A medical worker takes a swab sample from a resident for nucleic acid test at a community in east China's Shanghai, March 13, 2022.Photo:Xinhua

Residents queue to receive nucleic acid tests at a community in east China's Shanghai, March 13, 2022.Photo:Xinhua

A medical worker takes a swab sample from a child for nucleic acid test at a community in east China's Shanghai, March 13, 2022.Photo:Xinhua

Residents register before receiving nucleic acid tests at a community in east China's Shanghai, March 13, 2022.Photo:Xinhua