Shanghai residents who tested positive during the previous screening will take PCR tests, while all others will take antigen tests and should they test positive, will also be required to take a PCR.

On March 28, the 24.9-million city went under lockdown to facilitate mass screening.

The authorities used a new scheme where areas east and south of River Huangpu closed from March 28-April 1, while those east and south of Huangpu from April 1-5. Due to the high incidence of Covid-19 infections, the authorities have extended the lockdown, without specifying the end date.

Over the past day, Shanghai detected 311 new Covid-19 cases, in addition to 16,766 asymptomatic cases which are part of a separate tally in China.

China pursues stringent zero-Covid policy, which is now tested by the wave of the Omicron strain.

Shanghai has faced a surge in Covid-19 infections in recent weeks, and the authorities redirected some international passenger flights to other Chinese cities from March 21 to May 1 to relieve the Covid-19 prevention and control sector.

(With UNI/Sputnik inputs)