Some countries have resorted to dropping mask mandates, opening borders and schools as the Omicron variant sweeps across the globe, but China is standing firm on its zero-Covid policy – in place since the pandemic first broke out. China’s two years of persistence have meant relatively low death rates as each fresh outbreak is met with swift responses, including rigorous testing and contact tracing, area or citywide lockdowns, and travel curbs. Omicron has brought Hong Kong to its knees. How did it all go wrong? The southern city of Baise on the Vietnam border was the latest to employ this strategy – updated in the face of more infectious coronavirus strains like Omicron – to “dynamic zero” where the aim is to cut the transmission chain rather than pursue zero cases. The city acted fast after identifying an Omicron case on February 4 – a returnee from the tech hub of Shenzhen bordering Hong Kong. Mass testing in the patient’s county began the next day, with close and secondary contacts told to isolate. The city of 3.6 million was then placed under strict lockdown two days later, after the mass testing revealed close to 100 cases. The measures appeared to have slowed transmissions, with just two cases recorded on Tuesday and authorities announcing the chain of infection had been cut. Most city areas lifted lockdowns and reopened transport links on Tuesday. The strict test-isolate-quarantine-lockdown regimen has been repeated several times across the country since the early days of the pandemic. As parts of Baise opened up on Tuesday, Manzhouli in northern Inner Mongolia ordered area lockdowns as it launched citywide Covid-19 testing after detecting five positive cases. But health successes exact a cost in terms of disruption of daily lives and suspension of personal rights. This model cannot be copied by all societies, even if they too are aiming for dynamic zero, such as Hong Kong. “Combining lockdown with repeated mass screening is more suitable under the mainland social system with its strong community infrastructure support,” Hong Kong respiratory disease expert Dr Leung Chi-chiu said. “As the Hong Kong scenario is rather different , we need to use our own methods to slow the spread of the virus and speed up cutting of transmission links.” This comes as Hong Kong struggles to beat a surging fifth wave of Covid-19, with average daily cases topping 1,431 cases for the past week, after just single-digit daily increases through most of last year. On Wednesday, Hong Kong recorded 4,285 new infections, and 7,000 more preliminary-positive infections. The Centre for Health Protection said all but 21 of Wednesday’s cases were locally transmitted, with the city’s tally of confirmed infections rising to 30,955. The city’s health care system has been overwhelmed, forcing the government to give up on isolating all positive cases, as it prioritises hospital space for children, the elderly and seriously ill. Officials shortlist 3 sites for construction of Hong Kong mega-hospital Leung blamed the explosive situation on a “delay in action and lack of social consensus”, with daily cases overwhelming response capacity and facilities. “Prompt isolation of detected cases is the key and necessary tool to cut a transmission link,” he said as cases surged last week, adding that targeted testing and prompt isolation could be reinforced through community mobilisation of suitable manpower and facilities, and strong central support. Public restraint would also work better than lockdowns, he noted. “If social consensus can be achieved, voluntary efforts to stay home can be tolerated much longer than indiscriminate lockdown, to allow sufficient time for elimination of all local infectious sources,” Leung said, citing Taiwan’s success in controlling the Alpha strain this way last year. Meanwhile, commentaries in Xinhua and People’s Daily last week urged Hong Kong to stick to the “dynamic zero-Covid” strategy, saying a “live with the virus” approach was not suitable for the city. Living with zero Covid in China, 2 years and counting Zeng Guang, former chief scientist at the Chinese Centre for Disease Control and Prevention and a senior adviser to Beijing on coronavirus control, said Hong Kong could still achieve “dynamic zero-Covid” and this approach was in the public’s best interests, as he highlighted the city’s past success on this. “There is still hope for Hong Kong to achieve zero-Covid … experimenting with [different] policies will benefit future opening. A rushed opening benefits neither the government nor the public,” Zeng said on Saturday. Hong Kong, as a special administration region, had more freedom on its Covid-19 policy, and there was no doubt that Beijing would offer whatever support needed, he said. He also suggested the city consider setting up mainland-style makeshift hospitals for mild cases, to ease the pressure on existing facilities. Zeng said Beijing was still weighing the pros and cons of opening up national borders, but that depended on several factors, including whether Omicron was the last variant of the coronavirus. He said China might loosen restrictions if it worked for other countries, but was in no rush to do so, as it did not have to tackle the huge economic or social pressures faced by the United States or Europe.