States, big cities and U.S. territories are among the 64 federally designated places that will receive the vaccines and decide when and where they will be administered. Government officials said Saturday they expect the initial doses to arrive at 145 sites on Monday. It will be up to the states not to mismanage the complex task of making sure the right number of doses get to the right places at the right times.

When Minnesota gets the 46,800 initial doses it expects in the coming week, they will be split between health-care workers and residents and employees of long-term care facilities. At first, they will go to 25 hospitals or large pharmacies capable of handling ultracold storage. Those places will use some and distribute the rest to 118 other locations.

New Mexico will send some of its initial 17,550 doses to five major hospitals that can handle ultracold storage, for distribution to health-care workers. A state health-department warehouse in Albuquerque will get the rest of the doses, break them up into truck shipments and send them to 32 other sites, where they must be administered within five days.

Kentucky has said it would distribute most of its 38,000 initial doses to long-term care facilities through CVS Health Corp. and Walgreens Boots Alliance Inc., which have federal contracts for that job. The other 12,000 doses will go to health-care workers.

Hospitals

Once hospitals get their doses, they need to make sure the vaccines don't spoil before they go into people's arms, and that none go to waste.

Before the U.S. Food and Drug Administration authorized the vaccine on Friday, hospitals performed vaccination dry runs, checked backup power and temperature settings for freezers and rushed to decide who would get shots first.

To choreograph the vaccine's arrival, hospitals have put employees on notice about the deliveries. Some staffers have hunted down photos of packaging to minimize the risk that boxes could be left unattended on loading docks, said Jessica Daley, a pharmacist and executive with Premier Inc., which contracts with pharmaceutical and other medical-supply manufacturers on behalf of hospitals.

"Everyone is very focused on ensuring that receipt of these products goes perfectly according to plan," she said.

At Mass General Brigham, a pharmacist likely will be notified by courier of the vaccine's arrival, said Paul Biddinger, the Boston-based hospital system's medical director for emergency preparedness. Mass General Brigham will store its allotment in a central location before distributing it to a dozen sites, using bar codes to track deliveries.

There are exacting procedures for retrieving the vials for vaccinations. Pfizer's containers can be opened only twice a day, and can't stay open for more than three minutes at a time, Dr. Daley said. Smaller boxes with trays of vials can be opened for no more than three minutes, and they can't be outside ultracold temperatures more than once every two hours.

People getting vaccinated must be moved through the line at a steady clip so the doses don't go bad. Hospitals must stagger appointments to avoid crowding, and keep those waiting socially distanced. A missed appointment could leave hospitals with unused doses that must be thrown out, said Dr. Biddinger. "We really don't want to waste any single dose, " he said.

Long-term care

Long-term care facilities are expected to get most of their vaccines through CVS and Walgreens, though some also will use smaller pharmacies. Each chain said it expects to receive supplies via FedEx or UPS in around 1,000 hubs, nearly all at pharmacies.

From those hubs, teams of pharmacists and other staffers will fan out to long-term care facilities, with some taking doses in small refrigerated totes. Walgreens said it is supplying about 30,000 facilities, and CVS is working with more than 40,000, so far.

"We just press 'go' and start running," said Rina Shah, Walgreens vice president for pharmacy operations and services.

Pharmacies also are preparing for Covid-19 vaccines besides Pfizer's, including one from Moderna Inc. that is under consideration for emergency authorization and could be cleared by the FDA this month.

Brad Phillips, director of operations for long-term care at Thrifty White Pharmacy, a regional chain based in Plymouth, Minn., that is supplying the vaccine to 240 facilities in North Dakota and Minnesota, said he expects to arrive at the company's headquarters pharmacy around 6 a.m. on Dec. 28, the designated start of the long-term-care rollout in Minnesota.

If it is authorized, he and about a half-dozen colleagues will head to a nursing home in the Minneapolis area in a company van with coolers of the Moderna vaccine. There, he said, he will don a gown, mask and gloves and enter the rooms of residents to inject them.

After weeks of planning, Mr. Phillips said, he is excited to start. "As we look at the impact on people and the health-care system," he said, "it is the biggest and most important thing I've been involved with."

--Melanie Evans, Paul Ziobro, Joe Barrett, Doug Cameron, Jennifer Smith and Alison Sider contributed to this article.

Write to Sarah Krouse at sarah.krouse@wsj.com, Jared S. Hopkins at jared.hopkins@wsj.com and Anna Wilde Mathews at anna.mathews@wsj.com

Corrections and Amplifications

This article was corrected on Dec. 21, 2020 because the last name of reporter Alison Sider was misspelled as Slider in the contributions line.

(END) Dow Jones Newswires

12-13-20 1103ET