Social distancing markers to help stop the spread of the COVID-19 pandemic, are seen outside a food distribution center in the Brooklyn borough of New York, the United States, on April 3, 2020. (Photo by Michael Nagle/Xinhua)

Social distancing markers to help stop the spread of the COVID-19 pandemic, are seen outside a food distribution center in the Brooklyn borough of New York, the United States, on April 3, 2020. (Photo by Michael Nagle/Xinhua)

A poster asking people to follow the social distancing measures to help stop the spread of the COVID-19 pandemic is seen outside a drugstore in the Brooklyn borough of New York, the United States, on April 3, 2020. (Photo by Michael Nagle/Xinhua)

People wearing face masks wait in line outside a grocery store in the Brooklyn borough of New York, 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 Michael Nagle/Xinhua)

People shop for face masks, gloves and hand sanitizers on Atlantic Avenue in the Brooklyn borough of New York, 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 Michael Nagle/Xinhua)

People shop for face masks, gloves and hand sanitizers on Atlantic Avenue in the Brooklyn borough of New York, 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 Michael Nagle/Xinhua)

A pedestrian wearing a face mask is seen in a street in the Brooklyn borough of New York, 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 Michael Nagle/Xinhua)