The U.S. is expected to start COVID-19 vaccination this week for children as young as 6 months old, after the U.S. Centers for Disease Control and Prevention (CDC) signed off on the shots for an additional 19 million children across the country.

The CDC's advisory panel unanimously recommended the Pfizer-BioNTech vaccine for children ages 6 months to 4 years on June 18, as well as the Moderna vaccine for children ages 6 months through 5 years.

"We know millions of parents and caregivers are eager to get their young children vaccinated, and with today's decision, they can," said CDC Director Rochelle Walensky in a statement.

The CDC's move came a day after the U.S. Food and Drug Administration amended emergency use authorizations for the two vaccines to include the youngest age group, and this was the last age group in the U.S. without access to a COVID-19 vaccine.

Since the pandemic began, more than 13.5 million U.S. kids have tested positive for the coronavirus, according to the latest report of the American Academy of Pediatrics and the Children's Hospital Association.

Although COVID-19 is normally less severe in children than adults, the virus can be life-threatening for some kids. COVID-19 is the fifth leading cause of death for children ages 1 to 4 from March 1, 2020, to April 30, 2022, according to CDC data released on June 17.

The White House said vaccinations for children under age 5 would begin on Tuesday after the Juneteenth federal holiday.

The Biden administration has procured a significant supply of vaccines for this age group, with 10 million doses available initially and millions more available in the coming weeks, according to a plan released by the White House.

Parents will be able to get their youngest children vaccinated at their pediatricians' offices, as well as at pop-up clinics at children's museums, libraries and child-care sites, according to the plan.

Ashish Jha, who oversees the Biden administration's COVID-19 response, said that appointment availability might be limited initially but every parent who wants to get their child vaccinated should be able to do so in the next few weeks. 

(With input from Xinhua)