Chinese authorities have tried to implement a “zero-Covid” policy, which has largely been successful in containing outbreaks and led to a low official death toll of 4,638 since the pandemic began.

But the measures, fine-tuned since the early days of the virus in Wuhan, mean near-immediate disruption to the normal pace of life, forcing people to stay at home.

Shanghai is now split into halves for staggered mass testing as authorities scramble to contain omicron. Many shops were shuttered on Tuesday, with pedestrians sparse even in the half of the city that remained open.

Restaurants offered only a takeaway service, and a long queue formed outside a McDonalds. Authorities are working to ensure food supplies after panic buying on Sunday and reports of shortages of meat and vegetables.

“We really don’t understand Shanghai’s management and control measures. There has indeed been some inconsistency,” said a 59-year-old man, who gave only his surname Cao, as he queued for groceries. “After so much time, it is not controlling the virus and the numbers are still going up.”

Local authorities are allowing some factories to implement a “closed-loop” model, isolating staff so plants can continue to churn out goods. Companies have to maintain testing protocols and ensure factory workers do not leave sites.