Biden seeks more COVID-19 vaccine

President Joe Biden announced Tuesday that his administration is working to purchase an additional 200 million doses of the two COVID-19 vaccines, a move that could fully vaccinate the entire US population by the end of the summer.

The government intends to order 100 million more doses each from Moderna and Pfizer, the two drugmakers authorized for emergency use in the US. That is in addition to the 400 million combined doses the companies already had committed to providing to the US, Biden said.

"It will be enough to fully vaccinate 300 million Americans to beat the pandemic," Biden said.

The new purchases would increase total vaccine orders for the US by 50 percent, from 400 million to about 600 million shots, and those additional doses are expected to be delivered this summer, the White House said in a fact sheet.

The announcement comes after several states have reported vaccine and supply shortages while tens of thousands of people who managed to get appointments for a first dose have complained of cancellations.

Biden outlined the new purchase along with a plan to temporarily speed up shipments to states from 8.6 million doses to about 10 million doses a week.

Delivering a minimum 10 million doses to states means a 16 percent increase from the current weekly rate. Although the higher pace may only last three weeks, it's not clear where the new doses are coming from.

The Health and Human Services department is also planning to increase vaccine doses going to states, tribes and territories over the next three weeks instead of the previous one-week look-ahead. It will let states know how many doses they will be receiving at least three weeks in advance.

"This increased transparency will give state and local leaders greater certainty around supply so that they can plan their vaccination efforts and administer vaccines effectively and efficiently," the White House said in the fact sheet.

The boost of 1.4 million weekly allocations will primarily come from Moderna.

Pfizer, which makes the second authorized vaccine, announced earlier Tuesday it was ahead of schedule on fulfilling the 200 million doses the US purchased last year.

Biden has promised to administer 100 million shots in his first 100 days in office. "I want to be clear — 100 million shots in 100 days is not the endpoint, it's just the start," Biden said Tuesday.

"I hope you're all asking me by the end of the summer that 'you have too much vaccine left over,' that 'you have too much equipment left over,'" he said. "That's not my worry. I hope that becomes a problem rather than we somehow find interruptions in supply of vaccines."

The US is administering about 1.3 million doses per day right now, according to an average compiled by the Bloomberg Vaccine Tracker. That includes Monday when 1.1 million shots were recorded.

Meanwhile, evidence from K-12 schools that reopened for in-person instruction in the fall has found little evidence that schools contributed significantly to the spread of COVID-19, according to a new article published Tuesday in JAMA, the journal of the American Medical Association.

The evidence indicates that in-person instruction can be carried out safely with precautions, and schools should reopen for in-person instruction as soon as possible, researchers from the Centers for Disease Control and Prevention said.