British Prime Minister Boris Johnson visits the Pavegen stand, a company that converts footsteps into energy, at the Innovation Zone during the UK-Africa Investment Summit in London, Britain on January 20, 2020. (Photo by Leon Neal/Pool via Reuters)

A tourist carries her luggage in a flooded St. Mark's Square, in Venice, Wednesday, November 13, 2019. The high-water mark hit 187 centimeters (74 inches) late Tuesday, Nov. 12, 2019, meaning more than 85% of the city was flooded. The highest level ever recorded was 194 centimeters (76 inches) during infamous flooding in 1966. (Photo by Luca Bruno/AP Photo)

A tourist pauses for photos with her mask on at Sensoji Temple Thursday, January 30, 2020, in Tokyo. The country began evacuating Japanese citizens on Wednesday from the Chinese city Wuhan hardest-hit by the virus. (Photo by Jae C. Hong/AP Photo)

An air plane takes off from the airport as air traffic is effected by the spread of the coronavirus disease (COVID-19) in Frankfurt, Germany, March 16, 2020. (Photo by Kai Pfaffenbach/Reuters)

In this Wednesday, April 15, 2020 file photo, a motorcycle delivery man rides past a billboard urging people to stay home over the coronavirus pandemic in Dubai, United Arab Emirates. Wealthier Western countries are considering how to ease lockdown restrictions and start taking gradual steps toward reviving business and daily life. But many developing countries, particularly in the Middle East and Africa, can hardly afford the luxury of any misstep. (Photo by Jon Gambrell/AP Photo/File)

Fox cubs venture out from their den under a popular boardwalk alongside Lake Ontario during the global outbreak of the coronavirus disease (COVID-19), in Toronto, Ontario, Canada on April 22, 2020. (Photo by Carlos Osorio/Reuters)

In this Tuesday, April 16, 2019, file photo, a visitor posing for a photo walks though azalea blossoms at Nezu Shrine during a day of mild spring weather in Tokyo. Nezu Shrine is one of the oldest shrines in Tokyo. (Photo by Eugene Hoshiko/AP Photo/File)

Tea garden workers carry sacks of tea leaves at Fatikchera tea garden estate on the outskirts of Agartala, India, May 10, 2016. (Photo by Jayanta Dey/Reuters)