A third dose of an mRNA vaccine [Comirnaty (Pfizer) for 5 and older or Spikevax (Moderna) for 18 and older] is approved for people who have moderately to severe immunocompromised conditions. People between the ages of 5 and 17 must receive the Pfizer vaccine as it is the only vaccine approved for their age group. The third dose should be administered at least 28 days after the second dose. Speak with a pediatrician for more information.
See additional recommendations for people who are moderately to severely immunocompromised.