A staff member takes a swab sample from a woman for nucleic acid test in Huangpu District, east China's Shanghai, May 8, 2022. Shanghai has set up fixed and mobile acid testing sites in areas such as residential communities, office spaces, business parks and in the vicinities of subway and other public transport stations in accordance with the epidemic situation.Photo:Xinhua

A staff member takes a swab sample from a woman for nucleic acid test in Huangpu District, east China's Shanghai, May 8, 2022. Shanghai has set up fixed and mobile acid testing sites in areas such as residential communities, office spaces, business parks and in the vicinities of subway and other public transport stations in accordance with the epidemic situation.Photo:Xinhua

A staff member takes a swab sample from a woman for nucleic acid test in Huangpu District, east China's Shanghai, May 8, 2022. Shanghai has set up fixed and mobile acid testing sites in areas such as residential communities, office spaces, business parks and in the vicinities of subway and other public transport stations in accordance with the epidemic situation.Photo:Xinhua

A staff member takes a swab sample from a woman for nucleic acid test in Huangpu District, east China's Shanghai, May 8, 2022. Shanghai has set up fixed and mobile acid testing sites in areas such as residential communities, office spaces, business parks and in the vicinities of subway and other public transport stations in accordance with the epidemic situation.Photo:Xinhua