Students wearing masks as a precaution amid the spread of COVID-19 put away a Cuban flag so it does not get wet in the rain on their first day of school after months without face-to-face classes in Havana, Cuba, Monday, November 8, 2021. As Cuba approaches the announced date of Nov. 15 for the reopening of the entire country to the world, getting children back to school is one of its priorities. (Photo by Ramon Espinosa/AP Photo)

Icicles are seen on a handrail along the coast at Donggang business district in Dalian, Liaoning province, China on December 27, 2018. (Photo by Reuters/China Stringer Network)

A boy covers his head with fallen leaves as he enjoys a stroll with his family in a park in downtown Frankfurt, Germany, November 6, 2016. (Photo by Kai Pfaffenbach/Reuters)

A man impersonating North Korean leader Kim Jong Un gestures as he stands before North Korean cheerleaders attending the Unified Korean ice hockey game against Japan during the Pyeongchang 2018 Winter Olympic Games at the Kwandong Hockey Centre in Gangneung on February 14, 2018. (Photo by Yelim Lee/AFP Photo)

Malaysian firemen make their way to a designated area to spray disinfectant, in an effort to combat coronavirus and COVID-19, at the entrance to a school in Kuala Lumpur, Malaysia, 14 April 2020. According to media reports, Malaysia has confirmed over 4,000 cases of coronavirus and COVID-19. (Photo by Ahmad Yusni/EPA/EFE/Rex Features/Shutterstock)

Medical personnel jump in the COVID-19 unit at the CHR Centre Hospitalier Regional de la Citadelle Hospital, during the coronavirus disease (COVID-19) outbreak, in Liege, Belgium, April 22, 2020. (Photo by Yves Herman/Reuters)

A woman wears a face mask in the part of the city near neighbourhoods known for burning coal for heating in Ulaanbaatar, Mongolia January 26, 2017. Not many people in Ulaanbaatar wear masks to protect themselves against pollution. (Photo by B. Rentsendorj/Reuters)

In this Saturday, April 8, 2017 photo, a keeper walks camels to the Al Marmoom Camel Racetrack, in al-Lisaili about 40 km (25 miles) southeast of Dubai, United Arab Emirates. Camel racing is a big-money sport and fast thoroughbreds can fetch well over a million dollars. As rising temperatures across Gulf Arab countries signal the end of the winter camel racing season, Dubai is wrapping up its races with the annual Al Marmoom Heritage Festival that has drawn thousands of camels from across the oil-rich Gulf. (Photo by Kamran Jebreili/AP Photo)