[Details] 3 years since confirmation of new corona infection Infection status How is the virus trending?

It has been three years since the first infection with the new coronavirus was confirmed in Japan.

How has the infection of the new coronavirus changed in the last three years, and what kind of mutations have occurred?

And how will corona measures change after this?

Summary.

Accumulated 31 million people infected in 3 years

The new coronavirus was first confirmed in Japan three years ago on January 15, 2020.

According to the Ministry of Health, Labor and Welfare, a cumulative total of 31 million people have been infected so far, and 62,000 people have died.

Among them, the number of infected people has increased explosively, with about 29.74 million people from the beginning of last year until the 16th of this month, when the Omicron strain spread, accounting for about 95% of the three years in just over a year.

fatality rate significantly reduced

The fatality rate, which is the ratio of people who died to the number of infected people, has decreased significantly over the past three years due to advances in treatment methods and vaccination.

The mortality rates so far have been analyzed and summarized by duration of the wave of infection.

▽ 5.34% in the first wave from January 2020, when the first infection was confirmed in Japan.

▽The second wave in the summer of that year was 0.93%, partly due to advances in treatment methods for severely ill patients.

▽ In the third wave of infections that spread rapidly after the beginning of the year (2021), the medical system was strained, and it rose again to 1.82%.

▽Furthermore, 1.88% in the 4th wave in the spring of the year before the spread of the alpha strain, the first mutated virus confirmed in the UK.

▽ In the summer of 2020, the delta strain spread, and in the 5th wave, which spread the infection even more, even among relatively young people, some people became seriously ill and died, while the number of infected people with mild or no symptoms increased. also increased, resulting in a fatality rate of 0.32%.

▽After the 6th wave from the beginning of last year, when the highly contagious Omicron strain spread, the infection spread on a different scale than before, and the number of deaths increased, but the number of infected people increased even more. is an order of magnitude larger, and the fatality rate is 0.17% in the sixth wave.

▽ It was even lower at 0.11% in the 7th wave last summer.

Experts say that the mainstream of infections has changed to the Omicron strain, and many people, especially the younger generation who do not have pre-existing illnesses, have mild symptoms, and the percentage of people who develop severe symptoms due to vaccination has decreased. It is said that it is in

▽ However, in the 8th wave, which is still ongoing, the number of deaths has increased rapidly since the beginning of this year, with the number of deaths reaching a record high every day, and the fatality rate was 0.18% as of the 16th.

Regarding the fact that it is higher than the 7th wave, experts say that since the fall of last year, the method of counting infected people has changed, and while it is possible that not all infected people have been counted, the number of people who die is almost accurate. I point out that what is being reported may have an impact.

Mutant strains continue to be a “cat-and-cat game”

The new coronavirus has been mutating repeatedly for three years since it began to spread, and even now there are concerns about the emergence and spread of new mutated viruses that are highly infectious.

The first confirmed infection in Japan was the same type of virus found in Wuhan, China, but since the spring of 2020, the virus that spread in Europe has expanded in Japan due to mutations.

After that, a mutated virus with increased infectivity emerged and flowed into Japan, and since the spring of 2021, the ``alpha strain'' found in England, and since the summer of 2021, the ``delta strain'' found in India. The spread of "stock" spread, and the medical system was strained one after another with patients becoming severely ill.

Since the beginning of last year (2022), the highly contagious Omicron strain, first reported in South Africa, continues to dominate the country.

After the spread of the Omicron stock type "BA.1", "BA.2" has become mainstream since last spring.

Compared to previous mutated viruses, the Omicron strain has a lower rate of severe disease, especially among younger generations, but the speed of infection spreads much faster, and more people are becoming infected, so some people die. There are many.

And even among Omicron strains, mutations in the direction of evading immunity have been repeated, and since the summer of last year, "BA. The percentage of "BQ.1" is increasing.

Furthermore, "XBB.1.5", which may be more infectious, is spreading in the United States and has been detected in Japan.

Professor Kei Sato of the Institute of Medical Science at the University of Tokyo, who specializes in virology, said, "Even if a vaccine is made, the cat-and-mouse game continues, with mutant strains appearing and escaping. The 'XBB' strain is the least effective against neutralizing antibodies. , I get the impression that the way we deal with mutant strains has entered the next phase.There is no end to the new coronavirus, and we have entered a stage where we need to discuss how to allow the epidemic. We have to find a landing point through meaningful discussions."

Medical site ``The pressure remains the same every time a wave of infection comes''

At hospitals that have been responding to the spread of infection since the beginning, the beds for corona patients are almost full even in the current eighth wave, and for three years, the situation has been repeated with each wave of the spread of infection.

At Minamitama Hospital in Hachioji, Tokyo, while responding to emergency patients who need hospitalization 24 hours a day, an outbreak occurred on the cruise ship Diamond Princess, which entered the port of Yokohama in February 2020. We have received new corona patients.

Since then, the hospital has secured 23 beds, or 14% of its 170 beds, exclusively for corona patients, and has treated up to moderately ill patients. .

Until around the time of the "fifth wave" of summer last year, many hospitals in the surrounding area were hesitant to accept patients due to the risk of infection, so even after recovering from the coronavirus, patients continued to be hospitalized without being able to find a transfer destination. And the situation continued to fill up the hospital beds.

After that, after the "sixth wave" from the beginning of last year, when the Omicron strain spread, the number of patients with severe symptoms of pneumonia decreased. As a result, more corona patients than the number of beds secured are hospitalized, and general medical care continues to be affected.

Even in the current "8th wave," the corona wards have been filled since the beginning of last month, and some of the other wards have been closed to secure beds, making it difficult to accept general emergency patients. The acceptance of emergency patients, who are responding to more than 10%, has remained at about half since the beginning of the year.

Even so, the hospital received a series of requests to accept patients, and even after telling the fire department that there were no beds available, ambulances arrived, and doctors had to respond by providing initial treatment. it is continuing.

Deputy Director Yutaka Seki said, "At first, I had a strong sense of crisis because I didn't know what the nature of the virus was. We must continue to take infection control measures, but we need to revise our maximum measures and put our heads together so that we can shift to a system that accepts more patients. I think," he said.

Public Health Center ``It is very difficult to continue to respond 365 days a year''

Public health centers, which have been responding to the spread of infection since the beginning, have been under pressure for the past three years, such as grasping the total number of infected people and adjusting the hospitalization of patients.

In September last year, the total number of cases was simplified and the work was greatly reduced, but with the "eighth wave" of infections, work such as hospitalization adjustment has increased, and the staff has no choice but to respond without rest on weekends. it is continuing.

Public health centers have been monitoring the total number of infected people, monitoring their health, and adjusting the hospitalization of patients when they are infected with the new coronavirus. I was also busy with tasks such as telephone consultations for certain people and delivering samples of people suspected of being infected to testing institutions.

After that, the transportation of specimens was outsourced to private carriers and delivered to testing institutions, but after the "third wave" in the beginning of the year, the number of infected people surged, and medical institutions that accept patients were searched. Hospitalization arrangements were difficult, and even those who needed hospitalization had to wait at home one after another, and staff were busy with tasks such as checking their health conditions.

According to the Kita Ward Public Health Center, only the elderly and other people with a high risk of becoming seriously ill were required to report an outbreak last September, and the total number of infected people was simplified, so the workload of the public health center was reduced by about 70%. , it means that the tightness has been reduced.

However, with the current "eighth wave," there has been an increase in health management tasks, such as coordinating patient hospitalization and calling and visiting patients recuperating at home. It means that we are responding with a system of 20 people.

Hideo Maeda, director of the Kita Ward Public Health Center, said, "The explosive increase in the number of infected people made the health center's business so strained that it could be said that it was bankrupt.Amidst this situation, dispatched staff were asked to join in emergency situations, and work was transferred to the private sector. It has become possible to establish an effective personnel system by outsourcing to institutions, etc. In addition, communication has been greatly strengthened as a result of having to share information with local medical institutions in real time. However, it must be said that it is extremely difficult for public health center staff to continue to provide support 365 days a year for the past three years."

What will happen to the positioning from "class 2 equivalent" to "class 5"?

What will happen to the new corona infection measures in the future?

At a press conference on the 16th, Chief Cabinet Secretary Matsuno said, "So far, we have focused on scientific knowledge and evidence, and have taken measures based on the infection status and the opinions of experts. Currently, we are trying to balance prevention of the spread of infection and socioeconomic activities. We are working to enable socio-economic activities to be as close to normal as possible while taking the necessary measures."

In the spring of this year, the government will review the position of the new corona under the Infectious Diseases Act from "equivalent to type 2", which can take strict measures, to "type 5", which is the same as seasonal influenza. .

Regarding this, Chief Cabinet Secretary Matsuno said, ``We have just started discussing this at the Ministry of Health, Labor and Welfare council, and we will continue to consider it based on the infection status, scientific knowledge, and discussions of experts.''

Chairman Omi ``We need discussions with a sense of convincing and empathy''

Shigeru Omi, chairman of the Government Subcommittee, spoke about how to deal with this virus in the future.

"From now on, the most important thing is to 'move the economy and society' while at the same time 'maintain the medical system.' It is necessary to achieve these two goals at the same time. I think it is necessary to take measures that are based on the characteristics of the current coronavirus to determine which is the best way to achieve these two goals. Rather than simply coming to a conclusion, we need deep discussions on how to think about it.

[Click here for details] Interview with Chairman Omi How is the 8th wave of the new corona?

From now on?