Moderately or severely immunocompromised people age 5 to 11 who received the pediatric Pfizer COVID-19 vaccine for their primary series should:

• receive an additional primary dose of Pfizer at least 28 days after their second Pfizer dose.
• receive a single Pfizer booster dose at least 5 months after completing their third Pfizer dose.

Moderately or severely immunocompromised people age 12 or older who received an initial mRNA COVID-19 vaccine primary series should:

• receive an additional primary dose of the same mRNA COVID-19 vaccine at least 28 days after the second mRNA dose.
• receive an age-appropriate mRNA COVID-19 booster dose (Pfizer or Moderna) at least 3 months after completing their third mRNA vaccine dose.
• receive a second, age-appropriate mRNA COVID-19 booster dose at least 4 months after completing their fourth mRNA vaccine dose.

Moderately or severely immunocompromised people age 18 or older who received an initial Johnson & Johnson COVID-19 vaccine for their primary vaccination should:

• receive an additional dose of an mRNA vaccine (Pfizer or Moderna) at least 28 days after their first Johnson & Johnson dose.
• receive an initial mRNA COVID-19 booster dose (Pfizer or Moderna) at least 2 months after completing their first mRNA vaccine dose.
• receive a second mRNA COVID-19 booster dose at least 4 months after completing their second mRNA vaccine dose.

People age 5 to 17 must receive the Pfizer vaccine as it is the only vaccine approved for this age group. For primary and booster vaccination, people should receive an age-appropriate mRNA vaccine (Pfizer or Moderna). The Johnson & Johnson vaccine is authorized for anyone age 18 and older if no other approved vaccine is available.

A patient’s clinical team is best positioned to determine the appropriate timing of vaccination.