More residents in Shanghai are showing up sick, as more than half a dozen rounds of mass tests found the Covid-19 disease lurking among family members cloistered in locked-down homes across the city of 25 million people.

Symptomatic cases rose by 20 per cent to a record 3,200, out of 23,072 infections, according to data of the previous 24 hours released on Friday. That brought Shanghai's total to 303,000 cases since March 1, of which nine patients - unvaccinated, elderly residents from 70 to 93 years - were in "severe" conditions due to their underlying ailments.

"Transmissions within households are currently the main cause of the sporadic spread of the Omicron variant in Shanghai," said Wu Huanyu, a deputy director of the Shanghai Center for Disease Control and Prevention (CDC), during a Thursday online press briefing, adding that contaminated food deliveries have exacerbated the "intra-family" infections.

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Shanghai's authorities earmarked 140 billion yuan (US$22 billion) of tax breaks, cash rebates, rental exemptions and financial incentives to survive, as a citywide lockdown since April 5 has brought China's financial and commercial centre virtually to a standstill.

An area in Shanghai's convention centre-turned makeshift hospital was disinfected on April 14, 2022. Photo: Xinhua alt=An area in Shanghai's convention centre-turned makeshift hospital was disinfected on April 14, 2022. Photo: Xinhua>

Chinese Vice-Premier Sun Chunlan, stationed in Shanghai since April 2 to oversee the anti-pandemic work, instructed local authorities on Thursday to close any "loopholes" in the city's work, after the Chinese president doubled down on his government's pursuit of a dynamic zero-Covid goal.

"Concrete and strict measures must be taken, and a new action plan must be made, as we aim to achieve the zero-Covid goal as early as possible," Sun said on Thursday, according to a Shanghai government statement. "Loopholes in the antivirus measures should be targeted and swiftly closed with strengthened efforts."

Staff members of the online grocery platform Meituan Maicai sort and pack ordered groceries in east China's Shanghai, April 12, 2022. Photo: Xinhua alt=Staff members of the online grocery platform Meituan Maicai sort and pack ordered groceries in east China's Shanghai, April 12, 2022. Photo: Xinhua>

The total infections in Shanghai fell by almost 17 per cent from the record 27,719 cases a day earlier. No death has yet been attributed in Shanghai to the current outbreak, which has surpassed the sum of the previous two years since Covid-19 was first reported in China.

Nationwide, total cases slid from 29,317 a day earlier to 24,166, mostly centred around Shanghai, according to the data released on Friday. Guangdong province in southern China added 41 cases, 22 of which showed symptoms. Jilin province in northeastern China, near the border with North Korea, added 516 infections.

Daily new infections kept surging even after a citywide lockdown was imposed on April 5. Single-day caseload rose to an all-time high for 12 times over the past 14 days, staying above 20,000.

Sun instructed local officials to conduct more mass tests and transfer infected people to quarantine sites as quickly as possible.

At least seven rounds of citywide mass tests on all 25 million residents have been conducted between April 3 and 13, where people in "lockdown zones" - residential compounds with at least one infection over the past seven days - are still subject to daily nucleic acid or antigen tests. Shanghai has yet to announce a time table for lifting the citywide lockdown.

"A prolonged lockdown will eventually cripple the economy and lead to the collapse of businesses," said Wang Feng, chairman of Shanghai-based financial services group Ye Lang Capital. "It is time for policymakers to study how to resume production and commerce."

But the incentives would not be enough to bail thousands of small companies out, Wang added.

The lockdown confined all residents to their homes. Banks, factories, the local stock exchange, the airports and seaports that have kept operating to keep the very heart of China's economy beating are functioning in "closed loops", where workers are required to sleep on-site to ensure zero contact with outsiders.

Since most workplaces are unable to accommodate every employee, factories and transport hubs have had to operate at reduced capacity. The effects are spilling over to the surrounding provinces of Jiangsu, Zhejiang and Anhui, crippling one of the world's most vital supply chains.

Nio, with a factory in the Anhui provincial capital of Hefei, halted its assembly of electric cars for five days, as its supply of components had been disrupted in Jiangsu, Shanghai and Jilin province in northeastern China. The Shanghai-based carmaker said on Friday that production had resumed.

This article originally appeared in the South China Morning Post (SCMP), the most authoritative voice reporting on China and Asia for more than a century. For more SCMP stories, please explore the SCMP app or visit the SCMP's Facebook and Twitter pages. Copyright © 2022 South China Morning Post Publishers Ltd. All rights reserved.

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