Gustave Perna, the four-star Army general overseeing the formidable task of distributing coronavirus vaccines, said Saturday he was responsible for the “miscommunication” with states causing them to receive vastly fewer doses of the Pfizer-BioNTech vaccine in the second wave of shipments next week than they had been anticipating.

“I want to assure everybody, and I want to take personal responsibility for the miscommunication,” Perna, who is chief operating officer for the Trump administration’s Operation Warp Speed, told reporters. “I know that’s not done much these days, but I am responsible.”

The problem stemmed from mistaken forecasts he initially gave state officials, which did not account for steps involved in actually clearing available vaccine for release, he said. “There is a delay between what is available and what is releasable,” he said, “because we’re talking about hundreds and thousands and millions of doses that we want to make sure are right.”

But he was not clear about the scope of quality assurance, or about why it would delay the release of doses, saying only that the Food and Drug Administration “does a fantastic job doing that.”

The FDA does not review batches of vaccine before their distribution, an agency spokesperson said Saturday in response to requests to explain the process. Under the terms of the agency’s authorization for the Pfizer-BioNTech vaccine, the company is required to submit “certificates of analysis for each drug product lot at least 48 hours before vaccine distribution.” But the FDA does not review the information before the product is shipped.

FDA Commissioner Stephen Hahn confirmed that later in a tweet, saying, “they can distribute without waiting for FDA’s ok.”

Asked about the steps involved in clearing doses for release, Perna said he didn’t know “the exact details on that.” He did stress that there had been “zero problems” with Pfizer’s product.

The confusion about the size of shipments was compounded by the move to notify states earlier — on Tuesday rather than Friday — of the number of doses on hand for them to order for the following week, Perna said. Before that notification, states were operating based on a “forecast worksheet that laid out what we thought might be possible in eventual distribution,” he said.

Asked to explain in simpler terms what happens to make doses releasable, he said, “I am not going to spend any more time talking about the details between fill-finish and releasable.”

Dec. 16 was a day of relief at Temple University Hospital in Philadelphia. Health-care workers lined up and some even teared up when they received a vaccine. (The Washington Post)

The on-camera explanation came two days after reports of widespread confusion in the states yielded conflicting explanations from the Trump administration and from Pfizer, which are locked in negotiations over additional vaccine doses for the United States. A Health and Human Services spokesman initially denied any changes to state allocations, while questions about Pfizer’s manufacturing capacity prompted the pharmaceutical giant to put out a statement saying it faced no production issues and had millions of unclaimed doses.

“We have millions more doses sitting in our warehouse but, as of now, we have not received any shipment instructions for additional doses,” the statement read.

Across the country, governors and top health officials said their expected supply for next week had been cut without explanation by as much as 40 or 50 percent, forcing them to change their plans. Already, they were making agonizing decisions about how to allocate a sharply limited share of shots, choosing between ICU nurses and respiratory therapists and emergency medicine residents. Some states had been intending to use the second shipment to begin vaccinating residents of long-term-care facilities, where nearly 40 percent of covid-19 deaths have occurred.

The faulty forecasts described by Perna were part of planning assumptions that had been built into Tiberius, a data system developed with Palantir, the Denver-based software company. The assumptions shared with states using that system were not updated, according to a federal health official who spoke on the condition of anonymity to share internal discussions. States have reported varying levels of comfort with the brand-new data system.

“Everyone assumed that was the final count,” the federal official said. When it came time to order doses in a separate system operated by the Centers for Disease Control and Prevention, state officials found there were fewer doses available.

That led to confusion because state officials were not immediately given an explanation by the Trump administration. Perna said he has since had conversations with numerous state officials, including Washington Gov. Jay Inslee (D).

An added layer of complexity, Perna noted, was the need to have certainty about the availability of a second dose for each initial shot dispatched by the federal government. The Trump administration has opted to hold back booster shots to be delivered 21 days later in the case of the Pfizer-BioNTech vaccine, rather than sending out all doses for states and other jurisdictions to divide into first and second shots. The decision has baffled people close to Pfizer and surprised some state officials, who said it made their planning more difficult.

Still, state officials said they were rolling with the punches amid a CDC advisory panel report that 272,001 doses of the Pfizer-BioNTech vaccine had been administered as of Saturday morning.

“When we get projections from the federal government, we use those but also know it could change,” said Jinlene Chan, Maryland’s acting deputy health secretary.

The FDA’s Friday night authorization of Moderna’s two-dose regimen for emergency use also means more doses will be available and scheduled for delivery across the United States as soon as Monday. Between Pfizer and Moderna, 7.9 million doses of vaccine will be shipped next week to 3,700 locations, Perna said.

Perna expressed confidence the country will have 20 million doses of coronavirus vaccine allocated by month’s end, but said distribution of some of those doses could extend into the first week of January. The estimate left room for the government to fall short of its projection that 20 million people could be inoculated by year’s end.