Anthony Fauci
Anthony FauciReuters

Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, estimates that babies and toddlers aged 6 months to 5 years could be eligible for COVID-19 vaccination by spring, though he "can't guarantee it".

Fauci made the remarks in an interview with Insider on Thursday.

"Hopefully within a reasonably short period of time, likely the beginning of next year in 2022, in the first quarter of 2022, it will be available to them," he said, though he cautioned that he was speculating, adding, "you've got to do the clinical trial."

Pfizer-BioNTech have stated that results from their clinical trial in children in the age ranges of 2 to 5 years and 6 months to 2 years are expected as soon as the fourth quarter of this year, according to The Hill.

According to a report by ABC Tampa in late October, Pfizer expects to apply this month for approval for its COVID-19 vaccine in children ages 6 months to 5 years, the last age range in the US not yet being vaccinated.

According to CNN, Pfizer is the furthest along in trials for those aged 6 months to 5 years, but Moderna is also conducting studies in very young children.

The FDA most recently authorized Pfizer and BioNTech’s COVID-19 vaccine for children ages 5 to 11.

The vaccine is administered as a two-dose primary series, 3 weeks apart, but is a lower dose, 10 micrograms, than that used for individuals 12 years of age and older which is 30 micrograms.

The White House announced Wednesday that 10 percent of children ages 5 to 11 have received their first coronavirus shot, following the approval of the Pfizer pediatric dose.