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Primary Series and Boosters

The CDC recommends everyone stay up to date with COVID-19 vaccination, including all primary series doses and boosters for their age group:

  • People ages 6 months through 4 years should get all COVID-19 primary series doses.
  • People ages 5 years and older should get all primary series doses, and the updated booster dose recommended for them by CDC, if eligible.
    • People ages 5 years and older are recommended to receive one updated Pfizer or Moderna (bivalent) booster.
      • This includes people who have received all COVID-19 primary series doses and people who have previously received one or more original (monovalent) boosters.
      • At this time, people aged 5 years and older can receive the updated Pfizer bivalent booster and people 6 years and older can receive the updated Moderna bivalent booster.

Frequently Asked Questions

What is the difference between the primary series and booster dose?

Primary series:
• For most people, 2-dose series of an mRNA COVID-19 vaccine (Pfizer-BioNTech and Moderna) or a single dose of Janssen Vaccine.
• For people who are moderately or severely immunocompromised, a 3-dose series of an mRNA COVID-19 vaccine or a single dose of Janssen COVID-19 Vaccine.

Booster dose: A subsequent dose of vaccine administered to enhance or restore protection which might have waned over time after primary series vaccination.

The CDC now recommends for certain groups of people who are considered to be moderately to severely immunocompromised (ie. have a weakened immune system) to receive a third primary series dose of the COVID-19 vaccine. Some example of a weakened immune system include:

• 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

People should talk to their healthcare provider about their medical condition, and whether getting an additional dose is appropriate for them. See criteria here.

The FDA has authorized the updated booster for Moderna in individuals 6 years older and for Pfizer in individuals 5 years and older. Everyone 5 years and older who has received their primary series should get the updated booster at least 2 months following any COVID-19 vaccine or booster dose.

  • The updated boosters are available for everyone aged 5+
  • Following completion of their primary series, regardless of vaccine product used
  • Regardless of the number of booster doses received
  • And are the only mRNA booster doses that are available to them. Those 5+ are no longer eligible for the current mRNA boosters based only on the original strain of the virus.

It is recommended that everyone 5 years and older get boosted, if eligible, with the age appropriate vaccine that is available to them.

There is no required proof outside of a self-attestation. A self-attestation is a statement indicating that you have self-determined that you are eligible to receive a third primary dose of a COVID-19 vaccine.

Self-attestation forms are available at every County-run vaccine clinic. To view the self-attestation, please see the following:

Pfizer-BioNTech (Comirnaty) vaccine and Moderna (Spikevax) are available for booster doses.

When possible, you should receive the same COVID-19 vaccine. However, if in an eligible age group, the booster doses may be administered as a mix and match (heterologous) following completion of a primary vaccine series. Eligibility requirements and dosing intervals remain the same regardless of which booster dose is selected.

Examples:

  • If aged 12 years or older, those who received Moderna as their primary series, should receive the Updated Booster dose of Pfizer.
  • If aged 18 or older, those who received Johnson & Johnson for their primary series, should receive the Updated Booster dose of Moderna or Pfizer.

Per the Western States Scientific Safety Review Workgroup:

“Individuals who have previously received an initial series of any of the three COVID-19 vaccines currently approved or authorized for use in the United States are eligible for a booster dose. The Workgroup supports CDC’s decision that individuals eligible for a booster may receive either the same or a different COVID-19 vaccine as a booster dose, depending on advice from a health care provider, individual preference, availability or convenience.”

Please refer to the following media statement from the CDC on Booster Shot Mixing and Matching and the Western States Scientific Safety Review Workgroup statement.

Contact your provider directly to confirm if you need to bring your vaccine card.

If you make an appointment at an SB County Vaccine Clinic or special pop-up event please bring your vaccine card.

If you have lost your vaccine card please refer to the County’s COVID-19 Vaccine Cards page.

If you are moderately or severely immunocompromised, being up to date means you have completed a three-dose primary series and received the most recent booster dose recommended for you.

You are also considered up to date if, you have completed your primary series but are not yet eligible for a booster.

Please see the COVID-19 Vaccine Eligibility Chart.

Yes, people who are pregnant are eligible and encouraged to receive a booster dose. People who are pregnant or recently pregnant are more likely to get severely ill with COVID-19 compared with people who are not pregnant. Find more resources on CDPH’s Pregnancy and COVID-19 Vaccines website.

FDA Authorizations for Healthcare Providers and Fact Sheets for Patients

Pfizer-BioNTech (Comirnaty) Fact Sheet:
For Recipients and Caregivers

Moderna (Spikevax) Fact Sheet:
For Recipients and Caregivers

Janssen Fact Sheet:
For Recipients and Caregivers

Novavax Fact Sheet:
For Recipients and Caregivers

COVID-19 Boosters California Department of Public Health (CDPH) Recommendation
(Updated as of Oct. 20, 2022)

What:

The FDA has authorized the updated booster for Moderna for adults 6 years and older and for Pfizer for those 5 years and older. Everyone 5+ who has had their primary series should get the updated booster at least 2 months following any COVID vaccine or booster dose.

The updated boosters are available for everyone aged 5+:

  • Following completion of their primary series, regardless of vaccine product used
  • Regardless of the number of booster doses received
  • And are the only mRNA booster doses that are available to them. Those 5+ are no longer eligible for the current mRNA boosters based only on the original strain of the virus.

The previous boosters were monovalent and contained one strain while the updated boosters are bivalent and add the Omicron strains that have been causing the most recent cases.

Please see below for a brief description of who is eligible. For a more detailed outline including any special situations for those who are immunocompromised, please see the COVID-19 Vaccine Eligibility Chart.

For more information on Booster and Additional Doses, see Related Materials.

Eligibility:

Pfizer-BioNTech (Pfizer)

6 months through 4 years:

  • Regardless of Immune Response:
    • No recommendation for any booster or additional doses at this time.

5 years and older

  • Regular Immunity:
    • Should receive the Updated Booster (bivalent) dose of Pfizer at least two months after receiving their last dose, regardless of type (primary series or booster).
  • Compromised Immunity:
    • Should receive an additional (monovalent) dose of Pfizer at least four weeks after receiving the second dose in their primary series.
    • Should receive the Updated Booster (bivalent) dose of Pfizer at least two months after receiving their last dose, regardless of type (primary series or booster).

Moderna

6 months through 5 years

  • Regular Immunity:
    • No recommendation for any booster doses at this time.
  • Compromised Immunity:
    • Should receive an additional (monovalent) dose of Moderna at least four weeks after receiving the second dose of their primary series.
    • No recommendation for any booster doses at this time.

6  years and older

  • Regular Immunity:
    • Should receive the Updated Booster (bivalent) dose of Pfizer at least two months after receiving their second dose.
  • Compromised Immunity:
    • Should receive an additional (monovalent) dose of Moderna at least four weeks after receiving the second dose in their primary series.
    • Should receive the Updated Booster (bivalent) dose of Pfizer at least two months after receiving their additional/third dose of the primary series.

Novavax COVID-19 Vaccine, Adjuvanted (Novavax)

12 years+

  • Regardless of Immune Response:
    • Should receive the Updated Booster (bivalent) dose at least two months after their last dose, regardless of type (primary series or booster).

18 years+

  • Regardless of Immune Response:
    • Should receive the Updated Booster (bivalent) dose at least two months after their last dose, regardless of type (primary series or booster).
    • In some limited situations, may receive the Novavax booster dose at least six months after completion of their primary series. Only for people for whom an mRNA Updated Booster is not accessible or clinically appropriate, or who would otherwise not receive a booster dose. 

Johnson & Johnson (J&J)

18 years+

  • Regular Immunity:
    • Should receive the Updated Booster (bivalent) dose at least two months after their last dose, regardless of type (primary series or booster) or may receive a J&J booster (monovalent) dose.
  • Compromised Immunity:
    • Should receive an additional (monovalent) dose of an mRNA vaccine at least four weeks after receiving the second dose of their primary series.
    • Should receive the Updated Booster (bivalent) dose at least two months after receiving their last dose, regardless of type (primary series or booster).
Where:

Booster doses are available in many places, including healthcare provider offices, clinics and local pharmacies. Californians can visit the My Turn webpage (MyTurn.ca.gov) or call (833) 422-4255, or visit Vaccines.gov to make an appointment or find a walk-in vaccine clinic near them.