(CNN) The Moderna and Pfizer/BioNTech Covid-19 vaccines are now authorized for emergency use in young children. The US Food and Drug Administration expanded the authorizations for the vaccines Friday to include children as young as 6 months.
However, shots can't be given until the US Centers for Disease Control and Prevention's vaccine advisers have voted on whether to recommend them -- a vote is scheduled for Saturday -- and CDC Director Dr. Rochelle Walensky has signed off on that recommendation. The White House has said vaccinations for younger children may begin next week.
Moderna's vaccine is now authorized for use in children 6 months through 17 years and Pfizer/BioNTech's for children 6 months through 4 years. About 17 million kids under the age of 5 are now are eligible for Covid-19 vaccines.
"Many parents, caregivers and clinicians have been waiting for a vaccine for younger children and this action will help protect those down to 6 months of age. As we have seen with older age groups, we expect that the vaccines for younger children will provide protection from the most severe outcomes of COVID-19, such as hospitalization and death," FDA Commissioner Dr. Robert M. Califf said in a news release. "Those trusted with the care of children can have confidence in the safety and effectiveness of these COVID-19 vaccines and can be assured that the agency was thorough in its evaluation of the data."
Previously, the Pfizer/BioNTech vaccine was authorized for people 5 and older and approved for 16 and up, and Moderna's vaccine was authorized only for adults.
Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research, called Covid-19 vaccines for younger age groups a "milestone."
"It is a bit of a milestone to bring down the age range for these vaccines as we work through this," Marks said Wednesday in a meeting of the FDA's Vaccines and Related Biological Products Advisory Committee.
In that meeting, the committee members voted unanimously in favor of expanding the authorizations to include children as young as 6 months.
"To be able to vote for authorization of two vaccines that will protect children down to 6 months of age against this deadly disease is a very important thing," said committee member Dr. Archana Chatterjee, dean of the Chicago Medical School at Rosalind Franklin University.
She compared the day to December 2020, when the first Covid-19 vaccines were authorized for adults and older teens.
"I'm really pleased that we've reached this kind of milestone," said committee member Dr. Ofer Levy, of the Precision Vaccines Program at Boston Children's Hospital, who also likened the moment to when Covid-19 vaccines previously were authorized for other age groups.
"I recall our first vote a year ago or more on the first Pfizer authorization," Levy said. "I was one of the 17 votes in favor. I remember those early discussions -- even then, should the 16- and 17-year-olds be included? At that point, that was a controversial topic that was being discussed. And here we are now, as a committee unanimously recommending authorization down to 6 months of age. So we've come a long way."
Many public health experts worry that even though the Covid-19 vaccines are now authorized for younger age groups, parents of these children might not take their kids to receive the vaccinations.
There is already slow uptake of Covid-19 vaccines among children in the United States.
"Having vaccine options for the youngest children is very important; however, we have seen a relatively low uptake of Covid vaccines in children in the 5- to 12-year-old group, and so my concern is that uptake in the youngest children under 5 years old might also be lower than we would like," Dr. Dan Barouch, director of the Center for Virology and Vaccine Research at Beth Israel Deaconess Medical Center in Boston, told CNN on Wednesday.
Barouch, who is not involved in the FDA's decision, helped develop and study the Johnson & Johnson Covid-19 vaccine.
He said there were "striking" differences in how many adults are fully vaccinated compared with children and teens.
Children 5 to 11 were the most recent group to become eligible for vaccination, in November. But just 29% of these children are fully vaccinated with their two-dose primary series in the United States, according to the CDC, compared with about:
"We are planning and preparing for the rollout of pediatric vaccines. Of course, there's a lot of work to be done to look at uptake of this vaccine. Some of the polls and surveys that have gone out to the public have indicated an ongoing lessening of parents considering giving their children these vaccines over time," said Lori Tremmel Freeman, chief executive officer of the National Association of County and City Health Officials.
According to a Kaiser Family Foundation's Vaccine Monitor survey, published in May, only 18% of parents of children under 5 said they would vaccinate their child against Covid-19 as soon as a vaccine was available.
"I think the more the pandemic is in the rearview mirror for some people -- or they believe it is -- then the less compelled they will be to do this, and so we have a big public health education campaign ahead of us," Freeman said. "Also, health departments at the local level will be looking to understand the landscape of their community in terms of how many providers, pediatricians and pharmacies have actually signed up to give out the vaccine."
Under the FDA's authorization, the Moderna vaccine can be given as a two-dose primary series, at 25 micrograms each dose, to infants and children 6 months through 5 years of age. For older children, ages 6 to 11, the doses are administered at 50 micrograms.
The Pfizer/BioNTech vaccine now can be given as a three-dose primary series, at 3 micrograms each dose, for use in infants and children 6 months through 4 years.
The FDA's vaccine advisers have determined that the benefits of both vaccines outweigh the risks and that the vaccines have been "well-tolerated" among the children who received them in clinical trials.
"The benefits seem to clearly outweigh the risks, particularly for those with young children who may be in kindergarten or in collective child care," committee member Oveta Fuller, an associate professor of microbiology and immunology at the University of Michigan Medical School, said of the Moderna vaccine.
Committee member Dr. Art Reingold added that even though the risk of Covid-19 hospitalization and death is lower for young children than for adults, children already get vaccinations to protect them against diseases for which their risk is low.
"If we have a vaccine whose benefits outweigh the risks, then making it available to people is a reasonable choice. I would point out that we as a country continue to give a large number of vaccines to children where the risk of the child dying or being hospitalized of those diseases are pretty close to zero," such as polio and measles, said Reingold, of the University of California, Berkeley.
The number of Covid-19 hospitalizations and deaths in children is concerning and much higher when compared with influenza-related deaths and hospitalizations, Marks said.
"There still was, during the Omicron wave, a relatively high rate of hospitalization during this period," he said. "That rate of hospitalization actually is quite troubling, and if we compare this to what we see in a terrible influenza season, it is worse."
Marks said the number of deaths for children 4 and under during the first two years of the pandemic "also compares quite terribly to what we've seen with influenza in the past."
"We are dealing with an issue where I think we have to be careful that we don't become numb to the number of pediatric deaths because of the overwhelming number of older deaths here. Every life is important," he said, adding that "vaccine-preventable deaths are ones we would like to try to do something about."
He added that the Covid-19 vaccines are an intervention similar to the influenza vaccine, which has been broadly and routinely used and accepted to prevent deaths in all ages.