People take nucleic acid testing in Harbin

A medical worker takes a swab sample from a child at a nucleic acid testing site in Xiangfang District of Harbin, northeast China's Heilongjiang Province, March 26, 2022. (Xinhua/Wang Jianwei)

A medical worker takes a swab sample from a citizen at a nucleic acid testing site in Daoli District of Harbin, northeast China's Heilongjiang Province, March 26, 2022. (Xinhua/Zhang Tao)

Medical workers take swab samples from citizens at a nucleic acid testing site in Xiangfang District of Harbin, northeast China's Heilongjiang Province, March 26, 2022. (Xinhua/Wang Jianwei)

A medical worker takes a swab sample from a citizen at a nucleic acid testing site in Daoli District of Harbin, northeast China's Heilongjiang Province, March 26, 2022. (Xinhua/Zhang Tao)

A medical worker takes a swab sample from a citizen at a nucleic acid testing site in Xiangfang District of Harbin, northeast China's Heilongjiang Province, March 26, 2022. (Xinhua/Wang Jianwei)