WASHINGTON — With a stockpile of at least 100 million doses at the ready, Biden administration officials are developing a plan to start offering coronavirus booster shots to some Americans as early as this fall even as researchers continue to hotly debate whether extra shots are needed, according to people familiar with the effort.
The first boosters are likely to go to nursing home residents and health care workers, followed by other older people who were near the front of the line when vaccinations began late last year. Officials envision giving people the same vaccine they originally received. They have discussed starting the effort in October but have not settled on a timetable.
While many outside experts argue there is no proof yet that the vaccines’ protection against severe disease and hospitalization is waning in the United States, administration officials say they cannot afford to put off figuring out the logistics of providing boosters to millions of people until that tipping point is reached. The spotty nature of the nation’s disease-reporting network makes the question of timing even trickier.
The effort comes as yet another wave of the coronavirus grips the nation, reversing much of the progress the administration had made. Hospitals in states like Texas, Louisiana and Mississippi are again swamped with patients, the vast majority of them unvaccinated.
the European Union said this month that there was not yet enough data to justify boosters. Germany and France nevertheless have announced plans to start giving booster shots to the older adults and other vulnerable populations next month.
Israel, which is already administering booster shots to people over 60, announced on Thursday that it would offer them to those over 50 as well. Britain so far is holding off, but already has a detailed plan for distributing boosters to people 50 and over.
the C.D.C. recommended them. The authorities decided those individuals, who make up fewer than 3 percent of Americans, merited extra shots because many fail to respond to the standard dosage.
Administration officials continued to insist this week that boosters remained unnecessary for the general population for now. Determining at what point that changes is difficult because administration experts lack up-to-date data on so-called breakthrough infections in vaccinated people, including their prevalence, when such people were vaccinated and which vaccine they received.
Instead, officials are analyzing a complex array of information from a range of sources, including from the vaccine manufacturers Moderna and Pfizer-BioNTech, which has an agreement with the Israeli government to review its data. Other sources of information include a variety of foreign governments, and the Centers for Disease Control and Prevention, which collects data from states and hospitals. All of that data is subject to interpretation and can be marshaled to support arguments for or against boosters.
“It’s somewhat chaotic, with everybody doing their own thing,” said Dr. Jesse L. Goodman, a former chief scientist at the F.D.A. and now a medical professor at Georgetown University. “We need a system to monitor real-world vaccine effectiveness in near-real-world time.”
He added: “When something comes up like the Pfizer report on Israel, we should be able to say, ‘Are we seeing that here?’ I’m very distressed that we’re not there yet.”