US to buy 200 million more doses of Pfizer vaccine, says White House

The federal government is buying 200 million more doses of the Pfizer coronavirus vaccine to prepare for future needs, such as boosters and shots for kids under 12.

White House Press Secretary Jen Psaki says the Biden administration wants to have maximum flexibility to address changing conditions, and it's going to prepare for every contingency.

The additional doses will be delivered between this fall and spring of next year.

It's unclear whether booster shots will be needed for fully vaccinated people, but breakthrough infections attributed to the rapidly spreading delta variant have sparked a discussion. Most new coronavirus cases in vaccinated people have been mild or asymptomatic.

Likewise, it is still unclear if coronavirus vaccines will be approved for younger children.