The biggest danger Covid-19 for the Tokyo Olympics is not the thousands of athletes and officials who come from abroad, but if it leads to greater mobility and socialization among local people, according to experts who study the event.
As well public anxiety in Japan it focuses on the 100,000 athletes, trainers, officers and journalists they have began to arrive seven weeks before the games, epidemiologists said the biggest risk was a change in public behavior.
His analysis helps explain why Japan has advanced with the Olympics despite widespread opposition, so Tokyo may limit the public mix if it ultimately decides to hold the games without spectators.
“More than the number of people, that’s how they behave.” That’s the problem, ”said a Japanese health administrator who has seen official epidemiological advice.
Tokyo and other major cities in Japan remain below State of emergency Covid-19, encouraging calls from doctors, business leaders and up to 80 percent of the Japanese public to cancel the Olympics. Slowly, slowly vaccination means that most Japanese are still vulnerable to the disease.
Japan has given at least one dose of vaccine to only 9 percent of its population,
Experts have identified four separate risks to holding the games this summer: Olympic visitors spreading the coronavirus; increased mobility among the Japanese public; stress on medical resources; and the threat of new Covid-19 variants entering the country.
Of these risks, most analysts think the danger of the Olympians carrying Covid is small.
Taisuke Nakata, a researcher at the University of Tokyo, applied a standard epidemiological model to the Olympics. Even with extremely pessimistic assumptions – only half of visitors are vaccinated, none of them respect quarantine and 100 infections are missing from border tests – they have little impact on Japan’s Covid-19 pandemic.
According to the Nakata model, the result of this scenario is an increase of about 15 infections per day a few months later.
“Intuitively, it’s just that the number of Olympic visitors is less than 1 percent of Tokyo’s population,” he said. Since coronavirus is already prevalent in Japan, athletes and other visitors cannot greatly accelerate the pandemic.
In fact, 80 percent of visitors are expected to get vaccinated, and they will enter tight quarantine with Covid-19 testing every day, so its impact on infections in Japan should be minimal.
The most serious threat is that the Olympics will induce a change in behavior by the Japanese public. Tokyo controlled Covid-19 by closing restaurants at 8pm and asking them not to serve alcohol to limit the amount of high-risk socialization.
Filling the stadiums with fans would have the opposite effect. “If the athlete you support wins a gold medal then you will shout with joy and then everyone will say‘ let’s drink, ’” said Shigeru Omi, the doctor in charge of Japan’s Covid-19 response, in testimony to the parliament.
In The Nakata model, increased activity by the Japanese public has risked an increase of 90-120 infections per day in a few months.
“Rather than contact between athletes, or between athletes and regular people, it is clearly much more important to limit the movement of the Japanese public,” Omi said.
The third area of risk is stress on the medical system, both in terms of doctors and nurses needed by Olympian staff, and in the pressure of more coronavirus cases. As a result, Japanese clinicians tend to be more negative about gambling than epidemiologists.
“It will take away doctors from university and city hospitals,” said Satoshi Hori, an infection control expert at Juntendo University in Tokyo. “They are volunteers without pay.” They are currently busy in the hospital, so it will cause a shortage of staff. “
Hori said the Olympics should be canceled. “For a brief event, keeping it in a bubble is practical, but having a lot of events in several places for weeks – can it really be kept in a bubble?” He asked.
The final danger is that a visitor to the games will bring a new Covid-19 variant to Japan. Naoto Ueyama, head of the Japan Medical Union, also speculated that the holding of the games could give birth to a “Tokyo Olympic” strain of the disease.
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However, most of the known variants, such as those first detected in the United Kingdom and India, are already present in Japan, although a recent variant found in Vietnam is not. If the Covid-19 variants had not arrived in Japan, the additional risk posed by the Olympics would have been much higher.
Putting all the risks together, Japan is thinking about how to manage the Olympics rather than going ahead, the health official said. “We did a lot of sporting events from sumo to baseball during Covid-19. We had the experience of keeping the coronavirus at current levels without a hard block.”
Unless the government loses its nerve in recent weeks, Japan will soon try to repeat the trick while hosting the world’s biggest sporting event.