A visitor wears a mask while doing pushups on a park bench with a view of the Hollywood sign from Griffith Park amid the COVID-19 pandemic Tuesday, March 9, 2021, in Los Angeles. (AP Photo/Marcio Jose Sanchez)

White flags, placed by Gov. John Bel Edwards' office and representing every Louisiana death from COVID-19, are displayed outside the state Capitol, Tuesday, March 9, 2021, are near the statue of former Gov. Huey Long in Baton Rouge, La. (AP Photo/Melinda Deslatte) Slug BC-LA--Virus Outbreak-Louisiana Gov. John Bel Edwards' office placed

FILE - In this Sept. 27, 2019, file photo, Alaska Gov. Mike Dunleavy speaks at a news conference in Anchorage, Alaska. Dunleavy on Tuesday, March 9, 2021, announced that the COVID-19 vaccine is available for all individuals who live or work in Alaska and are age 16 and older, making Alaska the first state in the nation to remove eligibility requirements. (AP Photo/Mark Thiessen)

Shagufta Bokharee, of Monroeville, and others wait the required amount of time after receiving the COVID vaccine, Tuesday, March 9, 2021, at the Monroeville Convention Center in Monroeville. Allegheny Health Network (AHN) and the Monroeville Chamber of Commerce partnered to provide the COVID-19 vaccinations to 5,100 area residents. Vaccine recipients will return to the Monroeville Convention Center on Tuesday, March 30th, to receive a second dose of the vaccine. (Pittsburgh Post-Gazette via AP)

A pedestrian wearing a mask to protect against the spread on COVID-19 passes murals painted on a boarded-up business in downtown Austin, Texas, Tuesday, March 9, 2021. Texas Gov. Greg Abbot's mask mandate for the state ends Wednesday. (AP Photo/Eric Gay)

Juan Tenorio and his daughters, Abagail, 20, and Isabel, 18, walk past a sign encouraging masking at the Austin Motel in Austin, Texas, on Tuesday March 9, 2021, the day before the statewide mask mandate was to end and Texas was to open 100 percent. ( Jay Janner/Austin American-Statesman via AP)

Diane Wendt, a curator at the Museum of American History, displays a small glass tube containing one of the original batches of polio vaccine on Monday, March 8, 2021, in Washington. The museum has acquired vials and material from the first dose of COVID-19 vaccine in the U.S. (AP Photo/Ashraf Khalil)

House Budget Committee Chairman John Yarmuth, D-Ky., center, is flanked by Ways and Means Committee Chairman Richard Neal, D-Mass., left, and Majority Whip James Clyburn, D-S.C., at a news conference ahead of the vote on the Democrat's $1.9 trillion COVID-19 relief bill, at the Capitol in Washington, Tuesday, March 9, 2021. (AP Photo/J. Scott Applewhite)

A woman wearing a face mask to protect against coronavirus, walks along an empty street in Old Town in Vilnius, Lithuania, Tuesday, March 9, 2021. The quarantine restrictions have contributed to slowing the spread of the coronavirus (COVID-19) in Lithuania, but morbidity rates are still high. (AP Photo/Mindaugas Kulbis)

Women wearing face masks to protect against coronavirus shop at the Kalvarijos market in Vilnius, Lithuania, Tuesday, March 9, 2021. The quarantine restrictions have contributed to slowing the spread of the coronavirus (COVID-19) in Lithuania, but morbidity rates are still high. (AP Photo/Mindaugas Kulbis)

A man takes a selfie as a nurse injects him with a dose of the Pfizer COVID-19 vaccine during a mass vaccination campaign for people over age 60, in Panama City, Tuesday, March 9, 2021. On Tuesday, Panama mark their first year on Pandemic (AP Photo/Arnulfo Franco)

FILE - In this Thursday, Oct. 1, 2020, file photo, Maryland Gov. Larry Hogan speaks during a news conference in Annapolis, Md. On Tuesday, March 9, 2021, Hogan announced that some restrictions on businesses will be lifted later in the week. For example, on Friday at 5 p.m., limits will be lifted on outdoor and indoor dining at restaurants and bars, but people will still need to be seated and distanced. (AP Photo/Brian Witte, File)

Neal Browning poses for a photo, Tuesday, March 9, 2021, in Bothell, Wash., north of Seattle. Earlier in the day, Browning, who was the second person to receive a shot nearly a year ago in the first-stage study of the Moderna COVID-19 vaccine, received a third shot as part of a new study of a one-year booster dose of the Moderna vaccine, which is now being widely used in worldwide vaccination efforts. Browning said that he has felt well since getting the third shot, except for some arm pain. (AP Photo/Ted S. Warren)