China has built a 5,000-room quarantine centre for overseas arrivals. It could be the first of many

The Guangzhou quarantine facility for foreign arrivals is comprised of rows of three-story buildings and has 5,000 rooms. (Chinatopix/AP)

When it comes to keeping COVID-19 at bay, few countries seem willing to go as far as China.

As countries around the world reopen borders and loosen coronavirus restrictions, Beijing is doubling down on its zero-COVID strategy. The latest example: a US$260 million, 5,000-room quarantine facility for incoming travelers set to open in the southern metropolis of Guangzhou in the coming days.

Comprised of rows of three-story buildings topped with gray roofs in traditional Chinese style, the massive complex spans an area the size of 46 football fields and took less than three months to be built from scratch on the outskirts of the city.

It will replace designated hotels located throughout Guangzhou to quarantine Chinese and international travellers arriving from overseas -- a move aimed at reducing residents' exposure to imported cases.

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Travellers will be transferred on buses directly from the airport, and confined to their rooms for at least two weeks. Each room is fitted with a video chat camera and an artificial intelligence-powered thermometer, with three meals a day delivered by robots -- all designed to minimize direct contact with staff members.

"It's arguably the most state-of-the-art quarantine center in the world, if you will -- very high tech, very sophisticated," said Yanzhong Huang, a senior fellow for global health at the Council on Foreign Relations.

The Guangzhou International Health Station -- as it's officially named -- is the first of its kind in China. But experts say it could be the first of many as the Chinese government intensifies its uncompromising, zero-tolerance strategy toward the coronavirus.

Already, the manufacturing hub of Dongguan, about an hour's drive from Guangzhou, is building its own "international health station" with 2,000 rooms. Further south, the technology hub of Shenzhen is also planning for such a facility.

"This is not just a stopgap measure. (Chinese leaders) hold the view that this pandemic is going to take a while to end, and China is going to continue this strict control of its borders," Huang said. "Facilities like this serve as a way to institutionalize the zero-tolerance strategy."

For more than 18 months, China has closed its borders to most foreigners. Those few who are allowed to enter, as well as returning Chinese citizens, are required to undergo at least two weeks of mandatory hotel quarantine, followed by at least another week of centralized quarantine or home isolation -- including those who are fully vaccinated.

But the virus has repeatedly breached China's defenses. In May, the highly infectious Delta variant caused an outbreak in the southern province of Guangdong, including in Guangzhou and Shenzhen. At that time, Guangdong was receiving 90% of all overseas travelers entering China, with about 30,000 people quarantined in its 300 centralized facilities on a daily basis, according to a provincial health official.

By late June, Guangdong had contained the outbreak -- but authorities decided existing measures were not enough to shut the virus out. Zhong Nanshan, a top public health adviser to the government, told state media that Guangzhou would build a centralized quarantine facility for all overseas arrivals to enforce stricter rules.

The project kicked off quickly, with more than 4,000 workers assigned to the construction site. The facility was completed earlier this month and a first batch of 184 medical staff moved in last week to prepare for its official launch.

They face a tough job ahead. The complex is designed as a bubble to be isolated from the rest of the city -- meaning not only travelers, but also workers will be placed under effective lockdown. Medical staff will work for 28 days at the facility, go through a week of quarantine themselves, and another two weeks of home quarantine before they're allowed to go outside, an official told the Guangzhou Daily newspaper.

China's move to tighten quarantine measures for overseas arrivals comes as a growing list of countries open up. Last week, the United States announced it would ease travel restrictions on all fully vaccinated foreign visitors starting in November.

But on Chinese social media, calls are growing for authorities to lengthen quarantine for overseas arrivals. Many blamed Chinese travelers returning from abroad for bringing the virus to China, especially following the latest outbreak in the southern province of Fujian.

Initially, experts advising the government identified a man who returned from Singapore more than a month ago as the likely source of the outbreak, despite him having completed 21 days of quarantine on arrival, during which he tested negative for the virus a total of nine times. The average incubation period for the Delta variant is about four days.

Later, health experts walked back that theory, saying the man was likely to have picked up the virus during centralized quarantine instead. But the clarification did little to calm online calls for tougher quarantine requirements.

China's move toward stricter quarantine comes despite the country making huge strides in its vaccination drive. Earlier this month, officials announced that 1 billion people had been fully inoculated with domestically made vaccines, accounting for 71% of China's 1.4 billion population -- a rate higher than many countries that have opened their borders.

Guangzhou's new quarantine facility will open just in time for the China Import and Export fair, which begins October 15. The biannual event, also known as the Canton Fair, is China's largest trade exposition, typically attracting tens of thousands of companies from around the world.

Having been held online so far during the pandemic, next month marks a real-world return for the trade fair -- but attendance will be limited to exporters and buyers already based in China.

Nevertheless, authorities in Guangzhou have stepped up quarantine requirements for all overseas arrivals, raising their mandatory quarantine from 14 days to 21 days.

Huang, the expert at the Council on Foreign Relations, says despite its enormous size, the facility would likely not be big enough to hold all foreign arrivals. "Just think about it. One international flight typically carries 300 people. They all need to be quarantined and stay at least 21 days. It's going to fill up quickly," he said.

COVID CATS' DEMISE

When Liu, a 28-year-old in China's Harbin city, tested positive for COVID-19 last week, she left enough food and water at home for her three cats before entering hospital quarantine, she told state-run outlet Beijing News. She trusted that community workers would come by her apartment to care for her pets while she was away.

Instead, when the cats also tested positive for the virus, the workers euthanized all three without her consent, according to Beijing News, which only identified Liu by surname.

Liu was told Monday her cats' samples had tested positive for the virus, and that putting them down was the only option because there is no available treatment for animal infection. Liu pushed back and refused to sign a consent form for euthanasia, according to Beijing News. By the next day, the three cats had been put down anyway.

Without treatment, the cats would continue carrying the virus, and the household would be an infected space even after Liu returned from quarantine -- risking another outbreak, an unnamed community worker told Beijing News.

CNN reached out to officials in Nangang district, where Liu lives, who said they did not know about the matter.

Animals in different countries have contracted COVID-19, including domestic pets, zoo animals and farmed species, with humans the primary source of these infections.

But although scientists say COVID-19 likely originated in animals before becoming widespread among humans, there is no evidence that animals are playing a significant role in the spread of the virus to people, according to the U.S. Centers for Disease Control and Prevention.

Liu's story went viral on the strictly censored Chinese social media platform Weibo, with a related hashtag gaining more than 14 million views. Users were divided, with pet owners and sympathizers outraged, while others viewed the euthanasia as a sensible choice during the pandemic.

"The pandemic situation is so serious abroad, but have you ever heard of a report that even one pet has been euthanized?" one Weibo user commented. "For families with pets, pets are family. Why [are we doing this]?"

"I don't understand why people are criticizing the country [authorities]," another user wrote. "In fact, the treatment of COVID-19 patients was provided by the state with a lot of money and effort, and medical staff are also at risk of infection ... I don't understand why everyone asks the country to spend so much manpower, materials and financial resources on pet treatment."