COVID-19 Vaccine Booster Doses and Third Doses


This page has been automatically translated from English. MSDH has not reviewed this translation and is not responsible for any inaccuracies.

Additional COVID-19 vaccine doses can improve protection against COVID-19 for older adults, those with certain medical conditions, and other groups at higher risk.

Booster Vaccinations

Adults 18 and over and children 12-17 years old may be eligible for COVID-19 vaccine booster doses.

Boosters are especially recommended for those who are 65 or older, or with ongoing medical problems.

Pfizer and Moderna

  • If you are at least 18, and your second dose of Pfizer or Moderna vaccine was at least five months ago, you are eligible for a booster dose of either Pfizer or Moderna vaccine.
  • If you are 12-17 years old and your second dose of Pfizer vaccine was at least five months ago, you are eligible for a booster dose of Pfizer vaccine.

Johnson & Johnson

If you were vaccinated with Johnson & Johnson (Janssen) vaccine at least two months ago and you are 18 or older, you are eligible for a booster.

Getting a Booster Dose

  • Booster vaccinations are free of charge.
  • Check with your doctor, a pharmacy, or other vaccination provider about getting a COVID-19 booster dose. Find a vaccination provider »
  • Booster doses are also available at county health departments. Use the online scheduler below, or call the Mississippi COVID-19 Hotline at 877-978-6453 for assistance.

Schedule a booster dose

Third Vaccine Doses

A third dose of COVID-19 vaccine can provide added protection if you have a medical condition that affects your immune system and you are at high risk for developing more serious illness from COVID-19.

Third vaccine doses are available only for those who received Moderna or Pfizer vaccine, and whose last shot was at least 4 weeks ago.

Qualifying Conditions

You qualify for a third dose of Moderna or Pfizer vaccine if you:

  • 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
  • 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 steroids or other drugs that may suppress your immune response
  • Have any other medical condition that your provider says will limit your immune response

Getting a Third Dose

You can schedule an additional vaccination dose at a county health department or through your doctor or regular health care provider.

  • Schedule a third dose appointment at a county health department
    You'll be asked questions about qualifying for additional vaccination and be able to select a county health department for an appointment.

Schedule a third dose appointment

  • Consult your doctor or a health care provider. They can evaluate your health status and determine whether you need an additional vaccination dose. If you do, they will provide the vaccination.
Last reviewed on Sep 29, 2021
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