In this Monday, October 8, 2018 photo, Colombia's BMX freestyle athlete Sebastian Martinez practices at the Urban Park, at the Youth Olympic Games in Buenos Aires, Argentina. (Photo by Ian Walton/OIS/IOC via AP Photo)

Pedestrians wear masks as smoke and haze from bushfires in New South Wales blankets the CBD in Sydney, Australia, 10 December 2019. The New South Wales environment department says visibility across east and southwest Sydney was at a “hazardous” level on Tuesday morning, while air quality was poor in southwest Sydney and hazardous in northwest Sydney. (Photo by Steven Saphore/EPA/EFE)

A Malaysian Royal Guard wears a protective mask while he stands guard outside National Palace, following the outbreak of a new coronavirus in China, in Kuala Lumpur, Malaysia, February 10, 2020. (Photo by Lim Huey Teng/Reuters)

A woman prays while touching the fingers of a Buddha statue during the annual Makha Bucha Day, which celebrates Buddha's teachings, in Ang Thong, Thailand February 11, 2017. (Photo by Jorge Silva/Reuters)

Social distancing signs are pictured as models wear protective face masks before the show of designer Andres Sarda during the Mercedes Benz Fashion Week amid the coronavirus disease (COVID-19) outbreak in Madrid, Spain, September 10, 2020. (Photo by Sergio Perez/Reuters)

Masked up revellers hit the town in Sheffield, United Kingdom on October 10, 2020 before the Prime Minister introduces a three-tier lockdown system that will see hospitality venues shut in virus hotspots. (Photo by London News Pictures/The Sun)

Model Joanna Krupa poses during a protest against animals in circuses, in front of the Houses of Parliament in London, Britain, September 11, 2017. (Photo by Hannah McKay/Reuters)

Dancers perform on stage during the Crazy Horse Paris “Forever Crazy” Media Call at The MasterCard Theatres at Marina Bay Sands on October 11, 2017 in Singapore. Forever Crazy consists of a series of highly aesthetic and visual tableaus presented by a classically trained dancers clad only in textured lighting and projection. The show runs from 11 October 2017 till 22 October 2017 in Singapore. (Photo by Suhaimi Abdullah/Getty Images)