Planes land in fog at Heathrow Airport, west London, as heavy fog covers a many parts of the south east, on April 1, 2014. (Photo by Steve Parsons/PA Wire)

A visitor stands in the exhibition “I Am A Drop In The Ocean” dedicated to the artistic and visual expressions of the protests that shook the Ukraine from November 2013 until February 2014 at the Kuenstlerhaus gallery in Vienna, Austria, Thursday, April 10, 2014. The exhibition opens its doors from April 11 until May 23, 2014. (Photo by Ronald Zak/AP Photo)

A Buddhist monk salvages a statue of a Buddhist deity from a monastery around the famous Swayambhunath stupa after it was damaged by Saturday's earthquake in Kathmandu, Nepal, Thursday, April 30, 2015. In mere seconds, Saturday's earthquake devastated a swathe of Nepal. Three of the seven World Heritage sites in the Kathmandu Valley have been severely damaged, including Durbar Square with pagodas and temples dating from the 15th to 18th centuries, according to UNESCO, the United Nations cultural agency. (Photo by Niranjan Shrestha/AP Photo)

Participants ride horses, hold spears and wear historic armoured suits of the Middle Ages as they compete during the Saint George international knight tournament in Moscow, Russia, May 3, 2015. (Photo by Maxim Zmeyev/Reuters)

Personal trainer Antonietta Orsini carries out an exercise class for her neighbours from her balcony while Italians cannot leave their homes due to the coronavirus disease (COVID-19) outbreak, in Rome, Italy, March 18, 2020. (Photo by Remo Casilli/Reuters)

Rajesh Babu, a police officer, wearing a helmet depicting coronavirus, requests a commuter to stay at home during a 21-day nationwide lockdown to limit the spreading of coronavirus disease (COVID-19), in Chennai, India, March 28, 2020. (Photo by P. Ravikumar/Reuters)

Thai Buddhist monks wear face shields to protect themselves from new coronavirus as they walk to collect alms from devotees in Bangkok, Thailand, Tuesday, March 31, 2020. (Photo by Sakchai Lalit/AP Photo)

A police officer sings as a hearse drives along a street as part of a campaign sponsored by the Colombian police and a funerary home to raise awareness during the new coronavirus pandemic in Envigado, Antioquia, Colombia, on April 1, 2020. More than 20,000 cases of COVID-19 were registered in Latin America and the Caribbean by Wednesday, according to an AFP tally using information provided by national health authorities and the World Health Organization. (Photo by Joaquin Sarmiento/AFP Photo)