Members of the National Guard help motorists check in at a federally-run COVID-19 vaccination site set up on the campus of California State University of Los Angeles in Los Angeles, Tuesday, Feb. 16, 2021. (AP Photo/Jae C. Hong)

A man gets the coronavirus vaccine at an outdoor vaccination site at Lakewood Ranch Wednesday, Feb. 17, 2021, in Bradenton, Fla. (AP Photo/Chris O'Meara)

People are administered COVID-19 vaccines Thursday, Feb. 11, 2021, at a vaccination center, at Gillette Stadium, in Foxborough, Mass. (AP Photo/Steven Senne)

Emergency medical technician Alyssa Mucci, center, speaks with RN Mary McGovern, right, as they prepare to give COVID-19 vaccinations, Thursday, Feb. 11, 2021, at a vaccination center at Gillette Stadium in Foxborough, Mass. (AP Photo/Steven Senne)

President Joe Biden walks on the South Lawn of the White House after stepping off Marine One, Wednesday, Feb. 17, 2021, in Washington. Biden was returning to Washington after participating in a town hall event in Wisconsin. (AP Photo/Patrick Semansky)

Motorists wait to get their COVID-19 vaccine at a federally-run vaccination site set up on the campus of California State University of Los Angeles in Los Angeles, Tuesday, Feb. 16, 2021. (AP Photo/Jae C. Hong)