Dramatic drop in new infections was “expected” in the September simulation
Since October 17, the number of new cases of the new coronavirus per day in Japan has fallen below 500, and on the first of this month, the number dropped all the way down to 86. This is the first time since June 27 last year that the number of new infections has fallen below 100.
In Tokyo, the number of newly infected people had been below 50 for many days, but on the 1st, the number dropped to 9, the first time since May 31 last year that the number was in single digits. The highest number of new infections in Tokyo was 5,908 on August 13 (changed from 5,773 due to correction of a tallying error). More than two months have passed since then, and the number of infected people has decreased dramatically.
In September, this website interviewed Professor Yukio Osawa of the University of Tokyo’s Graduate School of Engineering, who is a member of the Cabinet Secretariat’s “COVID-19 AI/Simulation Project” research and development team, about the “necessity of a third vaccination. Dr. Osawa’s simulation results also showed a dramatic decrease in the number of newly infected people in Tokyo from late October to early November.
Even if the number continues to decrease, is a third vaccine, or booster vaccination, necessary? Will there be a sixth wave in the first place? We asked Dr. Osawa, who insists that “booster vaccination is essential,” how he sees the current situation.
If the booster vaccination is given “eight months” after the second vaccination, the sixth wave is almost certainly coming. There is no doubt about it.
First of all, why did the number of newly infected people begin to decline so rapidly?
“One of the factors is certainly the effectiveness of the vaccine. In my study, when I simulated the situation without including vaccination, the results were disastrous. Of course, progress in vaccination is not the only factor in the decline.
It was on September 13 that the government announced that the percentage of people who had received two doses of vaccine had exceeded 50%. As of mid-August, the vaccination rate was still in the 30 percent range, but since September, vaccination has indeed progressed.
Will the downward trend continue, even if the number of newly infected people in Japan does not reach zero? “Many experts believe that the sixth wave is coming, but some people on the street are asking, “Is it really coming? Some people in the city are asking, “Is it really coming?
“If we don’t get booster shots, the sixth wave is almost certain to come. Additional vaccination is clearly necessary, and based on my simulation results, booster vaccination is effective four months after the second vaccination.
For example, my collaborator, Professor Masaharu Tsubokura of Fukushima Medical University, is currently evaluating the decay of immunity in people who have received two doses of vaccine. If many people return to their original immunocompromised state, the number of infected people will be considerable.
Based on this trend, it would be effective to give the third round of vaccination about four months later, when the antibodies have weakened. The Ministry of Health, Labor and Welfare seems to be thinking of doing it after 8 months, but at that pace, I think a destructive 6th wave will come.
The first round of vaccinations in Japan began in February of this year for healthcare workers and in April for the elderly. The Ministry of Health, Labor and Welfare (MHLW) has indicated that it will offer a third round of vaccinations to those who have completed the first two doses, and that the target population will be those who have been vaccinated for at least eight months. The vaccination is expected to start in December for medical workers, and in January next year for the elderly and people under 65.
“As for the big sixth wave coming after eight months of booster vaccination, researchers other than myself involved in the AI simulation project at the Cabinet Secretariat have shown the same result. Their simulations show that the sixth wave is coming, to some extent, even after six months.
“The UK’s corona countermeasure is a failure case. Japan should not imitate it.
But is it actually possible to give a booster vaccination 6 months after the second vaccination? Dr. Osawa says that the booster vaccination should be effective four months after the second vaccination, which means that elderly people who received the second vaccine in April would have to start the booster vaccination in August, which is no longer possible.
“Under the MHLW’s proposal, booster vaccinations in December would only be available to medical personnel, so my parents, who received their second dose in June, would not be able to receive a third dose six months later for now.”
The results of the study by the Cabinet Secretariat’s AI simulation team are posted on the web. The results of the Cabinet Secretariat’s AI simulation team have been posted on the Web, and the subcommittee and others are probably aware that the researchers commonly agree that eight months is too late for the third dose. So far, however, the results of the researchers’ simulations do not seem to have been reflected in the national policy.
“We don’t know if the Cabinet Secretariat will accept our ideas, but I think eight months from now will be an improvement. The researchers involved in the project are unanimous in saying that eight months is too late.
If it is not possible to set a uniform timing of booster vaccination for all patients, we can leave the timing of booster vaccination to the discretion of medical personnel for those who have some disease or whose immunity is weakened for some reason. I am advocating the effectiveness of doing so.
In a document published on the MHLW website for the “25th Meeting of the Subcommittee on Immunization and Vaccination of the Health Sciences Council” held on October 28, it says, “Based on trends in other countries and the scientific knowledge currently available, the timing of additional vaccinations should be approximately 8 months or more after the completion of two doses of vaccination.
It is unclear which “other countries” the MHLW is referring to, but for example, in the United Kingdom, which became the first country in the world to start full-scale vaccination in December last year, the third round of vaccinations began in mid-September. In the UK, for example, the third round of vaccinations began in mid-September. However, on October 21, the number of people infected in one day exceeded 50,000, and the infection is spreading again.
“I think the problem lies in the timing of the booster inoculations and the way citizens who don’t wear masks interact with each other. I think that the timing of the booster vaccination and the way citizens interact with each other without wearing masks is the problem. The way the UK and other countries have done it is a failure case, and Japan should not do the same. However, even if the number of infected people in Japan decreases so much, the citizens still wear masks properly and live their lives, so we will not be in the same situation as the UK.
The “Vaccine Passport” is expected to have some effect when it is introduced in December.
In Japan, the declaration of a state of emergency and priority measures to prevent the spread of the disease were fully lifted on September 30, and the request to shorten business hours for restaurants was also lifted on October 25. With experts saying that the sixth wave is coming, should everything be lifted before the booster vaccinations begin?
The answer is, “I think it’s both a good idea and a dangerous idea. The rationale for the former is that the number of newly infected people is in a very low state. The former is based on the fact that the number of newly infected people is decreasing very rapidly, and this was verified in a paper I published last year.
However, this does not mean that this will happen 100 percent of the time. Simulations have also shown that if the state of emergency is declared and human contact is reduced by 80% and the number of infected people reaches its peak and then the traffic is restored, the infection will spread twice as much as if the state of emergency is not declared. This shows that declaring a state of emergency can lead to an explosion of infections when people are released.
The number of infected people is low enough now, but the question is how many potential infected people there really are. I think there probably are. Now is the time when the effectiveness of the vaccination is beginning to decline, so it may be dangerous to restore human traffic and interaction.
I guess it’s too early to release them all at once until they’ve had their third dose of vaccine.
By the way, the government’s demonstration tests of “vaccine and test packages,” which certify that a person has been vaccinated or has tested negative for PCR, have started in various places for events, tourism, and restaurants.
In addition to the timing of booster vaccinations, Dr. Osawa has also published the results of a simulation of the introduction of the Vaccine Passport in Japan.
“According to the simulation, if the Vaccine Passport is introduced on November 1st and spread to everyone, it will be very effective. However, in reality, it has not been officially introduced yet.
If the vaccine becomes much more popular in December, we can expect it to be effective to some extent, so we are hoping that this will somehow control the spread of the infection until the booster vaccination starts. In short, we will use a combination of booster vaccinations and vaccine passports. I call this a “strategic cocktail,” analogous to an antibody cocktail.
However, I can’t say that all the wheels are turning well at the moment. The booster vaccination will be available in eight months, and the “vaccine and testing package,” the equivalent of a vaccine passport, is still in the demonstration stage. I don’t think we can rest assured.
With the number of newly infected people decreasing so much, it is easy to feel relaxed. However, Dr. Osawa and other experts have pointed out that the sixth wave is coming. I hope that the new Kishida administration will take the necessary measures to prevent a repeat of the Abe and Kan administrations’ repeated failures in dealing with coronas.
Yukio Osawa is a professor at the Department of Systems Innovation, Graduate School of Engineering, the University of Tokyo. Born in Kyoto in 1968, he received his Ph. He has been in his current position since 2009. He specializes in system design, knowledge engineering, and business science. He specializes in systems design, knowledge engineering, and business science. His research interests include opportunity discovery, innovation markets based on data jackets, and data visualization and valorization.
He is the author of “Future Salesmanship Discovery” (editor and publisher, Diamond Inc.), “Business Chance Discovery Technology” (Iwanami Active Shinsho), “Innovation Idea Technology” (Nihon Keizai Shimbun Publishing Inc.), and “Data Market” (Modern Science Inc.).
Interviewed and written by： Sayuri Saito Photo： Afro