A hot air balloon depicting a dog that participates in the International Hot Air Balloon Festival, flies over Leon, Guanajuato state, Mexico, on November 14, 2020, amid the COVID-19 coronavirus pandemic. The festival, in which 100 air balloons participate, was held without spectators to avoid crowds and prevent contagion. (Photo by Ulises Ruiz/AFP Photo)

A cat sits on the empty Great Wall on February 23, 2021 in Beijing, China. Affected by the new coronavirus (COVID-19), the number of visitors to Mutianyu Great Wall in 2020 dropped by about 60%. (Photo by Lintao Zhang/Getty Images)

A Guarani boy pets a puppy in the Mata Verde Bonita village, in Marica, Rio de Janeiro state, Brazil, Thursday, February 25, 2020, where healthcare workers are making the rounds with coolers containing doses of China's Sinovac COVID-19 vaccine as part of a mass immunization program aimed at inoculating all of Rio's 16 million residents by the end of the year. (Photo by Bruna Prado/AP Photo)

Riders compete during a kok boru, also called ulak tartysh, a traditional game in which players on horseback manoeuvre with a goat's carcass and score by putting it into the opponents' goal outside Sokuluk village, 20 km (12,5 miles) west of Bishkek, Kyrgyzstan, Tuesday, March 30, 2021. (Photo by Vladimir Voronin/AP Photo)

In this September 17, 2010 file photo a little brown bat is photographed in La Crosse Wis. Researchers for the first time found that little brown bats appear to be showing resistance to white-nose syndrome, which has killed millions of bats across North America. (Photo by Peter Thomson/La Crosse Tribune via AP Photo)

Long shadows are cast by players as Mitch Wallis of the Bulldogs passes the ball during the 2016 AFL Round 08 match between the Melbourne Demons and the Western Bulldogs at the Melbourne Cricket Ground, Melbourne on May 15, 2016. (Photo by Scott Barbour/AFL Media/Getty Images)

Revellers attend the 25th edition of the Sziget Festival on August 9, 2017 in Budapest, Hungary. The Sziget Festival, one of the largest music and cultural festivals in Europe, celebrates its 25th anniversary in 2017, taking place from August 9-16 on the Hajogyari Sziget in Budapest. (Photo by Laszlo Mudra/Rockstar Photographers)

This image made available by the Johns Hopkins University Applied Physics Laboratory on Wednesday, May 31, 2017 depicts NASA's Solar Probe Plus spacecraft approaching the sun. On Wednesday, NASA announced it will launch the probe in summer 2018 to explore the solar atmosphere. It will be subjected to brutal heat and radiation like no other man-made structure before. (Photo by Johns Hopkins University Applied Physics Laboratory via AP Photo)