Residents wait in line for the coronavirus test in a district in Guangzhou in southern China's Guangdong province on Sunday, May 30, 2021. The southern Chinese city of Guangzhou shut down a neighborhood and ordered residents to stay home Saturday to be tested for the coronavirus following an upsurge in infections that has rattled authorities. (AP Photo)

Body of a COVID-19 victim is prepared for burial at a Christian cemetery in New Delhi, India, Saturday, May 29, 2021. India's death toll is the third-highest reported in the world after the U.S. and Brazil. (AP Photo/Ishant Chauhan)

A doctor inoculates a woman with a dose of the Sputnik V COVID-19 vaccine during a vaccination campaign for seniors, at the Alba Caracas's hotel in Caracas, Venezuela, Saturday, May 29, 2021. (AP Photo/Matias Delacroix)

A child wearing a face mask to help curb the spread of the coronavirus reacts with a flower-shaped balloon after receiving from a masked clown during a children event in Beijing, Sunday, May 30, 2021. (AP Photo/Andy Wong)

A health worker takes a swab sample of a woman to test for COVID-19 in Kusehta village north of Prayagraj, India, Saturday, May 29, 2021. (AP Photo/Rajesh Kumar Singh)

A volunteer places American flags on Boston Common ahead of Memorial Day, Wednesday. May 26, 2021, in Boston. After more than a year of isolation, American veterans are embracing plans for a more traditional Memorial Day. They say wreath-laying ceremonies, barbecues at local vets halls and other familiar events are a welcome chance to reconnect with fellow service members and renew solemn traditions honoring the nation’s war dead. (AP Photo/Josh Reynolds)

Monks get tested for the coronavirus in a district in Guangzhou in southern China's Guangdong province on Sunday, May 30, 2021. The southern Chinese city of Guangzhou shut down a neighborhood and ordered residents to stay home Saturday to be tested for the coronavirus following an upsurge in infections that has rattled authorities. (AP Photo)

Residents get tested for the coronavirus in a district in Guangzhou in southern China's Guangdong province on Sunday, May 30, 2021. The southern Chinese city of Guangzhou shut down a neighborhood and ordered residents to stay home Saturday to be tested for the coronavirus following an upsurge in infections that has rattled authorities. (AP Photo)

A man wearing a protective face mask to help curb the spread of the coronavirus walks in a street in Kabul, Afghanistan, Sunday, May 30, 2021. (AP Photo/Rahmat Gul)

People crowd the Santa Monica Pier in Santa Monica, Calif., Saturday, May 29, 2021. Californians are celebrating the Memorial Day weekend, more upbeat than they have been for any other holiday since the pandemic began thanks to dramatically lower virus cases and increasing vaccinations. (AP Photo/Damian Dovarganes)

A health worker administers Covishield, Serum Institute of India's version of the AstraZeneca vaccine to a man during a special vaccination drive held in the premises of a government school in Hyderabad, India, Sunday, May 30, 2021. (AP Photo/Mahesh Kumar A.)

Craig DeOld, a retired Army Captain, and commander of the Boston Police VFW, replaces flags at veteran's graves Thursday, May 27, 2021, in the Fairview Cemetery in Boston. After more than a year of isolation, American veterans are embracing plans for a more traditional Memorial Day. “We’re breathing a sigh of relief that we’ve overcome another struggle, but we’re also now able to return to what this holiday is all about — remembering our fallen comrades.” (AP Photo/Josh Reynolds)