How many COVID-19 vaccine doses are in play now -- and what to expect next

As vaccine eligibility begins to open up nationwide, the United States is likely to head into April with at least 196 million Covid-19 vaccine doses delivered -- and the Biden administration may be on track to reach its goal of enough doses for every adult by the end of May.

A total of 27 million Covid-19 vaccine doses will be distributed across the United States this week, the White House said Wednesday.

As of Thursday morning, more than 169 million doses total of Covid-19 vaccine have been delivered nationwide so far, according to the US Centers for Disease Control and Prevention. Of that total, about 84 million doses are from Pfizer, 81 million from Moderna and 5 million from Johnson & Johnson.

"We will have 27 million doses allocated across all distribution channels this week. Two-thirds of the 27 million doses will be going to states and jurisdictions for them to distribute to distribution sites," Andy Slavitt, the White House's senior adviser for Covid-19 response, said during a briefing on Wednesday.

So far about a third of US adults -- around 84 million -- have received at least one vaccination dose.

In February, Pfizer and Moderna pledged to make a combined total of 220 million doses available for shipment by the end of March and Johnson & Johnson pledged to make its 20 million doses available in the same time frame.

Johnson & Johnson told CNN on Wednesday it's still on track to deliver a total of 20 million doses by the end of March and Pfizer appears to be on track to have 120 million released and ready for shipment on March 31. CNN also reached out to Moderna for comment.

However, officials in President Joe Biden's administration told CNN they are not confident that Johnson & Johnson will meet its self-imposed deadline to deliver 20 million coronavirus vaccines by the end of March, despite optimistic statements from the company.

Administration officials, who spoke on the condition of anonymity in order to comment on internal discussions, said they aren't willing to guarantee those millions will be ready within the next week. They're hopeful, but not positive, because the delivery schedule has not accelerated in the way officials had hoped, one told CNN.

Here is a breakdown of how many doses to expect, where and when.

Health departments and pharmacies

US health departments can expect to see more than 18 million doses per week of Covid-19 vaccine through the end of March, Lori Tremmel Freeman, chief executive officer of the National Association of County and City Health Officials, told CNN on Wednesday.

About 16 million of those doses are expected to come from Pfizer/BioNTech and Moderna, and about 2 million from Johnson & Johnson.

"The White House is also expecting a one-time added allocation of 2.1 million Pfizer doses," Freeman said, referring to numbers that the White House shared with state and local health officials in a meeting on Tuesday.

As for pharmacies, Freeman said 2.8 million doses of the Pfizer and Moderna vaccines are expected to continue being delivered at existing levels to pharmacies but will benefit from a one-time additional expansion of 1 million Pfizer doses over the next three weeks, as well.

Shipments of Johnson & Johnson's vaccine to pharmacies will also boost the federal pharmacy program allocations by as many as 1.5 million doses, Freeman said.

Vaccines will continue to be distributed to federally qualified health centers and the number of facilities receiving allocations will increase to 950 sites in the weeks ahead, but Freeman said she did not have exact numbers of doses allocated to these centers.

Freeman said the trajectory of vaccine availability has been on track and it is expected that vaccine supplies "will continue to rapidly scale even further" in April to 22 to 24 million doses per week to health departments alone.

Johnson & Johnson spokesperson Lisa Cannellos told CNN in an email on Wednesday that the company still expects "to deliver 20 million single-shot vaccines by the end of March."

Pfizer spokesperson Jerica Pitts told CNN the company still expects to deliver 300 million doses of its Pfizer/BioNTech Covid-19 vaccine to the US government by the end of July, "enabling the vaccination of up to 150 million Americans."

Enough for every adult by end of May: 'It's possible'

Biden said earlier this month that the United States will have enough Covid-19 vaccine supply for every adult by the end of May.

If the nation continues a pace of 27 million doses per week for the next nine weeks, that means about 243 million doses would have to be distributed between now and May 26.

That number of 243 million, combined with the 164 million doses already delivered, as of Wednesday, add up to enough doses to at least vaccinate about 203 million adults with a two-dose regimen of the Pfizer/BioNTech or Moderna vaccine. Johnson & Johnson's vaccine requires just one dose.

There are about 330 million people in the United States, of whom an estimated 22% are under 18. That would make for 257 million adults. Assuming that some adults will be vaccinated with a single dose of the Johnson & Johnson vaccine, the United States appears to be on track to reach President Biden's goal of having enough doses for every US adult.

So far, "there are now a total of 84 million people who have received at least one vaccination dose, or one in three adults, and 45 million people who've been fully vaccinated -- that's better than one in six adults," Slavitt said on Wednesday.

"Importantly, today we cross a milestone: 70% of Americans age 65 and over have now received at least one shot. This is a long way from seven weeks ago, when only 8% of seniors had received a single shot."

On the local level, the Biden administration appears on track to reach its goal of having enough Covid-19 vaccine for every adult by the end of May, Freeman said.

"I think it's possible," she said.

About 25% of the total US population already has received at least one dose of Covid-19 vaccine, "which is a pretty amazing milestone," Freeman said.

"We don't really have any reason to believe that production will decline at this point. We might have a little week or two here where things are ramping up, but certainly in April we should see vaccine becoming much more available," Freeman said.

"Therefore, you should see some rapidly increasing expansions of vaccine appointments in communities across the country, beyond those initial priority groups and into populations that are more general," Freeman said. "So I think definitely by within the next four to six weeks we'll be into the general population."

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