The CDC has issued a recommendation for updated boosters for children aged 6 months to 4 years who have completed their three-dose primary series with the original Pfizer-BioNTech COVID-19 vaccine.

Updates on federal efforts to increase nursing home resident bivalent booster uptake, availability of single-dose vaccine vials, and expansion of use of bivalent vaccines to children ages six months through five years.

Vaccination recommended two months after second primary vaccine or any booster dose.

Distribution of vaccines for children under age 5 has begun.

The CDC now recommends a second booster for adults age 50 and over when four months have elapsed since the first booster. The stronger recommendation was accompanied by a new definition of "up to date" with vaccinations. Under the new definition, adults age 50 and over are "up to date" when they have received a second booster if eligible.

A single booster is still the recommendation for the general population.