Models painted in camouflage colours to blend in with the background pose for Chinese artist Liu Bolin's artwork “Dongji”, or Winter Solstice, on the second day after China's capital Beijing issued its second ever “red alert” for air pollution, in Beijing, China, December 20, 2015. In this artwork, Liu wants to express his concerns about China and its people, including air pollution problem, Liu told Reuters. (Photo by Kim Kyung-Hoon/Reuters)

Wang uses a mobile phone as she take a rest in her room at the accommodation where patients and their family members stay while seeking medical treatments in Beijing, China, June 23, 2016. Wang, who suffers from cervical cancer, came from Inner Mongolia to seek treatment at a specialist hospital in Beijing. (Photo by Kim Kyung-Hoon/Reuters)

This photo taken on January 30, 2020 shows officials in protective suits checking on an elderly man wearing a facemask who collapsed and died on a street near a hospital in Wuhan. AFP journalists saw the body on January 30, not long before an emergency vehicle arrived carrying police and medical staff in full-body protective suits. The World Health Organization declared a global emergency over the new coronavirus, as China reported on January 31 the death toll had climbed to 213 with nearly 10,000 infections. (Photo by Hector Retamal/AFP Photo)

A man wears a gas mask as he holds a bouquet of flowers, following the outbreak of the novel coronavirus on Valentine’s Day in Hong Kong, China on February 14, 2020. (Photo by Tyrone Siu/Reuters)

People look at a black bear at the Chengdu zoo amid the coronavirus outbreak on March 26, 2020 in Chengdu, Sichuan Province of China. (Photo by Wang Lei/China News Service via Getty Images)

Sun Rongchun, 57, exercises with an improvised cervical traction device attached to a high bar at a sports complex in Shenyang, Liaoning province, China on April 9, 2019. (Photo by Sheng Li/Reuters)

In this picture taken on January 21, 2021, people visit a nightclub in Wuhan, China's central Hubei province. (Photo by Hector Retamal/AFP Photo)

This aerial photo shows bullet trains parked at a station in preparation for the upcoming Lunar New Year travel peak in Nanjing, in eastern China's Jiangsu province on January 27, 2021, as authorities have encouraged people to stay put during the Spring Festival to curb the spread of of COVID-19 coronavirus. (Photo by AFP Photo/China Stringer Network)