Chinese officials said Thursday they were ready for coronavirus outbreaks inside the Winter Olympics bubble, with plans in place to send symptomatic athletes to designated Beijing hospitals.

February’s Olympics are set to be the most restrictive mass sporting event since the pandemic began, with international spectators banned and all participants required to stay inside a closed-loop system.

“There will definitely be infections and there could be a chance of a small-scale cluster outbreak happening,” said Beijing Olympics virus control official Huang Chun at a briefing, adding that the large number of people involved will have a “very high risk of transmission”.

“There will be a certain number of positive cases” another organising committee official, Han Zirong, said. “This is a high probability event.”

China — where Covid-19 was first detected — has slowed new cases to a trickle, implementing a strict “zero-Covid” strategy involving tight border restrictions, targeted lockdowns, lengthy quarantines and population tracing technology.

Even a single case can lead to a swift imposition of curbs, and officials deemed to have failed at controlling Covid-19 are often sacked.

Hosting a high number of foreigners for the Winter Olympics remains a high-risk endeavour for China’s leaders.

In addition to mandatory vaccinations before landing in China, all athletes and personnel inside the bubble must undergo daily virus testing and health monitoring.

Officials strongly encouraged athletes to get a booster jab due to the global spread of the Omicron variant.

They also provided guidelines for the limited number of domestic spectators.

“We encourage clapping to encourage athletes and don’t recommend (spectators) take their masks off to sing or shout,” Han said.

Athletes who test positive for the virus cannot participate in the Games.

Asymptomatic patients will be sent to on-site quarantine facilities and patients with symptoms will be sent to hospitals in Beijing and Zhangjiakou designated for treating Covid-19 patients, said Huang.

Wards for treating athletes’ medical issues were set up at four Beijing hospitals, as well as a total of 88 on-site treatment stations at the three Olympic competition venues, said Beijing health commission official Li Ang.

Medical treatment protocols were placed under harsh scrutiny during the Winter Olympics Test Events in October, when a Polish luge athlete who was severely injured in a training accident criticised the track team for showing “great incompetence”.

Beijing 2022 organisers and luge officials launched an investigation into the incident.

During the Test Events, three athletes tested positive for Covid-19.

Officials said that the cases were “all handled quickly and effectively, and the transmission and spread of the virus did not occur”.

“The Winter Olympics and Paralympics must firmly execute the Chinese government’s virus prevention and control principles and requirements,” said Han.