The purchases increase available supply by 50 percent, bringing the total to 600 million doses. Because both products are two-dose regimens, that would be enough to fully vaccinate 300 million people. An estimated 260 million people in the United States are currently considered eligible to receive a coronavirus vaccine, though trials involving children as young as 12 could widen the pool.
Moderna issued a statement confirming the purchase and saying it was “working with its domestic manufacturing partners,” as well as federal regulators, to “explore ways to accelerate delivery, with the goal of providing this new order of 100 million doses before the end of July 2021.” A Pfizer spokeswoman did not immediately respond to a request for comment.
Moderna has already promised to supply the federal government with 100 million doses by the end of March and another 100 million by the end of June. Pfizer has indicated it can provide 120 million doses by the end of March and another 80 million by the end of May, two months earlier than its initial July target.
As the country seeks to stay ahead of the spread of the new variants, which are more transmissible and possibly more lethal, top health officials have expressed confidence that widespread inoculation will soon be possible because of a steady ramp-up in manufacturing.
“By the time we get to April, that will be what I would call, for better wording, ‘open season,’ namely, virtually everybody and anybody in any category could start to get vaccinated,” Anthony S. Fauci, the nation’s leading infectious disease expert, said Thursday on NBC’s “Today” show.
The Biden administration has already increased weekly allocations to states by nearly 30 percent, though shortages remain pronounced in many areas. Los Angeles Mayor Eric Garcetti said Wednesday the city would temporarily close a mass vaccination site at Dodger Stadium, along with several other locations, because there weren’t enough doses.
Additional doses are also expected to come from Johnson & Johnson, which submitted its application for a single-shot coronavirus vaccine to U.S. regulators earlier this month. If approved, the easy-to-store vaccine would further augment supply, though production setbacks are expected to limit availability until the spring. It’s also possible that vaccine experts may only recommend the vaccine for certain age groups.
Evidence from laboratory tests suggests the Pfizer and Moderna vaccines work against variants, but the ability of the immune response to block the South African variant is diminished. Another vaccine, developed by Novavax, was highly effective against the variant first discovered in Britain but far less so against the South African variant.
As more vaccine becomes available, new challenges, including staffing, will arise. But health officials say they’re preparing themselves.
“We’re strategizing around that now and the good thing is we’ve had a couple of months of experience doing this that we can learn from,” said Kevin Litten, a spokesman for the Louisiana Department of Health.
Carolyn Y. Johnson and Amy Goldstein contributed to this report.
