Interim Clinical Considerations for Use of COVID-19 Vaccines in the United States

FDA authorized Novavax COVID-19 Vaccine, Adjuvanted (2024 – 2025 Formula) under Emergency Use Authorization on August 30, 2024. This page will be updated soon with additional information.

Recommendations for 2024–2025 Moderna COVID-19 Vaccine and 2024–2025 Pfizer-BioNTech COVID-19 Vaccine

People who are not moderately or severely immunocompromised

Initial vaccination

• Ages 6 months–4 years
  • 2 doses of 2024–­2025 Moderna or 3 doses of 2024–­2025 Pfizer-BioNTech
  • 1 dose of 2024–2025 Moderna or 1 dose of 2024–2025 Pfizer-BioNTech

  Received previous doses of a COVID-19 vaccine

  • Ages 6 months–4 years
    • 1 or 2 doses of 2024–­2025 mRNA vaccine from the same manufacturer as administered for initial vaccination, depending on the vaccine and the number of prior doses
    • 1 dose of 2024–­2025 Moderna or 1 dose of 2024–­2025 Pfizer-BioNTech

    Additional dose: An additional dose of 2024–­2025 COVID-19 vaccine for people ages 65 years and older who are not moderately or severely immunocompromised is NOT currently recommended.

    People who are moderately or severely immunocompromised

    Initial vaccination

    • Ages 6 months and older
      • 3 doses of 2024–­2025 Moderna or 3 doses of 2024–­2025 Pfizer-BioNTech

      Received previous doses of a COVID-19 vaccine

      • Recommended mRNA vaccine and number of 2024–­2025 doses are based on age and vaccination history

      Additional doses: People who are moderately or severely immunocompromised ages 6 months and older may receive 1 or more age-appropriate doses of a 2024–2025 mRNA COVID-19 vaccine.

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      Overview of COVID-19 vaccination

      These clinical considerations provide information to healthcare professionals and public health officials on use of COVID-19 vaccines. They are informed by:

      • Recommendations of the Advisory Committee on Immunization Practices (ACIP) and the Centers for Disease Control and Prevention (CDC)
      • COVID-19 vaccine approval (licensure) under a Biologics License Application (BLA) or authorization under an Emergency Use Authorization (EUA) by the U.S. Food and Drug Administration (FDA)
      • CDC’s Emergency Use Instructions (EUI) for FDA-approved vaccines
      • The World Health Organization’s (WHO) Emergency Use Listing (EUL) or Prequalification of COVID-19 vaccines
      • ACIP’s General Best Practice Guidelines for Immunization

      COVID-19 vaccines

      Two types of COVID-19 vaccines are recommended for use in the United States:

      • mRNA vaccines
        • Moderna COVID-19 Vaccine (2024–2025 Formula) is authorized for children ages 6 months–11 years; SPIKEVAX is the licensed Moderna product for people ages 12 years and older. These vaccines are hereafter referred to as 2024–2025 Moderna COVID-19 Vaccine.
        • Pfizer-BioNTech COVID-19 Vaccine (2024–2025 Formula) is authorized for children ages 6 months–11 years; COMIRNATY is the licensed Pfizer-BioNTech product for people ages 12 years and older. These vaccines are hereafter referred to as 2024–2025 Pfizer-BioNTech COVID-19 Vaccine.
        • Protein subunit vaccine
          • Novavax COVID-19 Vaccine, Adjuvanted (2023–2024 Formula) is authorized for people ages 12 years and older. It is hereafter referred to as 2023–2024 Novavax COVID-19 Vaccine. The 2023–2024 Novavax COVID-19 Vaccine is no longer available for use in the United States as all doses have expired.

          There is no preferential recommendation for the use of any one COVID-19 vaccine over another when more than one recommended and age-appropriate vaccine is available.

          2024-2025 mRNA COVID-19 vaccine composition

          The 2024–2025 formulation for Moderna and Pfizer-BioNTech COVID-19 vaccines approved and authorized in the United States has been updated to a monovalent vaccine based on the Omicron JN.1-lineage of SARS-CoV-2, KP.2.

          COVID-19 vaccine-specific package inserts and EUA fact sheets for healthcare providers (fact sheets) and U.S. COVID-19 Vaccine Product Information can be consulted for a full list of ingredients and information on the conditions of use, storage and handling, preparation, and administration procedures.

          Recommendations for the use of COVID-19 vaccines

          Groups recommended for vaccination

          COVID-19 vaccination is recommended for everyone ages 6 months and older in the United States for the prevention of COVID-19. There is currently no FDA-approved or FDA-authorized COVID-19 vaccine for children younger than age 6 months.

          CDC recommends that people receive all recommended COVID-19 vaccine doses. Vaccination is especially important for people at highest risk of severe COVID-19, including people ages 65 years and older; people with underlying medical conditions, including immune compromise; people living in long-term care facilities; and pregnant people to protect themselves and their infants.

          Vaccine dosage and administration

          General Best Practice Guidelines for Immunization apply to COVID-19 vaccination unless otherwise noted. People should receive the age-appropriate vaccine product and dosage based on their age on the day of vaccination and follow the recommended dosing intervals (Table 1 and Table 2).

          COVID-19 vaccine doses should be administered by the intramuscular route.

          Overview of the COVID-19 vaccination schedule

          An overview of the 2024–2025 COVID-19 vaccination schedule for Moderna and Pfizer-BioNTech vaccines is summarized below. Detailed vaccination schedules can be found in Table 1 for people who are not moderately or severely immunocompromised and in Table 2 for people who are moderately or severely immunocompromised. See Appendix A for recommendations for people who received COVID-19 vaccine outside the United States.

          Recommendations for people who are not moderately or severely immunocompromised

          Initial vaccination

          • Ages 6 months–4 years
            • 2 doses of 2024–­2025 Moderna or 3 doses of 2024–­2025 Pfizer-BioNTech
            • 1 dose of 2024–2025 Moderna or 1 dose of 2024–2025 Pfizer-BioNTech

            Received previous doses of a COVID-19 vaccine

            • Ages 6 months–4 years
              • 1 or 2 doses of 2024–­2025 mRNA vaccine from the same manufacturer as administered for initial vaccination, depending on the vaccine and the number of prior doses
              • 1 dose of 2024–­2025 Moderna or 1 dose of 2024–­2025 Pfizer-BioNTech

              Additional dose: An additional dose of 2024–2025 COVID-19 vaccine for people ages 65 years and older who are not moderately or severely immunocompromised is NOT currently recommended. ACIP will monitor available data on the epidemiology of COVID-19 and the safety and effectiveness of COVID-19 vaccines, and update COVID-19 vaccination recommendations as needed, including for people ages 65 years and older.

              Recommendations for people who are moderately or severely immunocompromised

              Initial vaccination

              • Ages 6 months and older
                • 3 doses of 2024–­2025 Moderna or 3 doses of 2024–­2025 Pfizer-BioNTech

                Received previous doses of a COVID-19 vaccine

                • Recommended mRNA vaccine and number of 2024–­2025 doses are based on age and vaccination history

                Additional doses: People who are moderately or severely immunocompromised ages 6 months and older may receive 1 or more age-appropriate additional doses of a 2024–2025 mRNA COVID-19 vaccine.

                COVID-19 vaccination guidance for people who are not moderately or severely immunocompromised

                The COVID-19 vaccination schedule for people who are not moderately or severely immunocompromised is detailed in Table 1 for 2024–2025 mRNA COVID-19 vaccines (Moderna and Pfizer-BioNTech). The recommended vaccine and number of 2024–2025 COVID-19 vaccine doses are based on age and vaccination history.

                Table 1. People who are not moderately or severely immunocompromised: Recommended COVID-19 vaccination schedule by COVID-19 vaccination history, August 23, 2024

                2024–2025 mRNA vaccines

                Ages 6 months–4 years

                • All COVID-19 vaccine doses in this age group should be from the same manufacturer; see Interchangeability of COVID-19 vaccines for information on circumstances in which vaccine from a different manufacturer may be considered.
                Ages 6 months–4 years

                COVID-19 vaccination history	2024–2025 vaccine	Number of 2024–2025 vaccine doses indicated	Dosage (mL/ug)	Interval between doses
                Unvaccinated	Moderna	2	0.25 mL/25 ug	Dose 1: Day 0 Dose 2: 4–8 weeks after Dose 1*
                	OR
                	Pfizer-BioNTech	3	0.3 mL/3 ug	Dose 1: Day 0 Dose 2: 3–8 weeks after Dose 1* Dose 3: At least 8 weeks after Dose 2
                1 dose any Moderna	Moderna	1	0.25 mL/25 ug	Dose 2: 4–8 weeks after Dose 1*
                2 or more doses any Moderna NOT including at least 1 dose 2024–2025 Moderna	Moderna	1	0.25 mL/25 ug	At least 8 weeks after last dose
                2 or more doses any Moderna INCLUDING at least 1 dose 2024–2025 Moderna	No further doses indicated
                1 dose any Pfizer-BioNTech	Pfizer-BioNTech	2	0.3 mL/3 ug	Dose 2: 3–8 weeks after Dose 1* Dose 3: At least 8 weeks after Dose 2
                2 doses any Pfizer-BioNTech	Pfizer-BioNTech	1	0.3 mL/3 ug	Dose 3: At least 8 weeks after Dose 2
                3 or more doses any Pfizer-BioNTech NOT including at least 1 dose 2024–2025 Pfizer-BioNTech	Pfizer-BioNTech	1	0.3 mL/3 ug	At least 8 weeks after last dose
                3 or more doses any Pfizer-BioNTech INCLUDING at least 1 dose 2024–2025 Pfizer-BioNTech	No further doses indicated

                • See footnote † for guidance on children who transition from age 4 years to age 5 years during the initial vaccination series.
                Ages 5–11 years

                COVID-19 vaccination history	2024–2025 vaccine	Number of 2024–2025 doses indicated	Dosage (mL/ug)	Interval between doses
                Unvaccinated	Moderna	1	0.25 mL/25 ug	—
                	OR
                	Pfizer-BioNTech	1	0.3 mL/10 ug	—
                1 or more doses any mRNA NOT including 1 dose any 2024–2025 mRNA vaccine	Moderna	1	0.25 mL/25 ug	At least 8 weeks after last dose
                	OR
                	Pfizer-BioNTech	1	0.3 mL/10 ug	At least 8 weeks after last dose
                1 or more doses any mRNA, INCLUDING 1 dose 2024–2025 mRNA vaccine	No further doses indicated

                Ages 12 years and older

                • People ages 65 years and older: An additional dose of 2024–2025 COVID-19 vaccine is not currently recommended.
                Ages 12 years and older

                COVID-19 vaccination history	2024–2025 vaccine	Number of 2024–2025 doses indicated	Dosage (mL/ug)	Interval between doses
                Unvaccinated	Moderna	1	0.5 mL/50 ug	—
                	OR
                	Pfizer-BioNTech	1	0.3 mL/30 ug	—
                1 or more doses any mRNA, NOT including 1 dose any 2024–2025 mRNA vaccine	Moderna	1	0.5 mL/50 ug	At least 8 weeks after last dose
                	OR
                	Pfizer-BioNTech	1	0.3 mL/30 ug	At least 8 weeks after last dose
                1 or more doses any mRNA, INCLUDING 1 dose any 2024–2025 mRNA vaccine	No further doses indicated
                1 or more doses any Novavax, NOT including 1 dose any 2024–2025 mRNA vaccine	Moderna	1	0.5 mL/50 ug	At least 8 weeks after last dose
                	OR
                	Pfizer-BioNTech	1	0.3 mL/30 ug	At least 8 weeks after last dose

                * An 8-week interval between the first and second COVID-19 vaccine (Moderna and Pfizer-BioNTech) doses might be optimal for some people as it might reduce the rare risk of myocarditis and pericarditis associated with these vaccines.

                † Children who transition from age 4 years to age 5 years during the initial vaccination series should receive 1 dose of vaccine from the same manufacturer at the dosage for children ages 5–11 years on or after turning age 5 years:

                • Moderna: 1 dose of 2024–2025 Moderna (0.25 mL/25 ug) 4-8 weeks after the first dose; there is no dosage change.
                • Pfizer-BioNTech: 1 dose of 2024–2025 Pfizer-BioNTech (0.3 mL/10 ug). If the 10 ug dose is the second dose, administer 3–8 weeks after the first dose; if it is the third dose, administer at least 8 weeks after the second dose.

                Considerations for extended intervals for COVID-19 vaccine doses

                An 8-week interval between the first and second mRNA COVID-19 vaccine (Moderna, Pfizer-BioNTech) doses might be optimal for some people as it might reduce the rare risk of myocarditis and pericarditis associated with these COVID-19 vaccines.

                While absolute risk remains small, an elevated risk for myocarditis and pericarditis has been observed among mRNA COVID-19 vaccine recipients, particularly in males ages 12–39 years (see COVID-19 vaccination and myocarditis and pericarditis for additional information). Cases of myocarditis and pericarditis were identified in clinical trials of Novavax COVID-19 Vaccine and through passive surveillance during post-authorization use outside the United States.

                Under the current COVID-19 vaccination schedule (Table 1), the extended interval consideration applies only to the following people who are not moderately or severely immunocompromised:

                • Ages 6 months–4 years, depending on their vaccination history

                The minimum interval between the first and second doses continues to be recommended for:

                • People who are moderately or severely immunocompromised
                • Situations when the fullest possible protection needs to be achieved sooner (e.g., increased concern about an individual’s higher risk for severe disease)

                COVID-19 vaccination guidance for people who are moderately or severely immunocompromised including additional doses

                The COVID-19 vaccination schedule for people ages 6 months and older who are moderately or severely immunocompromised is detailed in Table 2 for 2024–2025 mRNA COVID-19 vaccines. The recommended vaccine and number of 2024–2025 COVID-19 vaccine doses are based on age and vaccination history. In all age groups, COVID-19 vaccine doses from the same manufacturer should be administered whenever recommended; see Interchangeability of COVID-19 vaccines for circumstances in which doses from different manufacturers may be considered.

                Additional doses: People who are moderately or severely immunocompromised may receive additional dose(s) of 2024–2025 mRNA COVID-19 vaccine after the last 2024–2025 mRNA COVID-19 vaccine dose indicated in Table 2. For detailed guidance on administration of age-appropriate additional doses, consult Table 2.

                For information on the use of pemivibart (Pemgarda™) for COVID-19 pre-exposure prophylaxis, see COVID-19 vaccination and pemivibart.

                Table 2. People who are moderately or severely immunocompromised: Recommended COVID-19 vaccination schedule by COVID-19 vaccination history, August 23, 2024

                2024–2025 mRNA vaccines

                Ages 6 months–4 years

                Ages 6 months–4 years

                COVID-19 vaccination history	2024–2025 vaccine	Number of 2024–2035 doses indicated	Dosage (mL/ug)	Interval between doses
                Unvaccinated	Moderna	3	0.25 mL/25 ug	Dose 1: Day 0 Dose 2: 4 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                	OR
                	Pfizer-BioNTech	3	0.3 mL/3 ug	Dose 1: Day 0 Dose 2: 3 weeks after Dose 1 Dose 3: At least 8 weeks after Dose 2 See additional doses
                1 dose any Moderna	Moderna	2	0.25 mL/25 ug	Dose 2: 4 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                2 doses any Moderna	Moderna	1	0.25 mL/25 ug	Dose 3: At least 4 weeks after Dose 2 See additional doses
                3 or more doses any Moderna NOT including at least 1 dose 2024–2025 Moderna	Moderna	1	0.25 mL/25 ug	At least 8 weeks after last dose See additional doses
                3 or more doses any Moderna INCLUDING at least 1 dose 2024–2025 Moderna	See additional doses
                1 dose any Pfizer-BioNTech	Pfizer-BioNTech	2	0.3 mL/3 ug	Dose 2: 3 weeks after Dose 1 Dose 3: At least 8 weeks after Dose 2 See additional doses
                2 doses any Pfizer-BioNTech	Pfizer-BioNTech	1	0.3 mL/3 ug	Dose 3: At least 8 weeks after Dose 2 See additional doses
                3 or more doses any Pfizer-BioNTech NOT including at least 1 dose 2024–2025 Pfizer-BioNTech	Pfizer-BioNTech	1	0.3 mL/3 ug	At least 8 weeks after last dose See additional doses
                3 or more doses any Pfizer-BioNTech INCLUDING at least 1 dose 2024–2025 Pfizer-BioNTech	See additional doses
                ADDITIONAL DOSES: Children in this age group may receive 1 additional dose of 2024–2025 mRNA COVID-19 vaccine from the same manufacturer as the initial series at least 2 months after the last 2024–2025 mRNA vaccine dose indicated in the table. Further additional 2024–2025 mRNA dose(s) may be administered from the same manufacturer, informed by the clinical judgment of a healthcare provider and personal preference and circumstances. Any further additional doses should be administered at least 2 months after the last 2024–2025 mRNA vaccine dose.

                • See footnote* for guidance on children who transition from age 4 years to age 5 years during the initial vaccination series.
                Age 5-11 years

                COVID-19 vaccination history	2024-2025 vaccine	Number of 2024-2025 doses indicated	Dosage (mL/ug)	Interval between doses
                Unvaccinated	Moderna	3	0.25 mL/25 ug	Dose 1: Day 0 Dose 2: 4 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                	OR
                	Pfizer-BioNTech	3	0.3 mL/10 ug	Dose 1: Day 0 Dose 2: 3 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                1 dose any Moderna	Moderna	2	0.25 mL/25 ug	Dose 2: 4 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                2 doses any Moderna	Moderna	1	0.25 mL/25 ug	Dose 3: At least 4 weeks after Dose 2 See additional doses
                1 dose any Pfizer-BioNTech	Pfizer-BioNTech	2	0.3 mL/10 ug	Dose 2: 3 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                2 doses any Pfizer-BioNTech	Pfizer-BioNTech	1	0.3 mL/10 ug	Dose 3: At least 4 weeks after Dose 2 See additional doses
                3 or more doses any Moderna or 3 or more doses any Pfizer-BioNTech NOT including at least 1 dose any 2024–2025 mRNA vaccine†	Moderna	1	0.25 mL/25 ug	At least 8 weeks after last dose See additional doses
                	OR
                	Pfizer-BioNTech	1	0.3 mL/10 ug	At least 8 weeks after last dose See additional doses
                3 or more doses any mRNA vaccine INCLUDING at least 1 dose any 2024–2025 mRNA vaccine	See additional doses
                ADDITIONAL DOSES: Children in this age group may receive 1 additional dose of 2024–2025 mRNA COVID-19 vaccine (either Moderna or Pfizer-BioNTech, regardless of the manufacturer for the initial series) at least 2 months after the last 2024–2025 mRNA vaccine dose indicated in the table. Further additional mRNA dose(s) may be administered, informed by the clinical judgment of a healthcare provider and personal preference and circumstances. Any further additional doses should be administered at least 2 months after the last 2024–2025 mRNA vaccine dose.

                *Children who transition from age 4 years to age 5 years during the initial vaccination series should complete the 3-dose series using the dosage for children ages 5–11 years for all doses received on or after turning age 5 years:

                • Moderna series: 2024–2025 Moderna, 0.25 mL/25 ug; there is no dosage change
                • Pfizer-BioNTech series: 2024–2025 Pfizer-BioNTech, 0.3 mL/10 ug

                † This COVID-19 vaccine history refers to previous receipt of 3 doses of mRNA vaccine from the same manufacturer (i.e., Moderna or Pfizer-BioNTech) for initial vaccination followed by 1 or more additional doses of either Moderna or Pfizer-BioNTech, excluding receipt of 2024–2025 mRNA vaccine for any previous doses.

                Ages 12 years and older

                • See footnote* for guidance on children who transition from age 11 years to age 12 years during the initial vaccination series.
                Ages 12 years and older

                COVID-19 vaccination history	Updated 2024-2025 vaccine	Number of 2024-2025 doses indicated	Dosage (mL/ug)	Interval between doses
                Unvaccinated	Moderna	3	0.5 mL/50 ug	Dose 1: Day 0 Dose 2: 4 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                	OR
                	Pfizer-BioNTech	3	0.3 mL/30 ug	Dose 1: Day 0 Dose 2: 3 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                1 dose any Moderna	Moderna	2	0.5 mL/50 ug	Dose 2: 4 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                2 doses any Moderna	Moderna	1	0.5 mL/50 ug	Dose 3: At least 4 weeks after Dose 2 See additional doses
                1 dose any Pfizer-BioNTech	Pfizer-BioNTech	2	0.3 mL/30 ug	Dose 2: 3 weeks after Dose 1 Dose 3: At least 4 weeks after Dose 2 See additional doses
                2 doses any Pfizer-BioNTech	Pfizer-BioNTech	1	0.3 mL/30 ug	Dose 3: At least 4 weeks after Dose 2 See additional doses
                3 or more doses any Moderna or 3 or more doses any Pfizer-BioNTech NOT including at least 1 dose any mRNA 2024–2025 vaccine†	Moderna	1	0.5 mL/50 ug	At least 8 weeks after last dose See additional doses
                	OR
                	Pfizer-BioNTech	1	0.3 mL/30 ug	At least 8 weeks after last dose See additional doses
                3 or more doses any mRNA vaccine INCLUDING at least 1 dose any 2024–2025 vaccine	See additional doses
                1 or more doses any Novavax NOT including 1 dose any 2024–2025 mRNA vaccine	Moderna	1	0.5 mL/50 ug	At least 8 weeks after last dose See additional doses
                	OR
                	Pfizer-BioNTech	1	0.3 mL/30 ug	At least 8 weeks after last dose See additional doses
                ADDITIONAL DOSES: People in this age group may receive 1 additional dose of 2024–2025 mRNA COVID-19 vaccine (i.e., either Moderna or Pfizer-BioNTech, regardless of the manufacturer for the initial series) at least 2 months following the last recommended 2024–2025 vaccine dose. Further additional doses may be administered, informed by the clinical judgment of a healthcare provider and personal preference and circumstances. Any further additional doses should be administered at least 2 months after the last 2024–2025 COVID-19 vaccine dose.

                *Children who transition from age 11 years to age 12 years during the initial vaccination series should complete the 3-dose series using the dosage for people ages 12 years and older for all doses received on or after turning age 12 years:

                • Moderna series: 2024–2025 Moderna, 0.5 mL/50ug
                • Pfizer-BioNTech series: 2024­–2025 Pfizer-BioNTech, 0.3 mL/30 ug

                † This COVID-19 vaccine history refers to previous receipt of 3 doses of mRNA vaccine from the same manufacturer (i.e., Moderna or Pfizer-BioNTech) for initial vaccination followed by 1 or more additional doses of Moderna, Novavax, or Pfizer-BioNTech, excluding receipt of 2024–2025 vaccine for any previous doses.

                Development of moderate or severe immunocompromise after vaccination: People who were vaccinated for COVID-19 and subsequently become moderately or severely immunocompromised should follow the COVID-19 vaccination schedule according to their age and prior COVID-19 vaccination history (Table 2); see Considerations for timing of COVID-19 vaccination in relation to immunosuppressive therapies for vaccination of people who will shortly become moderately or severely immunocompromised (e.g., prior to organ transplant) and Considerations for COVID-19 revaccination.

                COVID-19 vaccination and pemivibart

                Pemivibart (Pemgarda™) is a monoclonal antibody for COVID-19 pre-exposure prophylaxis in people who are moderately or severely immunocompromised and unlikely to mount an adequate immune response to COVID-19 vaccination and who meet the FDA-authorized conditions for use . Pemivibart is not authorized for treatment of COVID-19 or for post-exposure prophylaxis. Healthcare providers should consult the pemivibart EUA fact sheet and EUA frequently asked questions for the FDA-authorized conditions under which pemivibart may be used.

                Pemivibart is not a substitute for COVID-19 vaccination. People who are moderately or severely immunocompromised should receive COVID-19 vaccine according to the recommended schedule. Per the pemivibart EUA , administration of pemivibart should be deferred for at least 2 weeks after a dose of COVID-19 vaccine.

                Description of moderate and severe immunocompromising conditions and treatment

                Moderate and severe immunocompromising conditions and treatments include but are not limited to:

                • Active treatment for solid tumor and hematologic malignancies
                • Hematologic malignancies associated with poor responses to COVID-19 vaccines regardless of current treatment status (e.g., chronic lymphocytic leukemia, non-Hodgkin lymphoma, multiple myeloma, acute leukemia)
                • Receipt of solid-organ transplant or an islet transplant and taking immunosuppressive therapy
                • Receipt of chimeric antigen receptor (CAR)-T-cell therapy or hematopoietic cell transplant (HCT) (within 2 years of transplantation or taking immunosuppressive therapy)
                • Moderate or severe primary immunodeficiency (e.g., common variable immunodeficiency disease, severe combined immunodeficiency, DiGeorge syndrome, Wiskott-Aldrich syndrome)
                • Advanced HIV infection (people with HIV and CD4 cell counts less than 200/mm 3 , history of an AIDS-defining illness without immune reconstitution, or clinical manifestations of symptomatic HIV) or untreated HIV infection
                • Active treatment with high-dose corticosteroids (i.e., 20 mg or more of prednisone or equivalent per day when administered for 2 or more weeks), 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 (e.g., B-cell-depleting agents)

                Factors to consider in assessing the general level of immune competence in a patient include disease severity, duration, clinical stability, complications, comorbidities, and any potentially immune-suppressing treatment.

                For additional information about the degree of immune suppression associated with different medical conditions and treatments, providers can consult ACIP’s General Best Practice Guidelines for Immunizations, the CDC Yellow Book, and the Infectious Diseases Society of America policy statement, 2013 IDSA Clinical Practice Guideline for Vaccination of the Immunocompromised Host .

                Self-attestation of immunocompromised status

                People can self-attest to their moderately or severely immunocompromised status and receive COVID-19 vaccine doses wherever vaccines are offered. Vaccinators should not deny COVID-19 vaccination to a person due to lack of documentation.

                Considerations for COVID-19 revaccination

                Recipients of HCT or CAR-T-cell therapy who received 1 or more doses of COVID-19 vaccine prior to or during treatment should be revaccinated. Revaccination should start at least 3 months (12 weeks) after transplant or CAR-T-cell therapy and should follow the currently recommended schedule for people who are unvaccinated (Table 2).

                Revaccination may also be considered for patients who received 1 or more doses of COVID-19 vaccine during treatment with B-cell-depleting therapies (e.g., rituximab, ocrelizumab) that were administered over a limited period (e.g., as part of a treatment regimen for certain malignancies) according to the currently recommended schedule (Table 2). The suggested interval to start revaccination is about 6 months after completion of the B-cell-depleting therapy. Timing of vaccination for patients who receive B-cell-depleting therapies on a continuing basis (e.g., for treatment of certain autoimmune conditions such as rheumatoid arthritis or multiple sclerosis) is addressed in Considerations for timing of COVID-19 vaccination in relation to immunosuppressive therapies.

                A patient’s clinical team is best positioned to determine the degree of immune compromise, need for revaccination, and appropriate timing of revaccination.

                Considerations for timing of COVID-19 vaccination in relation to immunosuppressive therapies

                Administration of COVID-19 vaccines should not be delayed in patients taking immunosuppressive therapies. Whenever possible, COVID-19 vaccines should be administered at least 2 weeks before initiation or resumption of immunosuppressive therapies. For patients who receive B-cell-depleting therapies on a continuing basis, COVID-19 vaccines should be administered approximately 4 weeks before the next scheduled therapy.

                Timing of COVID-19 vaccination should take into consideration:

                • Current or planned immunosuppressive therapies
                • Optimization of both the patient’s medical condition and anticipated response to vaccination
                • Individual benefits and risks

                On a case-by-case basis, providers caring for these patients may administer Moderna and Pfizer-BioNTech COVID-19 vaccines outside of the FDA and CDC dosing intervals when, based on their clinical judgment, the benefits of vaccination are deemed to outweigh the potential and unknown risks for the recipient who is immunocompromised.

                The utility of serologic testing, cellular immune testing, or B-cell quantification to assess immune response to vaccination and guide clinical care has not been established. Such testing outside of the context of research studies is not recommended at this time.

                Age transitions and simultaneous administration

                Transitioning from a younger to older age group

                CDC recommends that people receive the age-appropriate vaccine product and dosage based on their age on the day of vaccination (Table 1 and Table 2).

                If a person moves to an older age group between vaccine doses , they should receive the vaccine product and dosage for the older age group. For children who transition from age 4 years to age 5 years and children who are moderately or severely immunocompromised and transition from age 11 years to age 12 years, the option to administer a lower dosage is no longer authorized (see Table 1 and Table 2).

                Simultaneous administration of COVID-19 vaccines with other vaccines

                Routine administration of all age-appropriate doses of vaccines simultaneously, also known as coadministration, is recommended for children, adolescents, and adults if there are no contraindications at the time of the healthcare visit. Providers may simultaneously administer COVID-19, influenza, and respiratory syncytial virus (RSV) vaccines to eligible patients; additional information about simultaneous administration of these vaccines is available.

                There are additional considerations for simultaneous administration of an orthopoxvirus vaccine and COVID-19 vaccine as follows:

                • There is no required minimum interval between receiving a dose of any COVID-19 vaccine and an orthopoxvirus vaccine, either JYNNEOS or ACAM2000 vaccine (e.g., for mpox prevention), regardless of which vaccine is administered first.
                • Use of JYNNEOS vaccine should be prioritized over ACAM2000 when co-administering a COVID-19 vaccine and an orthopoxvirus vaccine.
                • People, particularly adolescent or young adult males, who are recommended to receive both vaccines might consider waiting 4 weeks between vaccines. This is because of the observed risk for myocarditis and pericarditis after receipt of ACAM2000 orthopoxvirus vaccine and COVID-19 vaccines, and the hypothetical risk for myocarditis and pericarditis after JYNNEOS vaccine. However, if a patient’s risk for mpox or severe disease due to COVID-19 is increased, administration of mpox and COVID-19 vaccines should not be delayed.

                Nirsevimab: Simultaneous administration of COVID-19 vaccine and nirsevimab (a long-acting monoclonal antibody indicated for certain infants and young children for prevention of RSV lower respiratory tract disease) is recommended.

                Interchangeability of COVID-19 vaccines

                Administration of COVID-19 vaccine doses from different manufacturers

                COVID-19 vaccine doses from the same manufacturer should be administered whenever recommended. In the following circumstances, an age-appropriate COVID-19 vaccine from a different manufacturer may be administered:

                • Same vaccine not available at the time of the clinic visit
                • Previous dose unknown
                • Person would otherwise not receive a recommended vaccine dose
                • Person starts but unable to complete a vaccination series with the same COVID-19 vaccine due to a contraindication

                A Vaccine Adverse Event Reporting System (VAERS) report is not indicated in these circumstances.

                mRNA COVID-19 vaccines

                If mRNA vaccine doses are administered from different manufacturers because of a circumstance described above, a 3-dose schedule should be followed:

                Children ages 6 months–4 years

                • The second dose is administered 4–8 weeks after the first dose.
                • The third dose of either 2024–2025 Moderna vaccine or 2024–2025 Pfizer-BioNTech vaccine is administered at least 8 weeks after the second dose.

                People ages 6 months and older who are moderately or severely immunocompromised

                • The second dose is administered 4 weeks after the first dose.
                • The third dose of either 2024–2025 Moderna vaccine or 2024–2025 Pfizer-BioNTech vaccine is administered as follows:
                • • Ages 6 months–4 years: at least 8 weeks after the second dose
                  • Ages 5 years and older: at least 4 weeks after the second dose

                  See Appendix B for additional information if doses from different manufacturers are administered for initial vaccination.

                  COVID-19 vaccination and SARS-CoV-2 laboratory testing

                  Antibody testing is not currently recommended to assess the need for vaccination in an unvaccinated person or to assess immunity to SARS-CoV-2 following COVID-19 vaccination or SARS-CoV2 infection. If antibody testing is done, vaccination should proceed as recommended regardless of the antibody test result.

                  COVID-19 vaccination will not affect the results of SARS-CoV-2 viral tests (nucleic acid amplification or antigen tests).

                  Patient counseling

                  Pre-vaccination counseling

                  Providers should counsel COVID-19 vaccine recipients, parents, or guardians about expected local and systemic reactions.

                  • Local reactions include pain/tenderness, and, less commonly, swelling and redness at the injection site.
                  • Systemic reactions include fever, fatigue/malaise, headache, chills, myalgia, arthralgia, and diarrhea; among younger children, particularly those younger than age 3 years, systemic reactions also can include irritability/crying, sleepiness, and loss of appetite.

                  Localized axillary lymphadenopathy on the same side as the vaccinated arm or groin, if vaccination was in the thigh, has been observed following vaccination with Moderna, Novavax, and Pfizer-BioNTech COVID-19 vaccines. Infrequently, people who have received dermal fillers might experience temporary swelling at or near the site of filler injection (usually face or lips) following a dose of an mRNA COVID-19 vaccine.

                  Myocarditis and pericarditis: People receiving any COVID-19 vaccine, especially males ages 12–39 years, should be made aware of the rare risk of myocarditis and pericarditis following COVID-19 vaccination and the option for an extended interval between doses. Counseling should include the need to seek care if symptoms of myocarditis or pericarditis develop after vaccination, particularly in the week after vaccination. See COVID-19 vaccination and myocarditis and pericarditis for additional information.

                  Anaphylactic reactions: Anaphylactic reactions have been rarely reported following receipt of COVID-19 vaccines. For more information on the assessment and potential management of anaphylaxis, see Preparing for the Potential Management of Anaphylaxis after COVID-19 Vaccination.

                  For more information on patient counseling, see Vaccine Recipient Education.

                  Post-vaccination observation period

                  Syncope (fainting) might occur in association with any injectable vaccine, especially in adolescents. In accordance with General Best Practice Guidelines for Immunization, vaccination providers, particularly when vaccinating adolescents, should consider observing vaccine recipients for 15 minutes after vaccination.

                  Additionally, to monitor for allergic reactions, providers should consider observing people with the following precautions to a previously administered COVID-19 vaccine type for 30 minutes if a subsequent dose of the same vaccine type is administered:

                  • History of a non-severe, immediate (onset less than 4 hours) allergic reaction after administration of a previous dose of one COVID-19 vaccine type
                  • History of a diagnosed non-severe allergy to a component of the COVID-19 vaccine

                  Contraindications and precautions

                  CDC considers the conditions listed in Table 3 to be COVID-19 vaccination contraindications and precautions.

                  Table 3. Contraindications and precautions to COVID-19 vaccination

                  Table 3. Contraindications and precautions to COVID-19 vaccination

                  Medical condition or history	Guidance	Recommended action
                  History of a severe allergic reaction* (e.g., anaphylaxis†) after a previous dose or to a component of the COVID-19 vaccine ‡	Contraindication	Do not vaccinate with the same COVID-19 vaccine type. §

                  May administer the alternate COVID-19 vaccine type. §

                  Abbreviations: MIS-C = multisystem inflammatory syndrome in children; MIS-A = multisystem inflammatory syndrome in adults

                  *Allergic reactions in Table 3 are defined as follows:

                  Severe allergic reactions include: known or possible anaphylaxis, a progressive life-threatening reaction that typically includes urticaria (hives) but also with other symptoms such as wheezing, difficulty breathing, or low blood pressure; angioedema (visible swelling) affecting the airway (i.e., tongue, uvula, or larynx); diffuse rash which also involves mucosal surfaces (e.g., Stevens-Johnson Syndrome).

                  Non-severe allergic reactions include but are not limited to: urticaria beyond the injection site; angioedema involving lips, facial skin, or skin in other locations. NOTE: Any angioedema affecting the airway (i.e., tongue, uvula, or larynx) is considered a severe allergic reaction.

                  † Anaphylactic reactions have been rarely reported following receipt of COVID-19 vaccines (estimated incidence: 5 per million doses of mRNA COVID-19 vaccines administered ). For more information on the assessment and potential management of anaphylaxis, see Preparing for the Potential Management of Anaphylaxis after COVID-19 Vaccination.

                  ‡ See package inserts and EUA fact sheets for a full list of vaccine ingredients. mRNA COVID-19 vaccines contain polyethylene glycol (PEG).

                  § The mRNA COVID-19 vaccines (Moderna and Pfizer-BioNTech) are one type of COVID-19 vaccine and the protein subunit vaccine (Novavax) is another type of COVID-19 vaccine.

                  Considerations for people with a history of allergies or allergic reactions

                  People with a contraindication to one COVID-19 vaccine type (Table 3) may receive the alternative COVID-19 vaccine type in the usual vaccination setting. Consultation with an allergist-immunologist is encouraged to provide expert evaluation of the original allergic reaction, and depending on the outcome of the evaluation, reassess if administration of additional doses of the same vaccine type may be possible.

                  People with an allergy-related precaution to one COVID-19 vaccine type (Table 3) may receive the alternative COVID-19 vaccine type in the usual vaccination setting. Vaccination with the same COVID-19 vaccine type may be considered on an individual basis; the same vaccine type should be administered in an appropriate setting and under the supervision of a health care provider experienced in the management of severe allergic reactions. An observation period of 30 minutes post-vaccination should be considered. Referral to an allergist-immunologist should be considered.

                  Healthcare professionals and health departments may request a consultation from CDC’s Clinical Immunization Safety Assessment COVIDvax project for a complex COVID-19 vaccine safety question not readily addressed by CDC guidance.

                  Reporting of vaccine adverse events

                  For licensed COVID-19 vaccines (Moderna and Pfizer-BioNTech in people ages 12 years and older), healthcare providers are strongly encouraged to report to VAERS :

                  • Any adverse event that occurs after the administration of a vaccine licensed in the United States, whether or not it is clear that a vaccine caused the adverse event
                  • Vaccine administration errors, whether or not associated with an adverse event

                  For COVID-19 vaccines given under an EUA, vaccination providers are required to report to VAERS :

                  • Vaccine administration errors, whether or not associated with an adverse event
                  • Serious adverse events regardless of causality. Serious adverse events per FDA are defined as:
                    • Death
                    • A life-threatening adverse event
                    • Inpatient hospitalization or prolongation of existing hospitalization
                    • A persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions
                    • A congenital anomaly/birth defect
                    • An important medical event that based on appropriate medical judgement may jeopardize the individual and may require medical or surgical intervention to prevent one of the outcomes listed above

                    Reporting is also encouraged for any other clinically significant adverse event, even if it is uncertain whether the vaccine caused the event.

                    Information on how to submit a report to VAERS is available at https://vaers.hhs.gov or by calling 1-800-822-7967. In addition, anyone can register in V-safe after their COVID-19 vaccination to receive health check-ins via text messages or email.

                    Safety considerations for mRNA COVID-19 vaccines: Moderna and Pfizer-BioNTech

                    In clinical trials of Moderna and Pfizer-BioNTech COVID-19 vaccines, types of post-vaccination reactions were generally similar. However, the frequency of some reactions varied by age, vaccine manufacturer, and vaccine dose. The most frequent reported reactions, by age group, follow below.

                    People ages 12 years and older

                    • Local: Injection site pain; less commonly, injection site redness and swelling, and axillary swelling/tenderness
                    • Systemic: Fatigue, headache, myalgia, arthralgia, and chills; less commonly, fever and nausea/vomiting

                    Overall, symptoms tended to be more frequent and severe following the second dose of vaccine and among adolescents and younger adults compared with older adults.

                    Children ages 6 months–11 years

                    • Local: Injection site pain/tenderness; less commonly, injection site redness and swelling, and axillary or groin swelling/tenderness
                    • Systemic:
                      • Ages 6 months–4 years: Irritability/crying, drowsiness/sleepiness, and decreased/loss of appetite, particularly in children younger than age 3 years; less commonly, fever
                      • Ages 5–11 years: Fatigue and headache; less commonly, myalgia, arthralgia, fever, chills, diarrhea, and nausea/vomiting

                      In all age groups, most symptoms were mild to moderate in severity, typically began 1–2 days after vaccination, and resolved after 1–3 days.

                      EUA fact sheets and package inserts can be consulted for detailed information about post-vaccination reactions for Moderna and Pfizer-BioNTech COVID-19 vaccines.

                      Febrile seizures in infants and young children occur infrequently after any vaccination; one febrile seizure was reported among participants ages 6 months–23 months in Moderna’s COVID-19 clinical trial . CDC postmarketing safety surveillance for mRNA COVID-19 vaccines has not identified a safety concern for febrile seizure in children ages 6 months–5 years. The potential impact of simultaneous administration of COVID-19 and routine vaccines on the risk of febrile seizures has not been specifically studied. CDC is continuing to monitor for febrile seizures following COVID-19 vaccination in infants and young children.

                      Safety considerations for Novavax COVID-19 Vaccine

                      In clinical trials of Novavax COVID-19 Vaccine among people ages 12 years and older, the most frequent reported vaccine reactions included:

                      • Local: Pain/tenderness at the injection site; less commonly, redness and swelling
                      • Systemic: Fatigue/malaise, headache, and myalgia; less commonly, arthralgia, nausea/vomiting, and fever

                      In addition, lymphadenopathy was also reported to occur after Novavax vaccination in the clinical trials.

                      Most symptoms were mild to moderate in severity, had onset 1-3 days after vaccination, and resolved within 1–3 days. Overall, symptoms were more frequent in people ages 12–64 years compared to people ages 65 years and older and more frequent after dose 2 than dose 1 of the initial vaccination series.

                      The EUA fact sheet can be consulted for detailed information about post-vaccination reactions for Novavax COVID-19 Vaccine.

                      COVID-19 vaccination and myocarditis and pericarditis

                      Considerations for COVID-19 vaccination

                      Cases of myocarditis and pericarditis have rarely been observed following receipt of COVID-19 vaccines used in the United States.

                      Evidence from multiple monitoring systems in the United States and globally support a causal association for mRNA COVID-19 vaccines (Moderna or Pfizer-BioNTech) and myocarditis and pericarditis. Cases have occurred most frequently in adolescent and young adult males within 7 days after receiving the second dose of an mRNA COVID-19 vaccine (Moderna and Pfizer-BioNTech); however, cases have also been observed in females and after other doses. Data from clinical trials of Novavax COVID-19 Vaccine and post-authorization vaccine safety monitoring outside the United States suggest an increased risk of myocarditis and pericarditis following Novavax vaccination.

                      For mRNA COVID-19 vaccines and Novavax COVID-19 Vaccine:

                      • After reviewing available data, ACIP and CDC determined that the benefits of COVID-19 vaccination (e.g., prevention of COVID-19 and its severe outcomes) outweigh the rare risk of myocarditis and pericarditis in all populations recommended for vaccination.
                      • Extending the interval to 8 weeks between the first and second doses for some people might reduce the rare risk of vaccine-associated myocarditis and pericarditis; see Considerations for extended intervals for COVID-19 vaccination for more information.
                      • People, especially males ages 12–39 years, should be made aware of the rare risk of myocarditis and pericarditis following receipt of these vaccines; the option for an extended interval between doses; and the benefit of COVID-19 vaccination in reducing the risk of severe outcomes from COVID-19, including the possibility of cardiac sequelae.
                        • Counseling should include the need to seek care if symptoms of myocarditis or pericarditis, such as chest pain, shortness of breath, or palpitations develop after vaccination, particularly in the week after vaccination.
                        • In younger children, symptoms of myocarditis might also include non-specific symptoms such as irritability, vomiting, poor feeding, tachypnea, or lethargy.

                        For people who have a history of myocarditis associated with MIS-C or MIS-A, see COVID-19 vaccination and MIS-C and MIS-A.

                        Myocarditis or pericarditis after a dose of COVID-19 vaccine

                        Development of myocarditis or pericarditis within 3 weeks after a dose of any COVID-19 vaccine is a precaution to a subsequent dose of any COVID-19 vaccine, and subsequent doses should generally be avoided. Experts advise that these people should:

                        • Generally notreceive a subsequent dose of any COVID-19 vaccine
                        • If, after a risk assessment, the decision is made to administer a subsequent COVID-19 vaccine dose, wait until at least their episode of myocarditis or pericarditis has resolved (resolution of symptoms, no evidence of ongoing heart inflammation or sequelae as determined by patient’s clinical team)

                        Considerations for subsequent COVID-19 vaccination might include:

                        • Myocarditis or pericarditis considered unrelated to vaccination (e.g., due to SARS-CoV-2 or other viruses)
                        • Personal risk of severe acute COVID-19 (e.g., age, underlying conditions)
                        • Timing of any immunomodulatory therapies; ACIP’s General Best Practice Guidelines for Immunization can be consulted for more information

                        History of myocarditis or pericarditis that occurred prior to COVID-19 vaccination or more than 3 weeks after a COVID-19 vaccine dose

                        People who have a history of myocarditis or pericarditis that occurred before COVID-19 vaccination or more than 3 weeks after a COVID-19 vaccine dose may receive any currently FDA-approved or FDA-authorized COVID-19 vaccine after the episode of myocarditis or pericarditis has completely resolved (i.e., resolution of symptoms, no evidence of ongoing heart inflammation or sequelae as determined by the person’s clinical team). This includes people who had myocarditis or pericarditis due to SARS-CoV-2 or other viruses.

                        History of other heart disease

                        People who have a history of other heart disease, including congenital heart disease and Kawasaki disease, may receive any currently FDA-approved or FDA-authorized COVID-19 vaccine.