Fully vaccinated people don’t need COVID-19 booster at this time, FDA, CDC say

With the spread of more transmissible variants of the coronavirus in the U.S., people who are fully vaccinated against COVID-19 do not currently need a booster shot, officials said. 

"Americans who have been fully vaccinated do not need a booster shot at this time," the Centers for Disease Control and Prevention and the Food and Drug Administration said in a joint statement late Thursday

The agencies added that those who are inoculated are protected from severe disease and death, including from the delta variant — which is spreading rapidly around the world and now accounts for most new U.S. infections.

The statement comes after Pfizer-BioNTech announced plans to seek FDA authorization for a booster dose of its COVID-19 vaccine in August. Pfizer’s Dr. Mikael Dolsten told the Associated Press that early data from the company's booster study suggests people’s antibody levels jump five- to 10-fold after a third dose, compared to their second dose months earlier.

Dolsten pointed to data from Britain and Israel showing the Pfizer vaccine "neutralizes the delta variant very well." But he said the assumption is that when antibodies drop low enough, the delta virus eventually could cause a mild infection before the immune system kicks back in.

The city of Long Beach's Department of Health & Human Services  hold an evening COVID-19 vaccination clinic Long Beach City College Pacific Coast Campus.

FILE -The city of Long Beach's Department of Health & Human Services holds an evening COVID-19 vaccination clinic Long Beach City College Pacific Coast Campus on July 6, 2021, in Long Beach, California. (Francine Orr / Los Angeles Times via Getty

FDA authorization for a potential booster dose would be just a first step and wouldn’t automatically mean Americans get offered the third shot. Public health authorities would have to decide if they’re really needed, especially since millions of people have no protection, according to Dr. William Schaffner, a vaccine expert at Vanderbilt University Medical Center.

"The vaccines were designed to keep us out of the hospital" and continue to do so despite the more contagious delta variant, Schaffner said. Giving another dose would be "a huge effort while we are at the moment striving to get people the first dose."

In the joint statement, the CDC and FDA echoed many public health officials in the urgent call to get vaccinated. 

"People who are not vaccinated remain at risk," the health agencies said. "Virtually all COVID-19 hospitalizations and deaths are among those who are unvaccinated. We encourage Americans who have not yet been vaccinated to get vaccinated as soon as possible to protect themselves and their community."

Currently, only about 48% of the total U.S. population is fully vaccinated — and some parts of the country have far lower immunization rates, places where the delta variant is surging. On Thursday, Dr. Rochelle Walensky, the CDC’s director, said that’s leading to "two truths" — highly immunized swaths of America are getting back to normal while hospitalizations are rising in other places.

"This rapid rise is troubling," she said: A few weeks ago the delta variant accounted for just over a quarter of new U.S. cases, but it now accounts for just over 50% — and in some places, such as parts of the Midwest, as much as 80%.

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This story was reported from Cincinnati. The Associated Press contributed.