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 man wearing a hazmat suit and a mask holds a sign reading “The end is near – call grandma” at Times Square on March 14, 2020 in New York City. The World Health Organization said March 13, 2020 it was not yet possible to say when the COVID-19 pandemic, which has killed more than 5,000 people worldwide, will peak. “It's impossible for us to say when this will peak globally”, Maria Van Kerkhove, who heads the WHO's emerging diseases unit, told a virtual press conference, adding that “we hope that it is sooner rather than later”. (Photo by Johannes Eisele/AFP Photo)

A woman uses a face masks as a preventive measure against the spread of the new coronavirus, COVID-19, in Bogota, on March 19, 2020. Colombia will block all international flights from Monday for 30 days, President Ivan Duque announced on Thursday. (Photo by Raul Arboleda/AFP Photo)

An NHS worker walks past a banner supporting NHS staff outside Salford Royal Hospital on March 22, 2020 in Manchester, UK. Coronavirus (COVID-19) has spread to at least 182 countries, claiming over 13,069 lives and infecting more than 308,592 people. There have now been 5,018 diagnosed cases in the UK and 233 deaths. (Photo by Anthony Devlin/Getty Images)

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)

A South African police officer speaks to residents of the densely populated Alexandra township east of Johannesburg Friday, March 27, 2020. (Photo by Jerome Delay/AP Photo)

A police officer chases shoppers to clear the streets of the Red Light market on the first day of lockdown to stop the spread of the coronavirus disease (COVID-19) in Monrovia, Liberia on April 11, 2020. (Photo by Derick Snyder/Reuters)

A statue of a Japanese Akita dog named “Hachiko” wearing a face mask is seen near Shibuya Station Wednesday, April 8, 2020, in Tokyo. Japanese Prime Minister Shinzo Abe declared a state of emergency on Tuesday for Tokyo and six other prefectures to ramp up defenses against the spread of the new coronavirus. Hachiko has waited for his owner University of Tokyo Prof. Eizaburo Ueno at the same place by the station every afternoon, expecting him to return home for nearly 11 years even after Ueno's death at work. (Photo by Eugene Hoshiko/AP Photo)