Revellers in Leeds, United Kingdom were excited to be out and about again on July 18, 2021. At a minute past midnight, England dropped most of its remaining Covid-19 social restrictions, such as those requiring indoor mask-wearing and limits on group gatherings. These changes come despite rising infections, pitting the country's vaccination programme against the virus's more contagious Delta variant. (Photo by Ioannis Alexopoulos/PA Wire Press Association via Getty Images)

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 female tourist wears a protective face mask on the street, following an outbreak of the coronavirus disease (COVID-19), in Tokyo, Japan on March 10, 2020. (Photo by Hannibal Hanschke/Reuters)

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 four-legged robot dog called SPOT patrols a park as it undergoes testing to be deployed as a safe distancing ambassador, following the coronavirus disease (COVID-19) outbreak, in Singapore on May 8, 2020. (Photo by Edgar Su/Reuters)

South Korean performers participate in a re-enactment of the battle of the Korean war during the ceremony to mark the 70th anniversary of the Korean War in Cheorwon, near the border with North Korea on June 25, 2020 in Cheorwon, South Korea. Over 66,000 South Koreans have been separated from their families during the Korean War which started on June 25, 1950, and effectively split the Korean Peninsula into two over the 3-year conflict. (Photo by Chung Sung-Jun/Getty Images)

A model waits backstage during a show of the third bi-annual Budapest Central European Fashion Week in Budapest, Hungary, 30 March 2019. (Photo by Zoltan Balogh/EPA/EFE)

An Indigenous man stands under a water fountain outside a government building in Brasilia, on April 26, 2019, during the last day of a protest camp. Approximately 4,000 indigenous people from different tribes are taking part in protests during the Indigenous National Mobilization (MNI) week, a mobilization which seeks to tackle territorial rights' negotiations with the government. (Photo by Carl De Souza/AFP Photo)