US buys 200M more Pfizer vaccine doses, option for 'updated version'

The U.S. government has purchased an additional 200 million doses of the Pfizer-BioNTech COVID-19 vaccine and has the option for an "updated version" of the shot if needed, the companies announced Friday.

The doses are expected to be delivered between October 2021 through April 2022. With this recent purchase, the U.S. has now bought 500 million doses from Pfizer and its German partner BioNTech as the country looks to further increase its vaccine supply in case of the need for a potential booster shot.

This announcement is separate from an agreement announced last month, in which the companies will provide the U.S. with 500 million vaccine doses to donate to low-income countries around the world — where shots are far less plentiful.

About 110 million of the additional doses are expected to be delivered by the end of 2021, ad the remaining 90 million doses are to be delivered no later than April 30, 2022, the companies said.

The U.S. also has the option "to acquire an updated version of the vaccine to address potential variants as well as new formulations of the vaccine, if available and authorized," Pfizer-BioNTech said in a statement. 

In this photo illustration a vial of Pfizer BioNTech vaccine

FILE - A vial of Pfizer-BioNTech’s COVID-19 vaccine is pictured in a file image dated July 21, 2021. (Photo Illustration by Marcos del Mazo/LightRocket via Getty Images)

The possibility of booster shots has been a topic of discussion among U.S. health officials for months. Research from multiple countries shows the Pfizer shot and other widely used COVID-19 vaccines offer strong protection against the highly contagious delta variant, which is spreading rapidly around the world and now accounts for a majority of new U.S. infections.

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Pfizer has said booster shots could be needed within 12 months and plans to seek U.S. authorization for a third dose of its vaccine in August. But in response earlier this month, the U.S. Centers for Disease Control and Prevention and the Food and Drug Administration said that people who are fully vaccinated against COVID-19 do not currently need a booster shot.

The CDC considers someone fully vaccinated if they are two weeks after their second dose in a two-dose series, such as Pfizer or Moderna, or two weeks after their single dose of the Johnson & Johnson vaccine.

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Currently, only about 48.8% of the U.S. population is fully vaccinated. Some parts of the country have far lower immunization rates, and in many of those places, cases and hospitalizations are rising. 

CDC Director Dr. Rochelle Walensky called the latest surge "another pivotal moment" in the pandemic during a press briefing on Thursday, noting that some hospitals are reaching capacity in areas with low vaccination rates.

The delta variant, which was first detected earlier this year in India, now accounts for an estimated 83% of COVID-19 cases nationwide. The percentage is a dramatic increase from the week of July 3, when the highly transmissible variant accounted for about 50% of genetically sequenced cases.

Walensky urged unvaccinated Americans to get shots, saying, "We, together, are not out of the woods yet."

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This story was reported from Cincinnati.