Artists perform during a show at the Great Moscow circus in Moscow, Russia, on Aug. 7, 2020. The circus opened the new season with a charity performance for medical workers and their families after a tight lockdown brought by the COVID-19 pandemic. (Photo by Alexander Zemlianichenko Jr/Xinhua)

Animal trainers perform with a tiger during a show at the Great Moscow circus in Moscow, Russia, on Aug. 7, 2020. The circus opened the new season with a charity performance for medical workers and their families after a tight lockdown brought by the COVID-19 pandemic. (Photo by Alexander Zemlianichenko Jr/Xinhua)

A medic wearing a face mask checks the body temperature of a boy before he enters the Great Moscow circus in Moscow, Russia, on Aug. 7, 2020. The circus opened the new season with a charity performance for medical workers and their families after a tight lockdown brought by the COVID-19 pandemic. (Photo by Alexander Zemlianichenko Jr/Xinhua)