A hippopotamus is sprayed with water on a hot summer day at Anna National Zoological Park in Chennai, India on April 26, 2017. (Photo by Arun Sankar/AFP Photo)

Swedish climate change activist Greta Thunberg, Isabelle Axelsson and German Luisa Neubauer take part in a climate strike protest during the 50th World Economic Forum (WEF) annual meeting in Davos, Switzerland on January 24, 2020. (Photo by Denis Balibouse/Reuters)

Wu Lingling, a nurse from Central Hospital of Shanghai Fengxian District says goodbye to her husband Zhao Kun before leaving for Wuhan at Shanghai South Railway Station in east China's Shanghai, January 27, 2020. A team comprised of 50 medical workers from 40 hospitals in Shanghai left for Wuhan City on Monday to aid the novel coronavirus control efforts there. (Photo by Ding Ting/Xinhua News AgencyAlamy Live News)

Miguel Toribio, 11, puts a pistol belonging to his father into his belt, before demonstrating newly learnt skills from military-style weapons training, to a Reuters journalist in Ayahualtempa, Mexico, February 3, 2020. (Photo by Alexandre Meneghini/Reuters)

A dog plays with a giant soap bubble in downtown Kiev, Ukraine, 06 March 2020. (Photo by Sergey Dolzhenko/EPA/EFE)

The Greyfriars Bobby statue is pictured wearing a mask as the spread of the coronavirus disease (COVID-19) continues, in Edinburgh, Scotland, Britain, March 23, 2020. (Photo by Russell Cheyne/Reuters)

A changing of the honor guard ceremony by the Tomb of the Unknown Soldier in Alexander Garden by the Kremlin Wall in Moscow, Russia on May 29, 2020. (Photo by Vladimir Gerdo/TASS)

People huddle to get on a bus after the government has eased restrictions on public transport amid concerns over the coronavirus disease (COVID-19) outbreak in Dhaka, Bangladesh, June 4, 2020. (Photo by Mohammad Ponir Hossain/Reuters)