People board a train at the West Railway Station on January 7, 2012 in Beijing, China. China's railways are bracing themselves as millions of migrant labourers are set to leave cities for their native villages to celebrate the Chinese New Year. (Photo by Lintao Zhang/Getty Images)

A Chinese woman wears a protective mask as she shops in a market on February 6, 2020 in Beijing, China. The number of cases of a deadly new coronavirus rose to more than 28000 in mainland China Thursday, days after the World Health Organization (WHO) declared the outbreak a global public health emergency. (Photo by Kevin Frayer/Getty Images)

Chinese epidemic control workers wear protective suits as they disinfect each other after performing nucleic acid swab test for COVID-19 on citizens at a government testing site in Xicheng District during an organized tour on June 24, 2020 in Beijing, China. While Chinese government medical officials have said they believe they have controlled the spread, authorities are trying to contain the outbreak linked to the Xinfadi wholesale food market, Beijing's biggest supplier of produce and meat. (Photo by Kevin Frayer/Getty Images)

Soldiers of China's People's Liberation Army march with their weapons during a training session for a military parade to mark the 70th anniversary of the end of World War Two, at a military base in Beijing, China, August 22, 2015. Troops from at least 10 countries including Russia and Kazakhstan will join an unprecedented military parade in Beijing next month to commemorate China's victory over Japan during World War Two, Chinese officials said. The parade on September 3 will involve about 12,000 Chinese troops and 200 aircraft, Qi Rui, deputy director of the government office organizing the parade, told reporters in Beijing on Friday. (Photo by Damir Sagolj/Reuters)

A Chinese woman poses for a photo in front of a flower display dedicated to frontline health care workers during the COVID-19 pandemic that was created with other floral decorations in advance of the country's national holidays, also known as Golden week on September 28, 2020 in Beijing, China. China will celebrate national day marking the founding of the People's Republic of China on October 1st.(Photo by Kevin Frayer/Getty Images)

Chinese workers maintain an Animatronic Dinosaurs at Gengu Dinosaurs Science and Technology company on November 13, 2019 in Zigong, Sichuan Province, China. There are hundreds of simulated dinosaur manufacturers in Zigong City. It is the largest simulated dinosaur manufacturing in China. It accounts for 95% of mainland China's production and 85% of the world's total. Its products are exported to more than 100 countries. (Photo by Lintao Zhang/Getty Images)

A demonstrator is detained by police officers during a protest in Hong Kong, China on August 31, 2019. Hong Kong police fired tear gas and water cannons and pro-democracy protesters threw petrol bombs in the latest in a series of chaotic clashes that have plunged the Chinese-ruled city into its worst political crisis in decades. (Photo by Kai Pfaffenbach/Reuters)

A woman wearing a mask walk in a street in a Yonghegong Lama temple compound seen shrouded in smog in Beijing, China, 30 November 2015. Beijing issued an orange alert for heavy smog 30 November, the highest level this year. Authorities in the Chinese capital warned of 'severe pollution' and advised the capital's 20 million inhabitants to stay indoors. (Photo by How Hwee Young/EPA)