A top China official signals a commitment to ‘zero Covid’ as Shanghai battles an outbreak.

As Shanghai struggles to contain an Omicron outbreak, a top Chinese official vowed to adhere to a “zero Covid” policy to stamp out the virus in the shortest time possible.

During a visit to Shanghai on Saturday that analysts said indicated the central government’s high level of concern about the situation there, a Chinese vice premier, Sun Chunlan, urged improvement in the city’s coronavirus testing capacities and the expansion of makeshift hospitals and isolation centers to quarantine those infected with the virus, according to Chinese state media on Sunday.

Over the past month, Shanghai, China’s largest city, has faced one of the country’s largest coronavirus outbreaks since the pandemic began two years ago. After weeks of targeted restrictions, like neighborhood shutdowns, Shanghai officials last week pivoted to a more sweeping lockdown that closed off the metropolitan area in two stages — the eastern part of the city, followed by the western portion — for mass testing.

But mismanagement of lockdowns and other restrictions have led to growing discontent and confusion across the city. Social media posts expressing anger, desperation and frustration have flooded the Chinese internet. Residents have been unable to get help for life-threatening situations through official channels. Patients could not secure their regular medical assistance. Infected parents have been separated from their toddlers. And residents locked indoors scrambled to find essential supplies.

Many have wondered why infected residents must go to isolation centers instead of isolating at home. Ms. Sun’s instructions offered little hope that Covid policies in the city would relax anytime soon. Instead she called for officials to do a better job meeting residents’ basic needs even under lockdowns.

“It is an arduous task and huge challenge to combat the Omicron variant while maintaining the normal operation of core functions in a megacity,” she said.

With Shanghai being a critical economic and industrial hub, Ms. Sun stressed the strict implementation for factory bubbles for key industries, a “closed loop” system that is similar to the one used during the recent Olympic Games, to ensure their normal operations and the stability of supply and industrial chain.

Shanghai’s health commission on Sunday reported 8,226 confirmed new cases, of which 7,788 were asymptomatic. The city has seen a tenfold increase in daily new cases, from just 758 cases two weeks ago. Over 30,000 cases were identified in the last month.

On Sunday, the city stepped up its testing efforts by ordering all citizens to conduct their own rapid tests before the city carried out another round of mass P.C.R. testing the next day.

Echoing Ms. Sun’s pledge, a Shanghai health official said at a news conference on Sunday that the city was taking steps, through testing and other measures, to achieve “zero Covid” as soon as possible.