Medical worker Song Liqiang (L) sends an 81-year-old COVID-19 patient in severe condition to the CT room at the makeshift Huoshenshan (Fire God Mountain) Hospital in Wuhan, capital of central China's Hubei Province, March 20, 2020. To ensure sufficient oxygen to the COVID-19 patient, another medical worker Hu Shijie pushes an oxygen cylinder, accompanying them. Photo:Xinhua

Medical worker Song Liqiang (L) sends an 81-year-old COVID-19 patient in severe condition to the CT room at the makeshift Huoshenshan (Fire God Mountain) Hospital in Wuhan, capital of central China's Hubei Province, March 20, 2020. To ensure sufficient oxygen to the COVID-19 patient, another medical worker Hu Shijie pushes an oxygen cylinder, accompanying them. Photo:Xinhua

Medical worker Song Liqiang (L) sends an 81-year-old COVID-19 patient in severe condition to the CT room at the makeshift Huoshenshan (Fire God Mountain) Hospital in Wuhan, capital of central China's Hubei Province, March 20, 2020. To ensure sufficient oxygen to the COVID-19 patient, another medical worker Hu Shijie pushes an oxygen cylinder, accompanying them. Photo:Xinhua