Medical staff in Belgrade, Serbia on February 5, 2021. Vaccination of employees in the city's social protection institutions has begun at the Belgrade Fair, who have expressed interest in receiving the Russian Sputnik V vaccine, and according to the city secretary for social protection Natasa Stanisavljevic, about 150 employees in those institutions will receive the vaccine today and tomorrow. (Photo by Zoran Zestic/Tanjug)

A brushtail possum whose ears and legs have been burnt from recent bushfires sits in a cage before being transported to a wildlife hospital, in Batemans Bay, South of Sydney, Australia, 14 January 2020. (Photo by Steven Saphore/EPA/EFE)

A man sets himself on fire during protest rallies in front of the presidential office in Kiev, Ukraine on February 26, 2020. The man, who called himself Oleksandr Burlakov, said subsequently that his motive was to draw the attention of the authorities to his plight, related to the ownership of the land parcel. (Photo by Ihor Behus/Reuters)

A PSE&G utility worker watches the Navy's Blue Angels and the Air Force's Thunderbirds conduct “a collaborative salute” to honor those battling the COVID-19 pandemic with a flyover of New York and New Jersey, Tuesday, April 28, 2020, in this view from Jersey City, N.J. (Photo by Charles Sykes/Invision/AP Photo)

A boy with his bike is seen as rainbow appears after a rainfall in Edremit district of Van province in Turkey on July 08, 2020. (Photo by Ozkan Bilgin/Anadolu Agency via Getty Images)

A man wearing a water-filled helmet in which a goldfish swims performs an act titled “Aquaman” during the Night Festival 2016 in Singapore, 20 August 2016. The ninth edition of the festival will run from 19 to 27 August and features installations and performances by a range of international and local artists. (Photo by Wallace Woon/EPA)

Sugar gliders, Candy and Popcorn, enjoy their favourite food, Nectar, at Wild Life Sydney Zoo on February 14, 2017 in Sydney, Australia. The treat made up of honey, high protein baby cereal and egg yolks is the human equivalent to chocolate to the Sugar Gliders. St. Valentine's Day or the Feast of Saint Valentine began as a celebration of the early Christian Saint Valentinus. From the 18th Century onwards it has steadily transformed into a celebration of romantic love and sentiment in many countries around the world. (Photo by James D. Morgan/Getty Images)

A woman argues as Belarus police block a street during an opposition rally in Minsk, Belarus, Saturday, March 25, 2017. Over the past two months, protests have broken out across the country of 9.5 million, sometimes attracting thousands – initially they were focused on the labor law but have grown to encompass calls for the resignation of President Alexander Lukashenko, whom critics call Europe's last dictator. (Photo by Sergei Grits/AP Photo)