNTech (Comirnaty) or Moderna as your first two doses, you should receive that same brand for your additional dose.

An additional dose of the Johnson & Johnson (Janssen) vaccine is not recommended at this time.

UI Health Care is not yet administering additional doses of the Moderna vaccine, though we have plans to offer this soon. Additional information will be shared when this service is available through UI Health Care.

If I’m eligible and get an additional dose of the COVID-19 vaccine, will I have enough protection?

The strongest protection comes from getting vaccinated.

Although the additional dose of the COVID-19 vaccine will further strengthen your immunity, it is important to realize that the vaccines are not 100% effective at preventing illness or from contracting (and then spreading) COVID-19. You should also protect yourself and others by wearing a mask, social distancing, avoiding crowds, and washing your hands often. Each of these are important ways to reduce your risk of getting COVID-19, but they become very effective when you combine them.

If you are moderately to severely immunocompromised and do not get an additional dose of the Pfizer-BioNTech (Comirnaty) or Moderna vaccines, you will no longer be considered fully vaccinated.

Should I get my additional dose of the COVID-19 vaccine if I’m not feeling well?

No. People who are experiencing symptoms associated with COVID-19 should wait to be vaccinated until they have recovered from their illness and have met the criteria for discontinuing isolation if they are found to test positive.

Regardless of your vaccination status or whether or not you are immunocompromised, it is important to get tested if you are experiencing any symptoms of COVID-19 and to stay home if you are sick.

What to do if you feel unwell 

To be safe, you should stay home if you feel unwell. You should also schedule a video visit if you experience any symptoms that are similar to symptoms of COVID-19.

COVID-19 symptoms:

  • A fever in the last 24 hours
  • New or worsening:
    • Sore throat
    • Cough
    • Shortness of breath

I’m not moderately to severely immunocompromised, but I would like to get an additional dose anyway.

Although President Biden’s administration has recently announced that all individuals will be eligible to receive a COVID-19 booster vaccine 8 months after their second dose, the U.S. Food and Drug Administration (FDA) and the Centers for Disease Control and Prevention must first authorize booster vaccines. At this time, the FDA and the CDC have not yet authorized additional doses or boosters for the COVID-19 vaccines outside of those who are moderately to severely immunocompromised.

Last reviewed: 
August 2021

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