
A staff member transfers a box containing nucleic acid test samples at a nucleic testing base in Hebei District of Tianjin, north China, March 19, 2022. Photo:Xinhua

A staff member works at a nucleic testing base in Hebei District of Tianjin, north China, March 19, 2022. Photo:Xinhua

Staff members heat food during work shift at the lounge of a nucleic testing base in Hebei District of Tianjin, north China, March 19, 2022. Photo:Xinhua

Staff members work at a nucleic testing base in Hebei District of Tianjin, north China, March 19, 2022. The base has a maximum daily testing capability of 15,000 tubes of 150,000 samples. Photo:Xinhua

Staff members analyze sample data at a nucleic testing base in Hebei District of Tianjin, north China, March 19, 2022. Photo:Xinhua

A staff member transfers a box containing nucleic acid test samples at a nucleic testing base in Hebei District of Tianjin, north China, March 19, 2022. Photo:Xinhua