As COVID-19 cases tied to Tokyo Olympics rise, experts warn of 'worrying' situation on the ground

COVID-19 cases among Olympic delegates are on the rise and roughly 15 per cent of those staying on site are unvaccinated, prompting warnings from medical experts about potential ripple effects if the world's largest sporting event doesn't clamp down on virus transmission.

Set to begin on Friday with the opening ceremony, the Tokyo Olympic Games were touted as safe and secure by organizers, but have so far been plagued by infections among athletes, hotel workers, and others involved with the event — and those participating have not been required to get a vaccine.

At least 67 cases have been detected among those accredited for the Games since most athletes and officials began arriving on July 1, officials said on Tuesday. The head of the Tokyo organizing committee didn't rule out cancelling the event entirely if cases began to spike.

"You're now introducing risk factors from elsewhere," Nitin Mohan, a Toronto-based physician-epidemiologist and public health consultant, told CBC News.

"Somewhere there will be a breaking point."

Just last week, International Olympic Committee (IOC) president Thomas Bach said tight protocols at the Games would leave "zero" risk of participants infecting residents in Japan, which is experiencing a spike in cases among its largely unvaccinated population.

But Kenji Shibuya, the former director of the Institute for Population Health at King's College London, recently told Reuters the actual conditions on the ground were "totally opposite," with the potential to fuel clusters of infections in the village accommodations or among locals.

"It's obvious that the bubble system is kind of broken," said Shibuya.

WATCH | COVID-19 fears rise as Tokyo Olympics get closer:

Vaccination not required to participate

Concerns around the Olympics, which were postponed for a year during the pandemic, have recently grown as COVID-19 case counts in much of the world are surging because of more-contagious variants and low vaccination rates in many countries.

In Japan, the seven-day average for new daily cases is now more than 3,000, and only a little over 20 per cent of the country's population is fully vaccinated.

"It's worrying if the right precautions and protocols are not in place," Mohan said.

The IOC did implement strict testing regimes and regulations, including spectator-free venues and a playbook encouraging delegates to avoid physical contact.

But according to those guidelines, athletes "will not be required to have received a vaccine in order to participate in the Games."

On Monday, the IOC's Bach said 85 per cent of Olympic Village residents have been either vaccinated or are immune to COVID-19, which leaves around 15 per cent unprotected.

That's concerning, according to Mohan, who said even professional athletes have reported long-lasting health impacts following coronavirus infections.

"Allowing unvaccinated athletes into an environment where they could possibly acquire the virus is dangerous," he said.

Some Olympic athletes are staying unvaccinated by choice, including U.S. swimmer Michael Andrew, who made headlines for refusing to get a shot because he feared it would interfere with his pre-competition training.

"We're pretty certain that if you test people and you mitigate by masking and ventilation and distancing and all that kind of stuff, the risk is actually pretty low … but if you have gaps in that, that's when you will have problems," said Dr. Andrew Morris, an infectious diseases specialist with Sinai Health System in Toronto.

WATCH | IOC's Bach says 'zero' risk of COVID-19 spreading from participants:

Games may avoid 'total disaster'

On Tuesday, Toshiro Muto, the chief of the Tokyo 2020 organizing committee, didn't rule out cancelling the international event if COVID-19 cases kept rising.

"We will continue discussions if there is a spike in cases," he told a press conference.

So far, all signs point to the infections continuing.

Four athletes have tested positive so far — out of the 11,000 competitors expected to stay in the Olympic village — while entire teams have been impacted by possible exposures.

In one instance, the first six members of Brazil's judo team who had landed in Tokyo were forced into isolation after COVID-19 cases were discovered among the staff at a hotel where they are staying in Hamamatsu, southwest of Tokyo, while waiting to compete.

"Tokyo is undergoing a surge, and to bring in people from all over, with all the different challenges they have, into a country and a city that's already having its own challenges — that's definitely not a public health move," said Morris.

Still, if the Games can maintain fairly high restrictions, he said the event should be able to avoid becoming a "total disaster."

Some infections among participants are to be expected, Morris said, but the chance of the Olympics fuelling a mass-transmission superspreader event is unlikely.

"If there is, it's going to be [because of] breaches of protocol in the Athletes' Village," Morris said.

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