As Pfizer and BioNTech announced on Monday that their COVID vaccine had a “robust” response in children aged 5 to 11, the nation’s leading infectious disease expert assessed that the shot would likely be made available for young kids before Halloween.

Dr. Anthony Fauci, who is President Joe Biden’s chief medical advisor, said during an interview with MSNBC that “there’s a really good chance it will be” available before the Oct. 31 holiday, Bloomberg reported.

Pfizer’s and BioNTech’s COVID vaccine for children provides two 10 mg doses of the shot 21 days apart in what the companies said produced a strong antibody response during test trials with similar side effects seen in those aged 16 to 25.

Former Food and Drug Administration Commissioner Dr. Mark McClellan agreed with Fauci’s assessment, also saying kids realistically could be getting vaccinated in a month based on the new data released by Pfizer on Monday.

McClellan, who is a health policy expert at Duke University, told CNBC’s “The News With Shepard Smith,” “Those findings are very promising, especially around the ability of a very small dose, leading to a very strong immune reaction. So, it’s good that that’s panning out and action by the FDA in a month seems very feasible.”

Children make up nearly 30% of all new COVID cases nationwide, up from 15% of cases in January, according to the American Academy of Pediatrics, as reported by CNBC.

Pfizer and BioNTech said they are submitting the vaccine data for FDA authorization as soon as possible.

To date, over 221 million Pfizer-BioNTech COVID vaccine doses have been administered to eligible Americans.

The United States began inoculating teens -- like 13-year-old Charles Muro in Connecticut -- with Pfizer-BioNTech's Covid-19 vaccine in May 2021, and Moderna is now the second firm to seek a US green light to administer its shot to adolescents
The U.S. began inoculating teens -- like 13-year-old Charles Muro in Connecticut -- with Pfizer-BioNTech's Covid-19 vaccine in May 2021, and Moderna is now the second firm to seek a U.S. green light to administer its shot to adolescents. AFP / Joseph Prezioso