A worker produces protective suits at a workshop of a garment company in shenyang, northeast China's Liaoning Province, April 7, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

A worker produces protective suits at a workshop of a garment company in shenyang, northeast China's Liaoning Province, April 7, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

A worker produces protective suits at a workshop of a garment company in shenyang, northeast China's Liaoning Province, April 7, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

A worker produces high-flow heated respiratory humidifiers at a workshop of a medical company in shenyang, northeast China's Liaoning Province, April 13, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

Workers display a protective suit at a workshop of a garment company in shenyang, northeast China's Liaoning Province, April 7, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

A worker produces high-flow heated respiratory humidifiers at a workshop of a medical company in shenyang, northeast China's Liaoning Province, April 13, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

A worker packages high-flow heated respiratory humidifiers at a workshop of a medical company in shenyang, northeast China's Liaoning Province, April 13, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

A staff member checks stockpile of high-flow heated respiratory humidifiers at a warehouse of a medical company in shenyang, northeast China's Liaoning Province, April 13, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

A worker produces high-flow heated respiratory humidifiers at a workshop of a medical company in shenyang, northeast China's Liaoning Province, April 13, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

Workers produce high-flow heated respiratory humidifiers at a workshop of a medical company in shenyang, northeast China's Liaoning Province, April 13, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

Workers test high-flow heated respiratory humidifiers at a workshop of a medical company in shenyang, northeast China's Liaoning Province, April 13, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)

Workers produce protective suits at a workshop of a garment company in shenyang, northeast China's Liaoning Province, April 7, 2020. Companies in Shenyang have been actively manufacturing medical products including protective suits and high-flow heated respiratory humidifiers that will be exported overseas. (Xinhua/Yang Qing)