President-elect Joe Biden received his first COVID-19 vaccinations on Monday in an effort to show the American people that the vaccine is safe.

“I’m ready,” Biden told Nurse Practitioner Tabe Mase before she administered the shot. 

Biden was joined by his wife, Dr. Jill Biden, who was given the innoculation earlier in the day. “She loves shots,” Biden joked of the future first lady. 

After receiving the shot, the president-elect offered praise to the Trump administration, saying it “deserves some credit getting this off the ground with Operation Warp Speed.” Still, Biden said, it is the scientists and frontline workers who deserve the most praise. 

“We owe these folks an awful lot. The scientists and people who put this together, the front line workers, the people who actually did the clinical work, it's just amazing,” Biden said. “We owe you big, we really do.”

“I'm doing this to demonstrate that people should be prepared when it's available to take the vaccine. There is nothing to be worried about, I’m looking forward to the second shot,” he added.

Biden also praised the COVID-19 vaccine developed by Moderna Inc. and the National Institutes of Health, which was distributed Monday following emergency use authorization from the Food and Drug Administration. 

Still, the president-elect encouraged Americans to continue practicing social distancing and listening to public health experts in the months to come. 

“This is just the beginning,” Biden said of the vaccine rollout. “I hope people listen to all the experts ... talking about the need to wear masks during this Christmas and New Years holidays. Wear a mask, socially distance, and if you don’t have to travel, don’t travel. It's really important, because we're still in the thick of this.”

Biden ended by thanking the frontline workers, calling them “the real heroes.”

At 78, Biden is in the high risk group for severe symptoms of the deadly virus.

Biden received the shot from Pfizer-BioNTech, which was approved for emergency use last week. According to the Biden transition team, future first lady Dr. Jill Biden received her vaccination earlier in the day.

The move comes as a second COVID-19 vaccine from Moderna is set to arrive, a light at the end of the tunnel of the deadly pandemic that has ravaged the United States. There are currently 18 million active cases in the US, and nearly 318,000 Americans have died from the deadly virus.

Beginning Friday, Dec. 18, members of Congress began receiving COVID-19 vaccinations in keeping with the protocols of the continuity of government, including House Speaker Nancy Pelosi (D-CA) and Senate Majority Leader Mitch McConnell.

“Vaccines are how we beat this virus,” McConnell wrote on Twitter.

Pelosi urged Americans to continue wearing masks and practicing social distancing as vaccines continue to be distributed.

Rep. Alexandria Ocasio-Cortez, recently re-elected by more than 70% of the vote against her Republican opponent, documented her experience receiving the vaccine on social media, answering questions and attempting to dispel myths.

“I’d never ask you to do something I wasn’t willing to do myself,” she wrote.

Vice President-elect Kamala Harris and her husband, Doug Emhoff, are expected to receive vaccinations next week.

But missing from the action has been President Donald Trump, who has spent the last week largely out of sight as he continues to stew about his election loss and floats increasingly outlandish schemes to try to remain in power. 

It’s an approach that has bewildered some top aides who see his silence as a missed opportunity for the president, who leaves office Jan. 20, to claim credit for helping oversee the speedy development of the vaccine and to burnish his legacy. 

Trump, who in the past has spread misinformation about vaccine risks, has not said when he intends to get the shot. He tweeted earlier this month that he was “not scheduled” to take it, but said he looked “forward to doing so at the appropriate time.” 

The White House has said he is still discussing timing with his doctors.

Trump was hospitalized with COVID-19 in October and given an experimental monoclonal antibody treatment that he credited for his swift recovery. A Centers for Disease Control and Prevention advisory board has said people who received that treatment should wait at least 90 days to be vaccinated to avoid any potential interference.

“When the time is right, I’m sure he will remain willing to take it,” White House spokesperson Brian Morgenstern echoed Friday. “It’s just something we’re working through.”

White House press secretary Kayleigh McEnany, however, offered a different explanation for the delay. She told reporters last week that Trump was holding off, in part, “to show Americans that our priority are the most vulnerable.”

“The President wants to send a parallel message, which is, you know, our long-term care facility residents and our frontline workers are paramount in importance, and he wants to set an example in that regard,” she said.

The CDC’s Advisory Committee on Immunization Practices has said the Pfizer-BioNTech vaccine, which was the first to receive authorization, “is safe and likely efficacious” for people who have been infected with COVID-19 and “should be offered regardless of history of prior symptomatic or asymptomatic SARS-CoV-2 infection.”

While there is no recommended minimum wait time between infection and vaccination, because reinfection is uncommon in the three months after a person is infected, the committee said people who tested positive in the preceding 90 days “may delay vaccination until near the end of this period, if desired.”

The panel also recommends that those who received Trump’s treatment put off vaccination for at least 90 days.

“Currently, there are no data on the safety and efficacy of Pfizer-BioNTech COVID-19 vaccination in persons who received monoclonal antibodies or convalescent plasma as part of COVID-19 treatment,” they wrote, recommending that vaccination “be deferred for at least 90 days, as a precautionary measure until additional information becomes available, to avoid interference of the antibody treatment with vaccine-induced immune responses.”

Surgeon General Jerome Adams cited that recommendation on CBS’s “Face the Nation” on Sunday when asked if Trump planned to receive the shot on camera.

“From a scientific point of view, I will remind people that the president has had COVID within the last 90 days. He received the monoclonal antibodies. And that is actually one scenario where we tell people maybe you should hold off on getting the vaccine, talk to your health provider to find out the right time,” Adams said.

But others, including Dr. Anthony Fauci, the nation’s top infectious diseases expert, have recommended that Trump be vaccinated without delay.

“Even though the president himself was infected, and he has, likely, antibodies that likely would be protective, we’re not sure how long that protection lasts. So, to be doubly sure, I would recommend that he get vaccinated,” he told ABC News.

The leader of the Trump administration’s vaccination program, Moncef Slaoui, told CNN’s “State of the Union” on Sunday that the vaccine is safe for those who have recovered from the virus and offers stronger and potentially longer protection than does the virus itself.

“We know that infection doesn’t induce a very strong immune response and it wanes over time. So I think, as a clear precaution, it is appropriate to be vaccinated because it’s safe,” he said. “I think people should be vaccinated, indeed.”

The Associated Press contributed to this report.