Both customers and store staff wear masks inside a Chinese supermarket in Plano, a suburban city of Dallas, Texas, the United States, on April 3, 2020. U.S. President Donald Trump said on Friday the Centers for Disease Control and Prevention (CDC) now recommends that Americans wear cloth face coverings to protect against COVID-19. "The CDC is advising the use of non-medical cloth face covering as a voluntary health measure," Trump told a White House briefing. "It is voluntary. They suggested for a period of time." (Photo by Dan Tian/Xinhua)

A store staff wearing a mask puts more goods on a shelf in a Chinese supermarket in Plano, a suburban city of Dallas, Texas, the United States, on April 3, 2020. U.S. President Donald Trump said on Friday the Centers for Disease Control and Prevention (CDC) now recommends that Americans wear cloth face coverings to protect against COVID-19. "The CDC is advising the use of non-medical cloth face covering as a voluntary health measure," Trump told a White House briefing. "It is voluntary. They suggested for a period of time." (Photo by Dan Tian/Xinhua)

A lady wearing a mask shops in a supermarket in Plano, a suburban city of Dallas, Texas, the United States, on April 3, 2020. U.S. President Donald Trump said on Friday the Centers for Disease Control and Prevention (CDC) now recommends that Americans wear cloth face coverings to protect against COVID-19. "The CDC is advising the use of non-medical cloth face covering as a voluntary health measure," Trump told a White House briefing. "It is voluntary. They suggested for a period of time." (Photo by Dan Tian/Xinhua)

Both customer and store cashier wear masks inside a Chinese supermarket in Plano, a suburban city of Dallas, Texas, the United States, on April 3, 2020. U.S. President Donald Trump said on Friday the Centers for Disease Control and Prevention (CDC) now recommends that Americans wear cloth face coverings to protect against COVID-19. "The CDC is advising the use of non-medical cloth face covering as a voluntary health measure," Trump told a White House briefing. "It is voluntary. They suggested for a period of time." (Photo by Dan Tian/Xinhua)