Even in normal times, mass-vaccination campaigns involve many moving parts within a vast network of suppliers, transporters and middlemen.
The particulars of Pfizer’s vaccine will make this effort even more complex. The vaccine, developed with the German company BioNTech, has to be stored at around minus 70 degrees Celsius (minus 94 Fahrenheit) until shortly before it is injected. That is about the temperature of the South Pole on a winter day and colder than any of the other leading vaccines in development.
Pending results from other front-runners in the vaccine race could change the stakes. Moderna Therapeutics said on Wednesday that it had seen enough Covid-19 cases in its late-stage study to do an early analysis of its vaccine, which uses the same “messenger RNA” technology that Pfizer’s does. The technology has never produced an approved vaccine.
Nine other candidates are also in the final stage of testing. If any of those win approval from the F.D.A., that will reduce the importance of Pfizer’s vaccine but also introduce new questions, such as which hospitals and people get the different vaccines.
For now, though, Pfizer is in the spotlight.
If an analysis planned for next week confirms the vaccine’s safety, the company is likely to ask the F.D.A. this month for emergency authorization to distribute its vaccine. In that case, limited doses will most likely be shipped to large hospitals and pharmacies to be provided to health care workers and other vulnerable groups.
But the specifics of how that will work are hazy at best.
Pfizer does not yet know where the government wants the vaccine sent or who will be first in line to receive it, said Ms. Alcorn, the supply-chain executive.
“We’re working very closely, in the U.S., in particular, with Operation Warp Speed to identify those distribution points,” Ms. Alcorn said, referring to the federal initiative to produce and distribute Covid-19 vaccines. “We don’t have them today.”