WASHINGTON — The White House on Thursday outlined the first steps in its plan to make coronavirus vaccines available this month for about 18 million children under age 5, if doses are authorized by federal regulators for the last group of Americans still eligible.

With the goal of the first vaccines being given the week of June 19, the Biden administration has already made 10 million doses available to states and health providers, with about 85% of children in that age group living within five miles of possible vaccination sites, according to White House estimates shared with reporters.

Half of the 10 million doses were made available for order last week, the other half this week, with an equal number of Pfizer-BioNTech and Moderna vaccines, the two that federal regulators are reviewing and could clear as early as this week. next.

“Let’s actually take a moment to realize how historic this is,” said Dr. Ashish K. Jha, President Biden’s coronavirus response coordinator. “It would mean that for the first time, virtually all Americans, from the oldest to the youngest, would be eligible for the protection afforded by vaccines.”

Health officials may face a complicated persuasion campaign in many parts of the country after an initial wave of vaccinations among impatient families who have waited far longer than families with older children.

Vaccine uptake in other age groups offers a daunting suggestion: just over a third of children aged 5 to 11 have received at least one dose of a vaccine, a number that some say Health experts, might predict even lower interest among parents of younger children.

State orders have been somewhat lukewarm so far, according to data senior administration officials provided to reporters during a Wednesday night briefing. Of the five million doses on offer last week, 58% of those made by Pfizer-BioNTech have been ordered, as have about a third of those made by Moderna.

The officials, who spoke on condition of anonymity to preview the official announcement on Thursday, said the initial orders were typical of Covid-19 vaccination campaigns so far, as states typically increase their orders over time. .

A Kaiser Family Foundation survey conducted in April found that only 18% of parents of children under 5 said they would get them vaccinated immediately, while 38% said they would wait and see. Their hesitation could be at least partly due to the fact that the virus is generally less risky for young children.

But Dr. Vivek H. Murthy, the surgeon general, said the risks were still significant. More than 30,000 children under the age of 5 have been hospitalized with the virus and nearly 500 have died, results which he says could be prevented by vaccination.

On Wednesday, new confirmed cases in the United States were roughly stable at around 110,000 a day on average for the past two weeks, according to a New York Times database, after falling from less than 30,000 there. a few months old. However, infections are believed to be vastly underestimated. The number of deaths has been volatile in recent weeks but remains below 400 per day on average.

“We are not done with the pandemic. The virus is still there,” Dr Murthy said. “We are still losing several hundred people a day to this virus.”

He has warned parents of a potential glut of misinformation targeting the shooting for young children, the subject of an advisory his office issued last year.

“Please ensure that the information you rely on comes from reliable sources such as your doctor, your local children’s hospital, your health department, medical associations like the American Academy of Pediatrics, the FDA and the CDC” , he said, referring to the Food and Drug Administration and the Centers for Disease Control and Prevention.

Dr. Jha said on Thursday that health officials expected many children under the age of 5 to be vaccinated by pediatricians and primary care physicians, unlike other age groups. But he and other officials said Thursday they had organized a network of other places that would work to get families vaccinated, including pharmacies and children’s hospitals.

To reach small pediatric practices and rural providers, the White House said Thursday, doses are packaged in the hundreds.

Government programs such as Medicaid, the Children’s Medicare Program, and the Women’s, Infants, and Children’s Program will work with families to encourage vaccination. Other groups, including the American Academy of Pediatrics, the Association of Children’s Museums and the National Diaper Bank Network, will provide educational materials.

Delivery of the vaccines depends on the FDA clearing the pediatric doses — a milestone that could happen as early as next week — and the CDC recommending them, which would officially kick off the campaign. The FDA and its outside panel of vaccine advisers are scheduled to meet Wednesday to discuss vaccines for young children; the CDC’s own expert committee is due to meet a few days later.

Dr. Rochelle P. Walensky, the director of the CDC, would be the last to sign.

Dr Jha said he expected vaccinations to start in earnest the following week, but suggested it might take time for some families to get access.

“In reality, that means we could see shots in the arms of children under 5 as early as the week of June 20,” he said of the federal exam schedule, adding that the June 16 federal holiday would mean that many offices would begin administering the firing on Tuesday, June 21.

“The vaccination program will intensify in the days and weeks that follow with more and more doses and more and more appointments available,” he said.

Moderna is seeking authorization for its two-dose vaccine for children under 6, while Pfizer is asking regulators to authorize its three-dose vaccine for children under 5.

Federal officials have said they are not preempting regulatory action by announcing plans to distribute the vaccine before it is authorized. Instead, they said, they are working to prepare families and doctors for a possible deployment. Last year, the White House was criticized for reversing the regulatory review that usually precedes vaccination campaigns when it announced a sweeping recall campaign before FDA officials or their outside advisers intervened. a decision that proved divisive.

Vaccine deliberations for younger children are not expected to provoke the same kind of dissent. Parents were briefly given hope over the winter when FDA officials worked to make two initial doses of Pfizer-BioNTech’s vaccine available to children while they studied a third dose. This plan backfired when data showed that two doses did not offer significant protection against the Omicron variant.

Moderna offers a two-dose regimen for children 6 months to 5 years old, using a quarter of an adult dose. Pfizer and BioNTech are working on a three-dose regimen for children 6 months to 4 years old, at one-tenth the adult dose.

Sarah Cahalan contributed reporting from Chicago.