Walgreens began administering the Pfizer/BioNTech COVID-19 vaccine to residents and staff at long-term care facilities in the United States on Friday.

It's the first time the U.S. pharmacy chain is offering vaccines in such facilities, like nursing homes.

Walgreens pharmacy teams members are currently providing the Pfizer/BioNTech vaccine at just 10 facilities in Connecticut, Ohio and Florida, including many in rural and urban medically-underserved areas. But the company will soon expand the vaccinations nationwide as more states finalize their distribution plans and receive vaccine allocations, according to Dr. Kevin Ban, Walgreens' chief medical officer.

"Next week, we'll be in 12 states in over 800 clinics. We're moving and ramping up to 35,000 clinics across the entire country, we're going to vaccinate more than 3 million people in these long-term care facilities," Ban told ABC News' Cecilia Vega in an interview Friday on "Good Morning America."

Ban said only people who are eligible to receive the COVID-19 vaccine under their state's Phase 1 distribution plan can get it. But once states move into Phase 2, residents and staff at long-term care facilities that have selected Walgreens as their vaccine provider will be able to make an appointment in advance.

"We're in the middle of a pandemic," he said, "and we don't want people all coming at once."

The U.S. Food and Drug Administration could grant emergency-use authorization for Moderna's COVID-19 vaccine "as soon as today," Secretary of Health and Human Services Alex Azar said Friday.

"The FDA has communicated to Moderna that we expect to grant their emergency-use authorisation. That could come as soon as today," Azar told ABC News chief anchor George Stephanopoulos in an interview Friday on "Good Morning America."

If the FDA does give the green light Friday, Azar said "trucks will roll, planes will fly this weekend," with "5.9 million doses of Moderna vaccine allocated for next week."

"This is an exceptionally safe vaccine," he said, "it's a shockingly effective vaccine -- the Moderna vaccine as well as the Pfizer vaccine."

Some 20 million doses of COVID-19 vaccines will be available across the United States for the month of December, according to Azar, who urged people to get the shot.

"All of us have complete confidence in the independence and quality of the FDA’s review process," he said. "That's why you're seeing the vice president, the second lady, the surgeon general today getting vaccinated."

Azar said a number of government officials and leaders will be inoculated against COVID-19 "over the coming weeks."

"I plan to get vaccinated next week as long as the White House physician says that it's appropriate to do so and do so on TV," he added. "We just want to make sure people know we have supreme confidence in the process and confidence in the safety and efficacy of the vaccine, and we wouldn't ask you to do something that we wouldn't do."

With several governors saying that they have been told to expect far fewer doses of the Pfizer/BioNTech vaccine in the coming weeks, Azar cited "a miscommunication."

"There's nothing actually to fix. There was some misunderstanding," he said. "We had put into the planning tool some base scenarios just so they could do some rough work on planning. The allocations, though, are always what Pfizer tells us or Moderna now tells us is available and ready for shipment. We've always said this week that they would have 2 million doses of Pfizer available for next week for an allocation. We'll work to clear up any misunderstanding they've got, but it's really just a miscommunication between the governors and us."

Azar said his wife, Jennifer, is "doing very well" after recently testing positive for COVID-19, and that he tested negative himself "just minutes ago."

"We're following all the CDC protocols, I've talked directly to director Redfield as well as the White House physicians of doing exactly what they say to do," he said.

There were 233,271 new cases of COVID-19 confirmed in the United States on Thursday, bringing the country's cumulative total soaring past 17 million, according to a real-time count kept by Johns Hopkins University.

It's the 45th straight day that the U.S. has reported more than 100,000 newly diagnosed infections, and the second straight day with over 200,000. Thursday's tally falls just under the country's all-time high of 247,403 new cases confirmed a day earlier, according to Johns Hopkins data.

An additional 3,270 deaths from the disease were also registered nationwide on Thursday, down from a peak of 3,656 fatalities recorded the previous day. It's only the fifth time since the pandemic began that the country has reported more than 3,000 COVID-19 deaths in a single day, according to Johns Hopkins data.

A total of 17,212,496 people in the U.S. have been diagnosed with COVID-19 since the pandemic began, and at least 310,782 of them have died, according to Johns Hopkins data. The cases include people from all 50 U.S. states, Washington, D.C., and other U.S. territories as well as repatriated citizens.

Much of the country was under lockdown by the end of March as the first wave of pandemic hit. By May 20, all U.S. states had begun lifting stay-at-home orders and other restrictions put in place to curb the spread of the novel coronavirus. The day-to-day increase in the country's cases then hovered around 20,000 for a couple of weeks before shooting back up over the summer.

The numbers lingered around 40,000 to 50,000 from mid-August through early October before surging again to record levels, crossing 100,000 for the first time on Nov. 4 and reaching 200,000 for the first time on Nov. 27.

Former U.S. President Jimmy Carter plans to get vaccinated for COVID-19, his foundation announced Thursday night.

"After consulting with his doctors, President Carter is looking forward to receiving the COVID-19 vaccine when it is available to him," The Carter Center wrote in a statement on Twitter.

Carter has not said when he will receive the vaccine or whether it will be on camera like other former presidents have indicated they will do.

All living former U.S. presidents have now announced they will get the vaccine.