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With FDA’s authorization, the monovalent mRNA COVID-19 vaccines are not authorized as booster doses for individuals 12 years of age and older. Appointments for individuals 12 years of age and older for previously-authorized monovalent Pfizer-BioNTech or Moderna boosters need to be rescheduled for when locations have the bivalent COVID-19 vaccines available. 
Both mRNA monovalent vaccines remain authorized for primary series use, and the monovalent Pfizer-BioNTech COVID-19 vaccine may be used as a single booster dose in individuals 5 through 11 years of age.
 
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The virus that causes COVID-19 changes over time. Keep your protection up to date by getting an updated COVID-19 vaccine booster. The updated COVID-19 vaccine boosters include components of the original virus strain and the Omicron variant. This is called a bivalent COVID-19 vaccine.
The updated COVID-19 vaccine boosters are designed to give you broad protection against COVID-19, including better protection against the Omicron variant.
COVID-19 vaccines can help protect against severe illness, hospitalization and death from COVID-19. As the virus changes and your immunity naturally decreases over time, you may lose some of that protection.
The updated (bivalent) booster vaccines are authorized to help provide better protection against COVID-19.
The FDA authorized bivalent formulations of the Moderna and Pfizer-BioNTech COVID-19 vaccines for use as a single booster dose at least two months after completing primary or booster vaccination.
The Moderna COVID-19 Vaccine, Bivalent is authorized for use as single booster dose in individuals 18 years of age and older.
The Pfizer-BioNTech COVID-19 Vaccine, Bivalent is authorized for use as a single booster dose in individuals 12 years of age and older.
Eligibility for a booster depends on:
A single booster dose with an updated bivalent COVID-19 vaccine is designed to provide broad protection against COVID-19 and better protection against COVID-19 caused by the currently circulating Omicron variant.
If you are eligible for an updated COVID-19 vaccine booster, the updated booster you receive does not need to be from the same manufacturer that made the vaccine you received for your primary vaccination or previous booster.

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