Last month, Pfizer & BioTech received FDA authorization to give children under 5 years old the Omicron BA.4/BA.5-adapted COVID-19 booster. According to a Pfizer press release, “Safety and immunogenicity were assessed in a subset of study participants 6 months through 4 years of age.” Pfizer and BioNTech have also applied to the European Medicines Agency (EMA) to extend the booster’s marketing authorization to include use in children 6 months–4 years of age. Currently, the booster is authorized in the European Union for children ages five and older.