Beesan al-Jubeh, (L), Palestinian under-10 national karate champion, trains with her father Sami (R) and other family members, all wearing face masks and gloves due to the COVID-19 coronavirus pandemic, outside their house in the city of Hebron in the Occupied West Bank on April 9, 2020. (Photo by Hazem Bader/AFP Photo)

Steven Busulwa, an animal keeper, runs away from a charging rhino at the Uganda Wildlife Conservation Education Center (UWEC) amid the lockdown as part of the measures taken to prevent the spread of the coronavirus disease (COVID-19), within Wakiso district, in Entebbe, Uganda on April 20, 2020. (Photo by Abubaker Lubowa/Reuters)

Buddhist believers wearing faces masks to help protect against the spread of the new coronavirus wait to attend a service to pray for overcoming the COVID-19 outbreak and to celebrate Buddha's birthday at the Chogyesa temple in Seoul, South Korea, Thursday, April 30, 2020. (Photo by Ahn Young-joon/AP Photo)

A round circle of smoke coming from the mouth of the Etna volcano is seen in the sky during an eruption on the southern Italian island of Sicily April 11, 2013. Mount Etna is Europe's tallest and most active volcano. (Photo by Antonio Parrinello/Reuters)

A visitor looks at a sculpture entitled “Couple Under an Umbrella, 2013” by artist Ron Mueck during the press day for his exhibition at the Fondation Cartier pour l'art contemporain in Paris April 15, 2013. (Photo by Charles Platiau/Reuters)

Migrants ride on top of a northern bound train toward the US-Mexico border in Juchitan, southern Mexico, Monday, April 29, 2013. Migrants crossing Mexico to get to the U.S. have increasingly become targets of criminal gangs who kidnap them to obtain ransom money. (Photo by Eduardo Verdugo/AP Photo)

Corporal of Horse Andy Radford prepares to mount his horse in the parade square at Hyde Park Barracks on April 15, 2011 in London, England. Members of the Household Cavalry gave a behind the scenes tour of many of the duties performed as part of their daily routine, including special preparation ahead of the forthcoming Royal Wedding. The Household Cavalry will perform several ceremonial duties during the summer, including the Royal Wedding on April 29, and the Queen's Birthday Parade (Trooping the Colour) in June. (Photo by Dan Kitwood/Getty Images)

Alex Plunkett, left, and Sean Hart, both of Arlington, Va., join hundreds participating in the annual International Pillow Fight Day on April 5. Massive pillow fights broke out on the Mall in Washington and in cities around the world. (Photo by Marvin Joseph/The Washington Post)