Photo taken in Arlington, Virginia, the United States, on Nov. 7, 2020, shows the live stream of U.S. Democratic nominee Joe Biden delivering a speech in Wilmington, Delaware.(Xinhua/Liu Jie)

President-elect Joe Biden, who is considered in the high-risk age category for COVID-19, got inoculated after top U.S. infectious disease expert Anthony Fauci strongly recommended that he do so.

WASHINGTON, Dec. 21 (Xinhua) -- U.S. President-elect Joe Biden on Monday received the first dose of the coronavirus vaccine during a televised event in his home state of Delaware.

The 78-year-old former vice president was administered the Pfizer BioNTech coronavirus vaccine, which requires a second dose weeks apart to reach 98 percent efficacy. Biden's vaccination followed that of his wife Jill Biden earlier on the same day.

"What I want to say is we owe these folks an awful lot," Biden, donning a black mask, said after getting the shot at ChristianaCare Hospital in Newark, Delaware. "The scientists and the people who put this together, the front line workers, the people who were the ones who actually did the clinical work, it's just amazing. I wish we had time to take you through the whole hospital to see how busy and incredible you all are. And we owe you big. We really do."

Biden, who is considered in the high-risk age category for COVID-19, got inoculated after top U.S. infectious disease expert Anthony Fauci strongly recommended that he do so. Fauci has been named Biden's chief medical adviser when the president-elect takes office in January.

It's not clear when the Bidens will receive the second doses.

"I'm looking forward to the second shot. So is Jill," Biden said.

A healthcare worker prepares the administration of the COVID-19 vaccine at Long Island Jewish Medical Center in New York, the United States, on Dec. 14, 2020. (Xinhua/Wang Ying)

Jen Psaki, spokeswoman for the Biden transition team, told reporters Friday that Vice President-elect Kamala Harris and her husband, Doug Emhoff, would receive their vaccinations next week.

Vice President Mike Pence and second lady Karen Pence, together with Surgeon General Jerome Adams, were administered the vaccine Friday at an on-camera event.

The first dose of the Pfizer BioNTech vaccine, the result of U.S.-German collaboration, began to be injected to health care workers across the United States last week after getting emergency use authorization from the U.S. Food and Drug Administration (FDA), and have been delivered to 50 states, the District of Columbia and Puerto Rico.

The FDA also gave green light to the Moderna COVID-19 vaccine on Friday.

COVID-19 cases and deaths spiked during the ongoing holiday season in the United States, with total infections nearing 18 million and cumulative deaths around 318,600 as of Monday afternoon.