Shanghai, which reported just 16 COVID-19 cases for Wednesday, will conduct mass testing drives every weekend until the end of July in the latest display of the lengths authorities are going to in order to adhere to the nation’s zero tolerance approach to the virus.

A temporary lockdown will also be imposed on residential complexes where a COVID-19 case is detected in the week leading up to the weekend testing, Zhao Dandan, an official with the Shanghai Municipal Health Commission said at a briefing Wednesday. The lockdown will be lifted once everyone in the compound has been tested, he said.

In an effort to detect cases early and break transmission chains, the city’s residents will need to take nucleic acid tests at least once a week until the end of July, with workers at supermarkets, barbers, drugstores, shopping malls and restaurants required to undergo daily testing. Delivery workers need to take both a nucleic acid and rapid antigen tests every day. Staff at banks, gas companies and industrial entities should also do an antigen test every day.

The latest policy measure in China’s financial hub, which emerged from a bruising two-month lockdown earlier this month, shows the government’s increasing reliance on frequent mass testing to stick to its "COVID zero" stance in the face of the hyper-infectious omicron variant. Tens of thousands of lab testing booths are being set up across large cities to allow frequent swabbing to help uncover infection chains early and avert economically-crushing lockdowns.

The weekend mass-testing plan also underscores authorities’ unease with COVID-19’s intractable community spread despite repeated testing and harsh restrictions. Shanghai reported two new cases outside of government quarantine facilities on Wednesday and sent scores of close contacts to isolate to prevent further spread.

Beijing has also seen another virus cluster emerging from a bar just days after the virus’s community spread was declared to have been curbed. The bar cluster has led to more than 200 cases and triggered fresh rounds of mass testing in parts of the city.

The capital reported 18 cases for Wednesday, down from 63 on Tuesday.