The head of the World Health Organization said Wednesday it is not possible to reduce the risk of coronavirus to zero at the Tokyo Olympics, which will open later this week, and the success of the games should be judged on how well infection cases are handled.

As uncertainty remains over whether the Olympics can be held safely, Chile's national Olympic committee said a taekwondo athlete will withdraw after testing positive. It is the first known time an athlete has cited a COVID infection as a reason for pulling out of the games after arriving in Japan.

File photo shows WHO Director General Tedros Ghebreyesus. (Kyodo)

Giving a speech at a meeting of the International Olympic Committee in Tokyo, WHO Director General Tedros Adhanom Ghebreyesus said anti-virus measures the organizers have drawn up with the advice of his organization will be "put to the test."

"The mark of not zero risk. I know that some cases have already been detected," he said. "The mark of success is making sure that any cases are identified, isolated, traced and cared for as quickly as possible and onward transmission is interrupted."

The Tokyo Olympics will open Friday following an unprecedented one-year postponement, but the organizing committee has already reported 79 infections, including four announced by municipalities hosting athlete training camps, since the beginning of this month among people connected with the games.

As some Olympic competitions began Wednesday, the Tokyo metropolitan government reported 1,832 new COVID-19 cases, marking the highest daily figure since mid-January.

On that day, the committee logged eight new cases, including an athlete from overseas who was not staying at the athletes' village. An official later identified the athlete as a female taekwondo competitor from Chile.

According to Chile's national Olympic committee, the athlete, Fernanda Aguirre, will not be able to compete at the Olympics because she will be required to isolate for 10 days or more.

A Czech table tennis player was also found to have been infected, according to the International Table Tennis Federation, while Dutch skateboarder Candy Jacobs, who was set to compete in the women's street event on Monday, said on Instagram that she has tested positive for the coronavirus.

"I am heartbroken," Jacobs said in an Instagram post. "Unfortunately I was tested positive for COVID-19 this morning, which means my Olympic journey ends here."

"I am feeling healthy and have done everything in my power to prevent this scenario," she said. "Luckily we've been following the protocols so my fellow skateboarders still get to shine bright."

Of the eight cases reported by the committee, the only case confirmed at the village was a person who had come into close contact with a Czech beach volleyball player who tested positive for the virus earlier this week. The player had 12 close contacts, the committee said.

In his speech, the WHO head said, "It's my sincerest hope that (anti-COVID measures) succeed not only for the sake of the games themselves and the safety of the athletes, trainers and officials, but as a demonstration of what's possible with the right plans and the right measures."

Tedros later met with health minister Norihisa Tamura to discuss international cooperation in the realm of medical and health care amid the pandemic.

He told the minister in Japanese that he "respects" and "appreciates" the host country's efforts to host the Olympics.

Members of the Australian softball team are briefed about taking COVID-19 antigen tests upon arriving at Narita airport near Tokyo on June 1, 2021. The team will take part in a training camp in Gunma Prefecture, eastern Japan, ahead of the Tokyo Olympics starting in July. (Kyodo) ==Kyodo

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