TAMPA, Fla. (WFLA) — The U.S. Food and Drug Administration updated the emergency authorization for both mRNA COVID-19 vaccines. The updated two-shot regimen policy now allows for vaccination of children as young as 6 months old.

Both bivalent vaccination regimens have been given clearance for use for children 6 months old to 5 years old. Previously, the emergency use authorizations for both the Moderna and Pfizer vaccines were limited to patients 5 years of age or older.

Going forward, vaccine approval on the EUA guidelines also includes boosters for young patients. However, the FDA noted differences in dose counts between the two mRNA vaccines.

Young patients who received Moderna vaccinations were given a single dose, or a monovalent vaccine, while patients who had gotten the Pfizer version may have been given as many as three doses for what’s called their “primary series” vaccines.

Going forward, the FDA provided the following information for dose regimens, while giving warnings about the risk of myocarditis and pericarditis for vaccine recipients. More information on the booster doses for child patients is expected in January 2023.

  • Children 6 months through 5 years of age who received the original (monovalent) Moderna COVID-19 Vaccine are now eligible to receive a single booster of the updated (bivalent) Moderna COVID-19 Vaccine two months after completing a primary series with the monovalent Moderna COVID-19 Vaccine.
  • Children 6 months through 4 years of age who have not yet begun their three-dose primary series of the Pfizer-BioNTech COVID-19 Vaccine or have not yet received the third dose of their primary series will now receive the updated (bivalent) Pfizer-BioNTech COVID-19 vaccine as the third dose in their primary series following two doses of the original (monovalent) Pfizer-BioNTech COVID-19 Vaccine.
  • Children 6 months through 4 years of age who have already completed their three-dose primary series with the original (monovalent) Pfizer-BioNTech COVID-19 Vaccine will not be eligible for a booster dose of an updated bivalent vaccine at this time. Children in this age group who already completed their primary series would still be expected to have protection against the most serious outcomes from the currently circulating omicron variant.
  • The Moderna and Pfizer-BioNTech bivalent COVID-19 vaccines include an mRNA component corresponding to the original strain to provide an immune response that is broadly protective against COVID-19 and an mRNA component corresponding to the omicron variant BA.4 and BA.5 lineages to provide better protection against COVID-19 caused by the omicron variant. 
  • Individuals who receive the updated (bivalent) vaccines may experience similar side effects reported by individuals who received previous doses of the original (monovalent) mRNA COVID-19 vaccines.
  • The fact sheets for both bivalent COVID-19 vaccines for recipients and caregivers and for healthcare providers include information about the potential side effects, as well as the risks of myocarditis and pericarditis. 

“Vaccines remain the best defense against the most devastating consequences of disease caused by the currently circulating omicron variant, such as hospitalization and death. Based on available data, the updated, bivalent vaccines are expected to provide increased protection against COVID-19,” Peter Marks, M.D., Ph.D., director of the FDA’s Center for Biologics Evaluation and Research, said in a statement in part.

Marks also included assurance to parents and caregivers that the vaccines were reviewed carefully, and that getting the booster now while COVID-19 cases are increasing could “potentially help protect” their children from the virus. FDA Commissioner Robert M. Califf, M.D. also said the updated guidance allows more children to opportunity to be protected against COVID-19.

“As this virus has changed, and immunity from previous COVID-19 vaccination wanes, the more people who keep up to date on COVID-19 vaccinations, the more benefit there will be for individuals, families and public health by helping prevent severe illnesses, hospitalizations, and deaths,” Califf said in part. Additional notes on both the Moderna and Pfizer vaccines for COVID-19 can be read on the FDA EUA notice.