Shanghai is currently carrying out a week-long campaign to screen all residents with nucleic acid and antigen testing, the municipal government announced on Monday.

The government urged the public to participate in the tests, which are aimed at identifying infections and halting the spread of the virus.

During this campaign, which kicked off on Friday, residents in lockdown zones will undergo nucleic acid tests once daily, while those in controlled zones will take antigen tests on Monday, Tuesday, and Thursday, and nucleic acid tests on Wednesday.

Residents in precautionary zones are required to take antigen tests twice during the seven days.

The municipality had on April 12 implemented an epidemic control system that categorizes communities according to three COVID-19 risk levels: lockdown, controlled and precautionary.

Shanghai reported 2,417 locally transmitted cases and 19,831 asymptomatic infections on Sunday.

The government also pointed out that, over the past three days, the situation in the districts of Pudong, Songjiang, and Qingpu had continued to improve, while that of the districts of Minhang, Xuhui, Huangpu, Baoshan, Yangpu, Hongkou, Changning and Jiading had remained mostly stable with slight fluctuations. Meanwhile, the number of cases have been rebounding in the districts of Putuo and Jing'an, and the epidemic situation in the districts of Fengxian, Jinshan, and Chongming have stabilized.