A woman smokes a cigarette next to man wearing a mask during lunch hour at the central business district in Singapore September 29, 2015. The 3-hour haze Pollutant Standards Index (PSI) reached a high of 173 at 8am on Tuesday, according to the National Environment Agency. Slash-and-burn agriculture in neighboring Indonesia has blanketed Singapore in a choking haze for weeks. (Photo by Edgar Su/Reuters)

A walruses at Hagenbeck Zoo in Hamburg, Germany on July, 7, 2015. (Photo by Werner Struss/Startraks action)

This year’s World Nomad Games, a celebration of nomadic heritage, took place in the Issyk-Kul province of Kyrgyzstan. Eleanor Moseman photographed female competitors who had travelled from all over central Asia and eastern Europe, and explored the difficulties and challenges they face as competitors. (Photo by Eleanor Moseman/The Guardian)

A demonstrator wearing a mask is seen during a protest against the government's restrictions amid the coronavirus disease (COVID-19) outbreak, in Berlin, Germany, August 1, 2020. (Photo by Christian Mang/Reuters)

School leavers celebrate their graduation in Moscow's Red Square in Moscow, Russia on June 20, 2019. (Photo by Artyom Geodakyan/TASS)

A woman wearing a face mask takes a photo on her phone in Covent Garden, London, Thursday, December 3, 2020. Britain became the first country in the world to authorize a rigorously tested COVID-19 vaccine Wednesday and could be dispensing shots within days – a historic step toward eventually ending the outbreak that has killed more than 1.4 million people around the globe. (Photo by Alberto Pezzali/AP Photo)

An actor dressed as Santa Claus and wearing a face mask to protect against coronavirus infection speaks with a boy during the New Year celebration in a shopping mall in St.Petersburg, Russia, Saturday, January 2, 2021. (Photo by Dmitri Lovetsky/AP Photo)

A man waits with his camel to take part in a camel decoration competition at the Nagaur Cattle Fair, where animals like camels, cows, horses, and bulls are brought to be sold or traded, in Nagaur, in the desert state of Rajasthan, India February 2, 2017. (Photo by Himanshu Sharma/Reuters)