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 man wearing a face mask walks his dog as he pulls a trolley after shopping in Beijing on February 13, 2020. The number of deaths and new cases from China's COVID-19 coronavirus outbreak spiked dramatically on February 13 after authorities changed the way they count infections in a move that will likely fuel speculation that the severity of the outbreak has been under-reported. (Photo by AFP Photo/China Stringer Network)

In this Sunday, February 23, 2020, photo, sumo wrestlers wearing masks arrive at Shin Osaka railway station in Osaka, western Japan. A viral outbreak that began in China has infected more than 79,000 people globally. The World Health Organization has named the illness COVID-19, referring to its origin late last year and the coronavirus that causes it. (Photo by Kyodo News via AP Photo)

Men wear masks as they sit in the metro in Prague, Czech Republic, 17 March 2020. According to media reports, the Czech government decided to impose a two-week quarantine in the country on the evening of 15 March, and ban all international travel from 16 March 2020. Currently 383 cases of the coronavirus SARS-CoV-2, which causes the Covid-19 disease, have been officially confirmed in Czech Republic. (Photo by Martin Divisek/EPA/EFE)

An member of the group “Pause the System” wears a face mask as she protests in front of the entrance to Downing Street in London, Friday, March 20, 2020. For most people, the new coronavirus causes only mild or moderate symptoms, such as fever and cough. For some, especially older adults and people with existing health problems, it can cause more severe illness, including pneumonia. (Photo by Frank Augstein/AP Photo)

An employee of cake shop prepares chocolate Easter bunnies with masks in Lykovrisi, northern Athens, on Wednesday, April 8, 2020. Cake shops and bakeries in Greece have remained open during a strict circulation ban in Greece to contain the spread of the COVID-19, but authorities have intensified a crackdown on lockdown violations ahead of Easter, which is celebrated by Orthodox Christians on April 19. Greece's Orthodox Church says it will not permit any public gatherings for Easter services. (Photo by Thanassis Stavrakis/AP Photo)

A Ballet Paraisópolis student wearing a face mask rehearses amidst the coronavirus (COVID-19) pandemic on August 13, 2020 in Sao Paulo, Brazil. The Ballet Paraisópolis is a project that teaches dance to children and young people in the Paraisópolis community in order to encourage them to seek better life opportunities. Founded in 2012 by ballerina, teacher and choreographer, Monica Tarragó, Ballet Paraisópolis has a total of 200 students and another 2,000 on the waiting list. (Photo by Alexandre Schneider/Getty Images)

A couple wearing masks as a precaution against the spread of the new coronavirus walk on the Malecon seawall at sunset in Havana, Cuba, Monday, August 31, 2020. Cuban authorities will introduce new measures starting tomorrow Tuesday aimed at containing the spread of the coronavirus in Havana among others a curfew from 7 pm until 5 am and no one without special permission will be able to enter or leave the province. The new measures will last at least 15 days. (Photo by Ramon Espinosa/AP Photo)