Residents wait in line to get tested for Covid-19 on January 9 in Tianjin, China.

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Hong Kong CNN  — 

Officials in Beijing are on high alert just weeks out from the start of the Winter Olympics, after China’s first local outbreak of the Omicron variant spread from the northern port city of Tianjin to the central province of Henan.

Tianjin, located just 80 miles southeast of Beijing, is testing its entire population of 14 million people after Omicron was detected in at least two local residents Saturday – the country’s first reported community spread of the highly transmittable variant.

The city reported at least 40 positive cases over the weekend, including 24 children, though health authorities have yet to confirm whether they are infected with Omicron.

Tianjin authorities moved quickly to place 29 residential communities under strict lockdown, and ordered citizens not to leave the city unless absolutely necessary. Those who want to to leave must present a negative Covid test taken within 48 hours and obtain approval from their employer or local government offices.

But the virus has already spread far outside the city. State media reported Monday that two more Omicron cases had been identified in Anyang city, Henan province, more than 300 miles from Tianjin.

Genome sequencing of the virus found that it belongs to the same transmission chain as the Tianjin outbreak, according to Henan health authorities. A university student who returned to Anyang from Tianjin on December 28 is believed to have brought back the virus – suggesting the variant has already been spreading in Tianjin for nearly two weeks, at the least.

That is particularly worrying news to officials in Beijing, which is fewer than 30 minutes away from Tianjin by high-speed rail.

In recent months, Chinese authorities have imposed ever more stringent restrictions to curb local Covid flare-ups as Beijing prepares for the Winter Olympics. An Omicron outbreak on the doorstep of the capital just weeks before the Games kick off on February 4 represents something of a nightmare scenario for officials – who are now likely to ramp up efforts to protect Beijing.

“It is impossible for China to return cases to zero before the Winter Olympics, because local outbreaks are springing up one after another,” said Jin Dongyan, a virologist at the University of Hong Kong.

“The only thing Beijing can do is to learn from the experience of the Tokyo Summer Games and hold the Olympics while community transmission is going on in the country,” he said, noting that the event will be held within a tightly-sealed bubble isolated from the local community anyway.

BEIJING - AUGUST 08:  A welcome message is displayed on the stadium roof as drummers perform during the Opening Ceremony for the 2008 Beijing Summer Olympics at the National Stadium on August 8, 2008 in Beijing, China.  (Photo by Ezra Shaw/Getty Images)
14 years ago Beijing held a different kind of Olympics
03:22 - Source: CNN

Beijing and Tianjin share a short border and are closely linked. An estimated 100,000 people commute regularly between the two cities for work as of 2020, according to the state-run Global Times.

In a statement Sunday, the Beijing Center for Disease Prevention and Control advised Beijing residents not to visit Tianjin and those in Tianjin to refrain from traveling to the capital. It also asked commuters between the two cities to work from home. By Sunday evening, train tickets from Tianjin to Beijing could no longer be purchased online.

The center also ordered people who arrived in Beijing from Tianjin since December 23 to report to their residential communities, employers or hotels for health monitoring and Covid tests. Those who came from high-risk areas of Tianjin are required to self-isolate at home.

Keenly aware of the public health risk and political pressure, Tianjin officials convened a video meeting at 1 a.m. Sunday in a show of their resolution to contain the outbreak.

Li Hongzhong, the Communist Party chief of Tianjin, is widely regarded as an ardent supporter of Chinese President Xi Jinping. At the meeting, Li vowed to take “resolute measures” to “make all-out efforts to block the channels of transmission” and fortify Tianjin’s role as a “moat” to protect the capital against the virus.

Party and government organizations, state-owned companies and public institutions were ordered to take the lead in keeping their employees in Tianjin, while checkpoints were set up at the airport, highways, train stations and ports.

All tutoring centers, daycare centers and vocational training centers were closed down, while universities and colleges sealed off their campuses.

Tianjin is considered among China’s foremost cities. It is one of only four provincial-level municipalities directly under the administration of the central government – alongside Beijing, Shanghai and Chongqing.

Tianjin authorities have not ordered a full lockdown that would confine all residents to their homes – the kind that was imposed in the northwestern city of Xi’an last month, which sparked an outcry over food shortages and obstructed medical access.

Such a move would be politically fraught and economically damaging – Tianjin is a major port and economic hub, and a stringent citywide lockdown in the lead-up to the Lunar New Year could risk sparking resentment among residents.

But news about the cases and travel restrictions already sparked panic buying over the weekend, with residents snapping up groceries and other critical supplies at supermarkets.

The Omicron variant is the latest challenge to China’s zero-Covid policy. For months, Chinese authorities have tried to keep it outside the country’s tightly controlled borders through rigorous testing and lengthy quarantine for international arrivals.

Tianjin was the first city in mainland China to detect an imported case of Omicron – in an asymptomatic traveler who arrived from overseas on December 13. Since then, the southern cities of Guangzhou, Shenzhen, Changsha and the eastern province of Zhejiang have all detected imported Omicron cases.

Jin, the expert at the University of Hong Kong, said the Omicron outbreak in Tianjin is to some extent expected, as it is virtually impossible for border controls to be completely watertight against the variant. In Hong Kong, authorities are also rushing to contain an Omicron outbreak introduced by an aircrew member.

Compared to the Delta variant, Omicron poses an even bigger challenge as it spreads faster and is harder to detect, due to its lower viral load, Jin said.

“Even if Tianjin completes its citywide testing, it might not be able to identify all the cases in the city,” he said.