The Centers for Disease Control (CDC) has approved additional doses of the COVID-19 vaccine for certain people who have already been fully vaccinated.

The mobile clinics sponsored by UM Baltimore Washington Medical Center are offering additional doses of the COVID vaccine — either a third dose for immunocompromised people or a booster shot for eligible people.

If you are getting a booster or third dose at our mobile clinic, you must bring your COVID-19 vaccine card. Learn how to get a COVID vaccine card replacement.

Eligibility for Additional Doses

Eligibility for these additional doses varies, depending on:

  • The type of vaccine initially received
  • When it was received
  • In some cases, specific risk factors related to age, health, employment and living circumstances

Regardless of the vaccine you initially received, if you are eligible for a booster, you may receive any of the three vaccines available in the United States (Pfizer, Moderna or Johnson & Johnson).

However, the third dose for immunocompromised people should be the same as the initial vaccine.

Note: Not all vaccine types may be available at each clinic.

To schedule a different vaccine, please see these resources for scheduling a COVID vaccine at other locations in Maryland.

Who Can Receive a Booster

If You Initially Received Pfizer or Moderna

The CDC says people are eligible for a single booster shot at least six months after the second dose of their initial vaccination if they are:

  • 65 years of age and older
  • Age 18 and older who live in long-term care settings
  • Age 18 and older who have underlying medical conditions
  • Age 18 and older who live or work in high-risk settings

If You Initially Received J&J

The CDC says individuals ages 18 and older who received the J&J vaccine should get a single booster shot at least two months after their initial vaccination.

For additional details on who may get a booster, visit the CDC’s website.


Third Dose for Immunocompromised People

The CDC recommends that people who are moderately to severely immunocompromised receive a third dose of an mRNA COVID-19 vaccine at least 28 days after the second dose of either the Pfizer or Moderna vaccine.

Unlike with a booster, you should receive the same vaccine as your initial vaccination.

This additional dose of Pfizer or Moderna is only for people who are immunocompromised as outlined in the CDC's recommendations. 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 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.

Please talk to your doctor about whether this third dose is appropriate for you.

This third dose is not the same as a booster shot. If you are immunocompromised and receive a third dose, there is no recommendation at this time for you to also receive a booster dose of the COVID-19 vaccine.

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