The only vaccine available for children has been Pfizer-BioNTech’s, authorized for those 5 and up. Traditionally, drugs and vaccines are studied first in adults and then in adolescents and progressively younger children, moving down in age as safety and effectiveness are proven in older groups.
Babies younger than 6 months are not expected to receive a COVID-19 vaccine. Instead, vaccination during pregnancy, which has shown to be safe, passes on protection that lasts for about the first six months of life.
With the COVID-19 vaccines, companies took time to determine the most effective doses for each eligible age group, while minimizing side effects.
Pfizer-BioNTech offers adults and adolescents a two-dose initial vaccine series, with 30 micrograms of active ingredients in each shot. Children ages 5-11 receive 10 micrograms of the vaccine and the youngest children would get a 3 microgram dose.
Pfizer and its German partner BioNTech found that two doses was not adequately protective against the omicron variant, so they are asking the FDA and CDC to authorize a three-dose series for children ages 6 months through 4 years old. Older children are already authorized to receive a booster dose to protect against the latest variants.
With the Moderna vaccine, which is based on the same mRNA technology as Pfizer-BioNTech’s, adults get two 100-microgram doses for their initial series. The company proposed the same dosage for teens, two 50-microgram shots for younger children and two 25-microgram doses for the youngest children.
Moderna only tested its vaccine in two doses and it appears less effective in the youngest children.