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COVID- 19 Third Dose Approved for Certain Immunocompromised Individuals

August 18, 2021

The Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) recently approved an additional third dose of the COVID-19 vaccine for certain people who are immunocompromised due to a medical condition or because they are receiving medications or treatments that weaken their immune response. 
The specific conditions and treatments include but are not limited to:
  • 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 in the last 2 years or are taking medicine to suppress the immune system
  • Moderate or severe primary immunodeficiency (such as common variable immunodeficiency, DiGeorge syndrome, Wiskott-Aldrich syndrome)
  • Active treatment with high-dose corticosteroids or other drugs that may suppress your immune response (for example: azathioprine, cyclophosphamide, cyclosporine, interferon, methotrexate, mycophenolate, biologic medicines/monoclonal antibodies like infliximab, adalimumab, etanercept)
  • Advanced or untreated HIV infection
People who are immunocompromised are especially vulnerable to COVID-19 because they are more at risk of serious, prolonged illness, and may benefit from an additional dose to make sure they have enough protection against COVID-19. The CDC recommendation applies to immunocompromised people who received one of the mRNA vaccines (Pfizer or Moderna) and not the one-shot Johnson & Johnson vaccine (J&J).
Cambridge residents who have questions about whether a third dose of vaccine is recommended should contact their medical provider to discuss these recommendations.
Additional information on third dose vaccines may be found on the CDC’s website.

Suzy Feinberg, MPH
Public Information Officer

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