SHANGHAI: While a two-month COVID lockdown is all but over in Shanghai, residents' relief is quickly giving way to frustration that they now face hours waiting in line for virus tests and the negative results they must show to be allowed to enter public spaces.

China's business and commercial hub lifted lockdowns for most of its 25 million residents on Wednesday. But citizens are required to have proof they've taken a COVID test within the last 72 hours in order to enter areas like malls and offices - or even to use subways and buses.

Authorities have built 15,000 testing sites and trained thousands of workers to swab throats. Still, long, snaking queues amid early summer heat of up to 31 degrees Celsius became a common sight on Wednesday and Thursday, with some people saying they queued for two hours.

One person posted a picture on social media of a sign at a booth warning of a 4.5 hour wait. The hashtag "Shanghai PCR testing" garnered 190 million views on Weibo on Thursday.

"I left the lockdown nightmare only to enter the 72-hour PCR testing nightmare," said one Shanghai resident, declining to provide her name.

"It is troublesome, but we have no choice," said another, named Xu Xiaojun. "This is for everyone's good."

Other Chinese cities including Beijing and Shenzhen have imposed similar requirements under a national zero-COVID policy that aims to cut off every infection chain.

Despite the deep discontent sparked by Shanghai's stringent curbs - some 2.5 million in the city are still under lockdown - China has vowed to stick with its approach. It says the zero-COVID policy is needed to save lives and prevent its healthcare system from being swamped, even as much of the world tries to return to normal despite ongoing infections.

That increasingly means COVID testing is becoming a feature of daily life: China's goal is to have testing sites within a 15 minute walk for everyone in large cities. 

Still, many Shanghai residents remain on edge about the possibility of going back under lockdown.

On Thursday, videos shared on social media showed people fleeing the luxury International Finance Centre (IFC) mall in the city's Lujiazui financial district after it stopped people from entering or exiting - a common practice at venues when a positive COVID test result is found.

The IFC mall, run by Sun Hung Kai Properties 0016.HK, later issued a notice saying that it had reopened at 12.30 p.m. local time after carrying out a full disinfection without confirming whether there had been a positive COVID test at the site. The mall did not respond to calls seeking further comment.

The ruling Chinese Communist Party's People's Daily newspaper on Thursday also published a commentary in which it said that the zero-COVID policy was most appropriate for China's situation. It also carried a front-page article describing how Shanghai was returning to normal.

"Great, phased results have been achieved in the defence of Shanghai."