Will Americans get boosted?

Published over 1 year ago • 3 min read

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It’s telling just how much the news coverage of the new Covid-19 boosters has focused on the question: When should I get it? It reflects how much we’ve shifted toward an individualistic response to the pandemic. It reflects the reality that the readers of top US news sources are already vaccinated and are the people most likely to want to get boosted. And it reflects the fact that it’s easier to write about a question that has an answer: You should get the new booster, and the when depends mostly on how recently you’ve had Covid or gotten a shot.

It’s harder to write about a question that no one knows how to answer, like: Will the new boosters make any difference?

The sense among experts seems to be, roughly: They will help, but we’re not sure how much, and they won’t be a knockout blow. But getting more specific than that requires answering three other questions:

  1. How effective will the boosters prove to be in preventing infection and disease?
  2. How many people will get one?
  3. Will a new variant emerge that undermines the boosters’ effectiveness?

Three impossible-to-answer questions seems like too much for one email. So this week we’re tackling #2: How many Americans will get the new boosters?


In late August, the FDA authorized new “bivalent” booster shots that target both the original strain of Covid and two strains of Omicron—including the currently dominant BA.5 strain. They arrived in pharmacies last week.

There’s not enough human data to say confidently how well they’ll work. An experiment using mice showed a strong immune response and a human study of a different bivalent booster targeting a different strain (that’s moving forward in the UK) showed positive results, too. In effect, the improved targeting of this booster will tradeoff against the diminishing returns of exposure to the virus. (Read this to go deeper.)

Anyone 12 or older who received an initial vaccination at least two months ago is eligible. Pfizer’s version of the booster is approved for anyone older than 12; Moderna’s for anyone over 18. The CDC estimates a total of about 200 million people are eligible. As of this writing, 79% of Americans have received at least one vaccine dose and 33% have received at least one dose of the original-strain boosters from 2021.

But the bivalent booster rollout comes as many vaccination sites have closed and money for vaccination campaigns is drying up. Last year, according to the New York Times, states were promised $8.5 billion in FEMA reimbursements for vaccine spending; this year that figure is just $550 million. 60% of the remaining vaccination sites are pharmacies. The federal government has also run out of funds to reimburse providers for vaccinating the uninsured.


The Atlantic’s Katherine J. Wu on the administration’s mixed messaging

“The wind-down of Covid funding is making it much harder for people without insurance or other reliable health-care access to get boosted… People have been repeatedly told not to fear the virus or its potentially lethal threat… The US needs people to take this vaccine because it has nothing else. But its residents are unlikely to take it, because they’re not doing anything else.”

Eric Topol, a physician who writes on Substack, on last year’s lackluster booster push

“If the new booster campaign is seen as a ‘rush job’ and concerns are heightened that the data is based only from mice, that will certainly not enhance uptake. Framing this further, we have a serious booster lack of uptake in the United States, with only 32% of the population having had any booster shot. That compares quite poorly to our peer countries that are all at least double that rate. The messaging from CDC about boosters—which should be mission critical—was delayed from the get go in the Fall of 2021, and has never gotten on track.”

Dr. Burnestine Taylor, Alabama’s medical officer for disease control and prevention, just says it

“At this point, we’re not doing a hard push… It’s a personal decision.”


(For reference, the original boosters began rolling out at the end of the summer of 2021 and were authorized for all adults November 19, 2021.)


How likely is it that the US administers more than 20 million doses of Covid vaccine in September?

Note: This forecast, like the chart above, includes all vaccine doses—not just boosters.

What do you think?

Click the choice that best represents your forecast

~10% chance​ ​

~30% chance​ ​

~50% chance​

​~70% chance​ ​

~90% chance​

The fine print

This question will be resolved using numbers from OurWorldInData. You can explore the data here or download it here. The chart above sums a monthly total of “Vaccine doses”, “New per day”, for the US.


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