WASHINGTON - US President-elect Joe Biden will receive his second dose of a COVID-19 vaccine on Monday, according to his transition team.

Biden got his first dose of Pfizer-BioNTech's COVID-19 vaccine on live television on Dec. 21 in a move meant to bolster public confidence as the country seeks to break free from the pandemic's grip.

Pfizer's vaccine must be delivered in two separate rounds spaced weeks apart.

Vaccinations in the country began on Dec. 14 with healthcare workers and frontline workers. Besides Pfizer-BioNTech, the US is administering the Moderna vaccine.

As of Friday, more than 6.6 million first doses of the two vaccines had been administered, according to the nation's health agency, the Centers for Disease Control and Prevention (CDC).

Both Pfizer and Moderna's vaccines utilize what is known as messenger RNA and require two doses.