Health and Science

More Americans are getting Covid vaccine boosters than first doses in rush for third shots

Key Points
  • The U.S. is reporting an average of about 362,000 boosters administered per day over the past week, 57% higher than the 231,000 average daily first doses.
  • About 8.9 million boosters overall have been administered as of Wednesday, covering 4.7% of all fully vaccinated Americans and more than 12% of the immunized 65 and older population. 
  • A key FDA advisory panel meets Thursday and Friday to discuss the efficacy and safety of extra doses of the Moderna and J&J vaccines.
Germaine T. Leftwich, 67, receives a Pfizer covid-19 vaccine booster shot from Dr. Tiffany Taliaferro at the Safeway on Capitol Hill in Washington, D.C., on Monday, October 4, 2021.
Tom Williams | CQ-Roll Call, Inc. | Getty Images

More Americans are getting third Covid shots than first vaccine doses as people who completed their two-dose regimen of Pfizer or Moderna's shots six or more months ago are now eligible and lining up for an extra jab. 

An average of 362,000 people a day got boosters over the past week, about 57% more than the 231,000 people per day who started their first doses, according to data from the Centers for Disease Control and Prevention.

"It's kind of reminiscent of those early days when over-65 qualified in a priority group and we saw people flooding websites and pharmacies and clinics," Dr. Kavita Patel, a primary care physician in Washington who worked on health-care initiatives in the Obama administration, said about the high demand for boosters on CNBC's "Squawk Box" on Tuesday. 

U.S. regulators authorized booster shots of Pfizer and BioNTech's vaccine to a wide array of Americans in late September, including the elderly, adults with underlying medical conditions and those who work or live in high-risk settings like health and grocery workers. The move made roughly 60 million Americans eligible for a third shot, President Joe Biden said in an address following the CDC's endorsement.

About 8.9 million boosters overall have been administered as of Wednesday, CDC data shows, covering 4.7% of all fully vaccinated Americans and more than 12% of the immunized 65 and older population. 

"Those that are coming in and getting the booster vaccine are very comfortable with the vaccine, understand the benefit and have seen the benefit," said Dr. Annamaria Macaluso Davidson, who practices at Memorial Hermann Medical System, a group of 17 hospitals in Houston.

A surge in cases this summer driven by the highly contagious delta variant is convincing some people to get the vaccine for the first time, she said. "Those that are just coming in and starting, they would have had hesitancies for different reasons, and maybe finally consulted with a physician to understand that getting the vaccine outweighs any risk, and far outweighs the risk of getting Covid," she said.

The rush for additional doses among fully vaccinated people highlights the divide between the vaccinated and unvaccinated, according to Rupali Limaye, a faculty member at the Johns Hopkins Bloomberg School of Public Health. Limaye studies vaccine decision making and has been working with state health departments during the vaccine rollout. 

Because many of those getting third doses are the same people who were most eager to get shots earlier this year, boosters will give those people even stronger protection while the unvaccinated remain largely unprotected and at a substantially higher risk of hospitalization or death if they get Covid.

"We want to spread protection throughout a community," Limaye said. "We will have a portion of the population that will be well protected, and a proportion of the population that has had zero shots."

A Kaiser Family Foundation survey released last month showed that the emergency approval of Pfizer's booster shots for some people has done little to improve the split in attitudes on Covid-19 vaccines.

Among those surveyed, nearly 80% of the people who were vaccinated said news of the third doses shows that scientists are trying to make the shots more effective, but 71% of the unvaccinated said boosters are proof that the vaccines don't work.

Limaye said this misunderstanding about third doses echoes conversations happening at town halls and community groups across the country. Because U.S. health officials weren't clear enough up front that boosters are an expected part of an immunization process, it has raised questions about why another shot is needed.

"We need to do a better job, in my opinion, saying that this is just how it is like any other virus," Limaye said, "and that we have to get boosters because immunity wanes over time."

Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention (CDC), and top infectious disease expert Dr. Anthony Fauci, testify before the Senate Health, Education, Labor, and Pensions Committee on Capitol hill in Washington, D.C., July 20, 2021.
J. Scott Applewhite | Pool | Reuters

Dr. Aaron Clark, a family medicine physician at The Ohio State University's Wexner Medical Center in Columbus, Ohio, said the interest he sees in boosters "far outweighs the demand for first shots."

Average daily Covid cases in the U.S. fell below 100,000 last week as the pandemic shows signs of easing, according to data compiled by Johns Hopkins University, with more than 56% of the U.S. population fully vaccinated. Still, while down from recent peaks, the country is reporting an average of more than 1,600 daily Covid deaths.

U.S. officials have repeatedly said that the vast majority of those currently hospitalized and dying because of Covid are unvaccinated.

A key Food and Drug Administration advisory panel will meet on Thursday and Friday to discuss the efficacy and safety of extra doses of the Moderna and Johnson & Johnson vaccines. Of the 188 million fully vaccinated Americans, 55% have received the Pfizer shots, 37% received Moderna, and 8% received a Johnson & Johnson shot, according to the CDC.

CNBC's Berkeley Lovelace Jr. contributed reporting.