Photo taken on March 20, 2020 shows a Mexican restaurant closed due to COVID-19 epidemic in New Orleans, Louisiana, the United States. The number of COVID-19 cases in the United States topped 20,000 as of 1:30 p.m. local time on Saturday (1730 GMT), according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. (Photo by Lan Wei/Xinhua)
Photo taken on March 20, 2020 shows a library closed due to COVID-19 epidemic in New Orleans, Louisiana, the United States. The number of COVID-19 cases in the United States topped 20,000 as of 1:30 p.m. local time on Saturday (1730 GMT), according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. (Photo by Lan Wei/Xinhua)
Photo taken on March 20, 2020 shows a sign saying "Open for take out" at a restaurant in New Orleans, Louisiana, the United States. The number of COVID-19 cases in the United States topped 20,000 as of 1:30 p.m. local time on Saturday (1730 GMT), according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. (Photo by Lan Wei/Xinhua)
People wait inside cars to be tested at a drive-through COVID-19 testing site in Dallas, Texas, the United States, March 21, 2020. The number of COVID-19 cases in the United States topped 20,000 as of 1:30 p.m. Eastern Standard Time on Saturday (1730 GMT), according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. (Photo by Dan Tian/Xinhua)
Medical workers work at a drive-through COVID-19 testing site in Dallas, Texas, the United States, March 21, 2020. The number of COVID-19 cases in the United States topped 20,000 as of 1:30 p.m. Eastern Standard Time on Saturday (1730 GMT), according to the Center for Systems Science and Engineering (CSSE) at Johns Hopkins University. (Photo by Dan Tian/Xinhua)