
People receive COVID-19 tests inside the Wiener Stadthalle in Vienna, Austria, Dec. 4, 2020. Vienna's COVID-19 mass tests will last from Dec. 4 to Dec. 13.Photo:Xinhua

People receive COVID-19 tests inside the Wiener Stadthalle in Vienna, Austria, Dec. 4, 2020. Vienna's COVID-19 mass tests will last from Dec. 4 to Dec. 13.Photo:Xinhua

People receive COVID-19 tests inside the Wiener Stadthalle in Vienna, Austria, Dec. 4, 2020. Vienna's COVID-19 mass tests will last from Dec. 4 to Dec. 13.Photo:Xinhua

People receive COVID-19 tests inside the Wiener Stadthalle in Vienna, Austria, Dec. 4, 2020. Vienna's COVID-19 mass tests will last from Dec. 4 to Dec. 13.Photo:Xinhua

People queue to receive COVID-19 tests outside the Wiener Stadthalle in Vienna, Austria, Dec. 4, 2020. Vienna's COVID-19 mass tests will last from Dec. 4 to Dec. 13.Photo:Xinhua

People queue to receive COVID-19 tests outside the Wiener Stadthalle in Vienna, Austria, Dec. 4, 2020. Vienna's COVID-19 mass tests will last from Dec. 4 to Dec. 13.Photo:Xinhua