When COVID-19 case numbers started ticking up in the southern Chinese city of Shenzhen last week, Robin Chen got in his car and fled to nearby Huizhou.

It wasn't because he feared the virus - many of his friends overseas had caught it and recovered - but he didn't want to lose his freedom again as speculation swirled that Shenzhen was headed for its second lockdown in six months.

"I do hope and think there is no reason for our government to continue this policy because it is simply unsustainable," he said after playing golf and surfing in coastal Huizhou.

Shenzhen, which borders Hong Kong, was locked down last weekend and Chen returned only after the curbs were partially lifted.

Many people in China say they are weary and frustrated that China is sticking with draconian methods to stop the spread of COVID-19, pointing to how the coronavirus appears to have mutated into a less deadly form, with the vast majority of cases in China classified as having mild or no symptoms.

China follows a zero-Covid policy, with lockdowns, frequent testing and quarantines in areas where infections break out.

The policy has kept cases extremely low but have begun this year to exact a heavy economic and psychological toll, especially as outbreaks of the highly-infectious Omicron variant continue to erupt.

The measures have given rise to desperate scenes: people fleeing in panic from an IKEA outlet in Shanghai and from the Shenzhen headquarters of tech giant Tencent after they were told the venues were being locked down because they were linked to COVID cases. Reuters has not independently verified the footage, which was shared widely online.

Heavy-handed and formulaic implementation have also drawn scorn: authorities in the city of Chengdu were criticised after videos on social media showed residents ordered to not leave their high-rise apartments to comply with the lockdown there even after a major earthquake shook their homes.

Many residents in cities such as Shenzhen, Shanghai and Chengdu, among China's largest metropolises, described the pervasive anxiety over what might happen if even a single case is found in their vicinity.

"We've worn masks and done PCR tests since the virus first appeared, and we've got vaccinated and boosted, but almost three years later we're locked down again and again," said Yan Yuegao, a supply chain manager in Shenzhen.

"For business, one of the very important things is certainty - imagine you have to travel, but you never know when and where you're going to be stopped, how can you make plans?"

'TOO SENSITIVE'

While most of the world has opted to live with the virus, China argues that its zero-Covid policy is needed to prevent its health system from being overwhelmed as well as an unacceptable loss of life. Only 61% of Chinese over 80 have completed their primary vaccination, authorities said in July.

According to the World Health Organisation, there were about 255,000 infections among China's 1.3 billion people over the past seven days, against 3.6 million infections globally.

Chinese President Xi Jinping, expected to secure a precedent-breaking third term as leader at next month's Communist Party congress, has repeatedly described the policy as "correct and effective". Chinese authorities continue to describe the COVID-19 situation as "severe and complex" and warn that they will not tolerate criticism of the policy.

This week, the chief economist of state-owned Huatai Securities, one of China's largest brokerages, published a note saying the COVID death rate might be lower than the flu. That led social media users to speculate whether voicing such a view signals that zero-COVID may ease.

By late on Thursday, many of the blogs that had reposted the post had deleted it. Huatai did not immediately respond to a request for comment, and there was no sign from officials that the policy is going to change any time soon.

"This topic is just too sensitive," said one Weibo user.