SHANGHAI – China’s top health officials said a sweeping overhaul to its zero-Covid-19 playbook was a refinement of rules and not a relaxation of controls, dismissing interpretations that the changes were a step towards living with the virus.

Brandishing data that showed cutting centralised quarantine for travellers and close contacts to five days would still catch the vast majority of Covid-19 infections, the officials said a strict attitude towards stamping out infections remains China’s guiding principle.

The changes, which include reining in mass testing and banning local officials from overzealous lockdowns, come from “a better understanding of the virus, and better research and development of vaccines”, National Health Commission deputy head Lei Haichao said at a Saturday briefing.

Still, they did not rule out a further easing of the rules.

When asked about one day shuttering centralised quarantine camps, Dr Wang Liping, a researcher at the Chinese Centre for Disease Control and Prevention, said China’s Covid-19 playbook would continue to be guided by science.

Later, Mr Lei reiterated that the government would “keep advancing in small steps”.

The messaging came as a clear riposte to market euphoria over the 20 new measures to guide Covid-19 control, the announcement of which sent Chinese assets surging on Friday as investors cheered a potential shift away from the virus approach that is exacting a growing social and economic toll. 

Nevertheless, change has come quickly on the ground across China as cities reduced mass Covid-19 testing and released people from quarantine camps according to the new guidelines, even as the national caseload continued to rise. 

Sanya in the southern island of Hainan cancelled a city-wide testing scheduled for Saturday, and instead asked residents to make their own arrangements to get tested once every three days, according to a notice posted by the local government late on Friday.

Fuzhou in the south-eastern province of Fujian suspended daily mass testing in five districts for four days from Saturday, according to an official notice.

China reported that new local cases rose to 11,323 on Friday, after daily infections climbed above 10,000 for the first time since April on the previous day.

Much of the surge came from the southern metropolis of Guangzhou, where new cases jumped to 3,180 from 2,583 on Thursday.

Chongqing in south-western China reported 1,240 new infections, up from 782.

Many local governments also heeded the latest instruction to re-categorise “high-risk” areas that are placed under more stringent mobility curbs.

The national guideline asked the local authorities to narrow the scope of high-risk areas to resident units or blocks, and to remove the “medium” risk category. 

Zhengzhou in central China, for example, released an updated list of high-risk areas, many of which were narrowed to specific building units.

It was not immediately clear whether residents in areas that are no longer categorised as high or medium risk were already released from quarantine.

Guangzhou is taking steps to release from isolation close contacts of Covid-19 victims as the guideline required, local government officials said in a press briefing on Friday. 

Public venues in Beijing are tightening Covid-19 control requirements as an outbreak continues to spread in the city.

An increasing number of venues now require a negative Covid-19 test result generated within the past 24 hours for visitors to enter.

Beijing’s new local infections were unchanged at 114 on Friday from a day earlier.

At the Saturday briefing, officials reiterated that local officials are banned from excessive disruption to people’s lives in the name of Covid-19 control, saying medical services cannot be compromised and crucial transport links must remain running, even in the midst of outbreaks. BLOOMBERG