(Both vaccines are two-dose regimens - Pfizer's second shot comes after 21 days and Moderna's second dose follows 28 days after the first.) But on Saturday, Perna said that although Warp Speed is on track to allocate 20 million doses to states by the end of December, the distribution of those doses will be pushed into early January. In his Saturday press conference,В Perna also made a slight tweak to Warp Speed's delivery goals for December.ДЇederal officials had previously said they were on track to give 20 million Americans their first shots before the year's end. Perna said the inflated estimates he gave states were a result of his own misunderstanding of the difference between doses manufactured and doses ready to be released. The recent confusion about states' supply estimates and timelines mainly stems from the complexity of the manufacturing process.Д®ven when vaccine doses are manufactured and ready to be shipped, they still need to meet quality-control requirements before being released. President Trump delivers remarks on Operation Warp Speed. Even with the number adjustments, Warp Speed will ship 7.9 million vaccine doses next week, with deliveries starting Monday at more than 3,700 sites across the country. The four-star general expressed confidence in the vaccination campaign overall, however. 'To the governors, to the governors' staffs, please accept my personal apology if this was disruptive in your decision-making and in your conversations with the people of your great state,' Perna said at a press conference. Supply estimates he previously gave to states for planning turned out to be incorrect, Perna said.

General Gustave Perna, Operation Warp Speed's chief operating officer, said the miscommunication was his fault. Over the past couple of days, more than two dozen states have said they are getting 30% or 40% fewer doses of Pfizer's COVID-19 shot next week than they were expecting.

Reporting from this episode is drawn from the new book.

The co-leader of the US government's coronavirus vaccine initiative claimed personal responsibility on Saturday for widespread confusion among state leaders about how many coronavirus vaccine doses they will receive. On today's episode, we look at the story behind the story of Operation Warp Speed and how the COVID-19 vaccines were made in record time.

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