Passengers wearing face masks are seen in a subway train in Frankfurt, Germany, on Aug. 14, 2020. New infections with COVID-19 in Germany increased by 1,449 within one day to 221,413 on Friday, according to the Robert Koch Institute (RKI). (Xinhua/Lu Yang)

A pedestrian wearing a face mask walks past a Euro sculpture in Frankfurt, Germany, on Aug. 14, 2020. New infections with COVID-19 in Germany increased by 1,449 within one day to 221,413 on Friday, according to the Robert Koch Institute (RKI). (Xinhua/Lu Yang)

Passengers wearing face masks get on a train at the central railway station in Frankfurt, Germany, on Aug. 14, 2020. New infections with COVID-19 in Germany increased by 1,449 within one day to 221,413 on Friday, according to the Robert Koch Institute (RKI). (Xinhua/Lu Yang)

A sign reminding people to wear masks is seen at a subway station in Frankfurt, Germany, on Aug. 14, 2020. New infections with COVID-19 in Germany increased by 1,449 within one day to 221,413 on Friday, according to the Robert Koch Institute (RKI). (Xinhua/Lu Yang)

A passenger wearing a face mask gets on a train at the central railway station in Frankfurt, Germany, on Aug. 14, 2020. New infections with COVID-19 in Germany increased by 1,449 within one day to 221,413 on Friday, according to the Robert Koch Institute (RKI). (Xinhua/Lu Yang)

A pedestrian wearing a face mask walks past a Euro sculpture in Frankfurt, Germany, on Aug. 14, 2020. New infections with COVID-19 in Germany increased by 1,449 within one day to 221,413 on Friday, according to the Robert Koch Institute (RKI). (Xinhua/Lu Yang)