In this photograph taken on February 15, 2021, doctor Sergen Saracoglu (L) and nurse Yilzdiz Ayten (C) from the Bahcesaray public hospital vaccination team, arrive at the village of Guneyyamac in eastern Turkey, as part of an expedition to vaccinate residents of 65 years old or above with Sinovac's CoronaVac Covid-19 vaccine. (Photo by Bulent Kilic/AFP Photo)

Arctic wolves in their new enclosure in the wildlife park in Hanau, Germany, 10 February 2015. The pack is one of the park's main attractions, which specializes in local and European breeds. (Photo by Boris Roessler/EPA)

Dancers from the British theater company Motionhouse perform a show with excavators entitled “Traction” on the Prado beach in Marseille, France, on May 10, 2013. (Photo by Boris Horvat/AFP Photo)

A frontline worker reacts as she receives a dose of AstraZeneca's COVISHIELD vaccine, produced by the Serum Institute of India, during the coronavirus disease (COVID-19) vaccination campaign at a medical centre in New Delhi, India, February 24, 2021. (Photo by Anushree Fadnavis/Reuters)

Medical staff administering the dose of Moderna COVID-19 Vaccine at the M A G Osmani Medical College & Hospital vaccination center in Sylhet, Bangladesh on July 26, 2021. (Photo by Md Rafayat Haque Khan/ZUMA Press Wire/Rex Features/Shutterstock)

A health worker pretends to give a shot to a girl's doll to help put her at ease before giving her a shot of the Coronavac vaccine for COVID-19, at a sports center as children age 5 – 11 start getting vaccinated in Asuncion, Paraguay, Monday, January 31, 2022. (Photo by Jorge Saenz/AP Photo)

A health worker gives a polio vaccine to a girl on a street in Lahore, Pakistan, Monday, June 27, 2022. Pakistan launched a new anti-polio drive on Monday, with the goal to vaccinate a million children across Pakistan. (Photo by K.M. Chaudary/AP Photo)

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)