COVID-19 Booster Shots & Additional Dose

CDC Guidelines as of March 30, 2022

  • COVID-19 primary series vaccination is recommended for everyone ages 5 years and older in the United States for the prevention of COVID-19.
  • In most situations, Pfizer-BioNTech or Moderna COVID-19 Vaccines are preferred over the Janssen COVID-19 Vaccine for primary and booster vaccination.
  • A booster dose of COVID-19 vaccine is recommended for everyone ages 12 years and older. Timing of a booster dose varies based on COVID-19 vaccine product and immunocompetence. An 8-week interval may be optimal for people who are not immunocompromised and ages 12-64 years, especially for males ages 12–39 years.
  • Certain immunocompromised individuals ages 12 and older also are eligible for a second Pfizer or Moderna booster shot at least four months after their first booster dose.
  • Added guidance that adults ages 50 years and older who are not moderately or severely immunocompromised may choose to receive a second booster dose using an mRNA COVID-19 vaccine at least 4 months after the first booster dose
  • Added guidance that people ages 18–49 years who are not moderately or severely immunocompromised and who received Janssen COVID-19 Vaccine as both their primary series dose and booster dose may receive a second booster dose using an mRNA COVID-19 vaccine at least 4 months after the first Janssen booster dose.

In general, the same mRNA vaccine product (i.e., the same manufacturer) should be used for all doses in the primary series.

Any product can be used for a booster dose (i.e., heterologous booster dose)  for those ages 18 years and older. Only Pfizer-BioNTech COVID-19 Vaccine can be used for people ages 12-17 years old.  The Moderna COVID-19 single booster dose is half of the dose that is administered for a primary series dose. People who develop myocarditis or pericarditis after mRNA COVID-19 vaccination “should not” get a subsequent dose of any COVID-19 vaccine — though adult men choosing to do so may consider the Johnson & Johnson vaccine.

As for vaccination after COVID-19 treatment or post-exposure prophylaxis, it is no longer necessary to delay vaccine doses for people getting monoclonal antibodies or convalescent plasma

One should get a booster if you are:

  • Ages 12 years and older and received both doses or 3 doses (if immunocompromised) of Pfizer-BioNTech at least 5 months ago.
  • Ages 18 years and older and received both doses or 3 doses (if immunocompromised) of Moderna COVID-19 vaccine at least 5 months ago.
  • Ages 18 years and older and had the Janssen/Johnson & Johnson vaccine at least 2 months ago.

COVID-19 vaccination schedule for the primary series in the general population

All people ages 12 years and older should receive 1 booster dose of a COVID-19 vaccine. Some adults may receive a second booster dose:

  • Adults ages 18-49 years: Those who received Janssen COVID-19 Vaccine as both their primary series dose and booster dose may receive an mRNA COVID-19 booster dose at least 4 months after the Janssen booster dose.
  • Adults ages 50 years and older: A second mRNA booster dose could benefit people ages 50 years and older, as they are at increased risk for severe COVID-19. People ages 50 years and older may choose to receive a second booster dose, if it has been at least 4 months after the first booster

An 8-week interval may be optimal for some people ages 12 years and older, especially for males ages 12 to 39 years. A shorter interval (3 weeks for Pfizer-BioNTech; 4 weeks for Moderna) between the first and second doses remains the recommended interval for people who are moderately to severely immunocompromised; adults ages 65 years and older; and in situations in which there is increased concern about COVID-19 community levels or an individual’s higher risk of severe disease.

Difference between an additional dose and a booster shot

  • An additional dose is for people who may not have had a strong enough immune response from the first two doses.
  • A booster shot is for people whose immune response may have weakened over time.

Who can get an additional vaccine dose?

Immunocompromised individuals include the following:

  • Recent or current treatment of a solid tumor or hematologic malignancy
  • Solid-organ, chimeric antigen receptor (CAR-T), or stem cell transplant within the last two years
  • Moderate to severe primary immunodeficiency (PID)
  • Advanced or untreated HIV
  • Active treatment with high-dose corticosteroids (i.e., ≥20 mg prednisone or equivalent per day), alkylating agents, antimetabolites, transplant-related immunosuppressive drugs, cancer chemotherapeutic agents classified as severely immunosuppressive, tumor necrosis factor (TNF) blockers, and other biologic agents that are immunosuppressive or immunomodulatory
  • Based on clinician assessment of need, chronic medical conditions associated with immunosuppression (e.g., asplenia, chronic renal disease)

Antibody testing and T cell testing are not recommended to evaluate the need for an additional dose of the vaccine because the utility of such testing is not known.

Immunocompromised people who receive Johnson & Johnson’s COVID-19 vaccine are advised to receive an mRNA vaccine dose at least 4 weeks later and a booster dose at least 2 months after that, for a total of three doses (mRNA preferred for the booster as well).

COVID-19 vaccination schedule for people with moderate or severe immunocompromised

*People ages 12 years and older may choose to receive a second booster dose using an mRNA COVID-19 vaccine if it has been at least 4 months after the first booster dose.

Find a COVID-19 Vaccine: Click for information on how to get a COVID-19 vaccine.  For King County residents, click for a list of pop-up clinics.  Click for additional resources to get a booster in Western WA.