The Greyfriars Bobby statue is pictured wearing a mask as the spread of the coronavirus disease (COVID-19) continues, in Edinburgh, Scotland, Britain, March 23, 2020. (Photo by Russell Cheyne/Reuters)

Agriculture Secretary Sonny Perdue adjusts his mask before an event in the Roosevelt Room of the White House, Tuesday, May 19, 2020, in Washington. (Photo by Evan Vucci/AP Photo)

A health worker dresses in a protective suit before starting to perform the coronavirus testing in an effort to stop the spread of the coronavirus disease (COVID-19) in the Kibera slum of Nairobi, Kenya, May 26, 2020. (Photo by Baz Ratner/Reuters)

A red deer stag takes a mud bath in Wollaton Park near Nottingham, England on May 23, 2020. Gareth Williams, who took the photograph, said it was a “once in a lifetime shot”. (Photo by Gareth Williams/Kennedy News)

A changing of the honor guard ceremony by the Tomb of the Unknown Soldier in Alexander Garden by the Kremlin Wall in Moscow, Russia on May 29, 2020. (Photo by Vladimir Gerdo/TASS)

Pigeons cool down at a public fountain on a hot summer day at University Plaza in downtown Bucharest, Romania, 10 June 2020. Temperatures in Bucharest reached 30 degrees Celsius. (Photo by Robert Ghement/EPA/EFE)

A woman takes a selfie picture at the Poklonnaya Hill in western Moscow near the main building of the Moscow State University on June 17, 2020, as the air temperature approaches 30 degrees Celsius. (Photo by Alexander Nemenov/AFP Photo)

People practice yoga on a cliff at an attitude of over 2,000 meters at Laojunshan mountain to welcome upcoming International Yoga Day on June 20, 2020 in Luoyang, Henan Province of China. (Photo by VCG/VCG via Getty Images)