People wait in line to get tested for COVID-19 at a testing site in Washington, D.C., the United States, Dec. 9, 2020. (Photo by Ting Shen/Xinhua)
A healthcare worker helps people check in for COVID-19 test at a testing site in Washington, D.C., the United States, Dec. 9, 2020. (Photo by Ting Shen/Xinhua)
A healthcare worker helps people check in for COVID-19 test at a testing site in Washington, D.C., the United States, Dec. 9, 2020. (Photo by Ting Shen/Xinhua)
A healthcare worker helps people check in for COVID-19 test at a testing site in Washington, D.C., the United States, Dec. 9, 2020. (Photo by Ting Shen/Xinhua)
