The White Home estimated on Wednesday that nearly a million young children have gotten Covid-19 shots for the reason that Pfizer-BioNTech vaccine was cleared for 5- to 11-year-olds final week — a determine that President Biden’s high coronavirus adviser, Jeff Zients, described as a “good begin.”

Due to a lag in reporting to the Facilities for Illness Management and Prevention, which gathers vaccination data, the White Home did its personal evaluation by amassing data from pharmacies and state and native well being officers, Mr. Zients mentioned. He mentioned officers “estimate conservatively” that 900,000 kids have had their first shot.

He mentioned an extra 700,000 pediatric vaccination appointments have been scheduled at pharmacies throughout the nation.

“Our purpose clearly is to vaccinate as many youngsters as attainable,” Mr. Zients mentioned at a White Home briefing on the pandemic. “That is the very starting of this system. This system is simply getting as much as full power.”

The vaccine is now obtainable to roughly 28 million kids nationwide and to this point, it has been troublesome to gauge father or mother curiosity. In northwest Washington D.C., a comparatively prosperous space, there have been lengthy strains of oldsters and kids ready to be vaccinated over the weekend.

An elementary faculty in Virginia visited by Jill Biden, the primary woman, earlier this week quickly filled 260 vaccine appointments. The college has 355 college students.

And in New York City on Monday, officers had been caught off-guard by the demand at sure colleges, which far exceeded the curiosity final spring at school-based vaccine clinics for youngsters.

However elsewhere within the nation, many mother and father are cautious. A survey by the Kaiser Family Foundation, revealed final month earlier than the F.D.A.’s authorization for youthful kids, discovered that 27 p.c of oldsters mentioned they might “undoubtedly not” get their 5-to-11-year-olds vaccinated in opposition to the coronavirus. An extra 33 p.c mentioned they might “wait and see” how the vaccine was working earlier than getting their kids the photographs.

The marketing campaign to vaccinate younger kids doesn’t resemble the marketing campaign to vaccinate adults. There are not any mass vaccination facilities. The dose and the vials are smaller. The White Home is recruiting pediatricians to get entangled.

The marketing campaign additionally differs in a single different notable respect: The White Home has not publicly set a purpose for what number of kids it wish to see vaccinated and when.

Earlier this yr, Mr. Biden set a purpose of getting 70 p.c of all adults obtain at least one Covid-19 shot by July 4. The White Home did not meet that goal by that date, and when Mr. Zients was requested on Wednesday if the Biden administration had set a purpose for youngsters, he ducked the query.

“I wish to emphasize once more that now we have loads of provide for all 28 million youngsters ages 5 to 11,” Mr. Zients mentioned in reply to the query, including, “We’re off to a really robust begin.”