In this Thursday, April 2, 2020, photo, a woman holding a child walks away from the expressway gate at the border of Wuhan city in central China's Hubei province. Millions of Chinese workers are streaming back to factories, shops and offices but many still face anti-coronavirus controls that add to their financial losses and aggravation. In Wuhan police require a health check and documents from employers for returning workers. (AP Photo/Ng Han Guan)

In this Thursday, April 2, 2020, photo, a man disembarks from a bus at an expressway gate at the border of Wuhan city in central China's Hubei province. Millions of Chinese workers are streaming back to factories, shops and offices but many still face anti-coronavirus controls that add to their financial losses and aggravation. In Wuhan police require a health check and documents from employers for returning workers. (AP Photo/Ng Han Guan)

In this Thursday, April 2, 2020, photo, a woman walks from the expressway gate at the border of Wuhan city in central China's Hubei province. Millions of Chinese workers are streaming back to factories, shops and offices but many still face anti-coronavirus controls that add to their financial losses and aggravation. In Wuhan police require a health check and documents from employers for returning workers. (AP Photo/Ng Han Guan)

In this Thursday, April 2, 2020, photo, a man crosses the expressway gate at the border into Wuhan city in central China's Hubei province. Millions of Chinese workers are streaming back to factories, shops and offices but many still face anti-coronavirus controls that add to their financial losses and aggravation. In Wuhan police require a health check and documents from employers for returning workers. (AP Photo/Ng Han Guan)

In this Thursday, April 2, 2020, photo, a man assists a woman with her belongings as they cross the expressway gate at the border of Wuhan city in central China's Hubei province. Millions of Chinese workers are streaming back to factories, shops and offices but many still face anti-coronavirus controls that add to their financial losses and aggravation. In Wuhan police require a health check and documents from employers for returning workers. (AP Photo/Ng Han Guan)

In this Thursday, April 2, 2020, photo, a man and woman carry eggs as they cross the expressway gate at the border into Wuhan city in central China's Hubei province. Millions of Chinese workers are streaming back to factories, shops and offices but many still face anti-coronavirus controls that add to their financial losses and aggravation. In Wuhan police require a health check and documents from employers for returning workers. (AP Photo/Ng Han Guan)

In this Thursday, April 2, 2020, photo, residents cross the expressway gate at the border into Wuhan city in central China's Hubei province. Millions of Chinese workers are streaming back to factories, shops and offices but many still face anti-coronavirus controls that add to their financial losses and aggravation. In Wuhan police require a health check and documents from employers for returning workers. (AP Photo/Ng Han Guan)