“Make no mistake, distribution has begun,” Mr Perna said at a Saturday press briefing.
The shipments began after federal authorities on Friday authorized the Pfizer/BioNTech SE vaccine for emergency use. The initial wave of vaccines will go to 636 different locations across America which states and territories selected.
“We expect 145 sites across all the states to receive vaccine on Monday, another 425 sites on Tuesday, and the final 66 sites on Wednesday, which will complete the initial delivery of the Pfizer orders,” Mr Perna added.
Pfizer has been churning out doses at its massive Michigan plant for use in Europe and eventual distribution in the US ahead of the announcement. Canada and the UK have already authorized the Pfizer vaccine for widespread use.
In the US, health workers and residents of long-term care facilities will get priority access.
General Perna estimated that within three weeks, all designated vaccine distributors could begin getting shipments, and that by the end of the year there will be enough ready to vaccinate 20 million people.
Another leading vaccine candidate, from Moderna, is expected to get emergency authorization soon.