New Corona and Japan What's happening now January 6th, 18:52

The first confirmed infection with the new coronavirus in Japan was on January 15, last year.

At that time, it was called "new pneumonia".

It's been a year since then.

Japan has experienced three major "waves of infection" (although it is still in the middle of the "third wave") and is about to enter its second state of emergency.

I tried to summarize what is happening now and what to do.

(Reporter, Ima Mitani, Naoki Azuchi, Faculty of Science and Culture)

What's happening now?

On January 5, a government subcommittee on measures against the new coronavirus made urgent recommendations.

In this report, he analyzed the current infection situation as "the situation has become easier to spread not only in metropolitan areas but also in rural areas, and the clusters have diversified." If the infection situation in the metropolitan area does not subside, there is a risk that the infection will spread rapidly nationwide. "

In fact, for the Tokyo metropolitan area, especially Tokyo, Saitama, Kanagawa, and Chiba prefectures, it is necessary to take measures equivalent to the most serious "stage 4" of the four stages indicated by the subcommittee. It is pointed out that it has become.

The four stages presented by the subcommittee are:

▽ Stage 1: Sporadic outbreak of infected people and stage where there is no particular problem in the medical care provision system

▽ Stage 2: The number of infected people gradually increases.

Stage

where the load on the medical care provision system accumulates

▽ Stage 3: The number of infected people increases rapidly.

Stages

where measures are required to avoid major obstacles to the medical care provision system

▽ Stage 4: Stages

where measures are required to avoid

explosive spread of infection and serious malfunction of the medical care provision system

Stage 4 equivalent measures The stage where is needed is a very serious situation that is approaching the entrance to the "explosive spread of infection".

At this stage, the subcommittee has had no choice but to consider a state of emergency.

Second state of emergency

So how is the second state of emergency different from last year's declaration?

The subcommittee emphasizes that "what we have learned" should be put to good use.

The new coronavirus was still an "unknown virus" as of January last year.

Many things were mysterious, such as "how do you get infected?", "What are the symptoms?", "Can you treat?", But many things have become clear in a year.

The virus is shed about two days before the onset, young people often have mild symptoms, and elderly people and people with chronic diseases are at high risk of becoming severe.

Among them, a measure to avoid the "three dense" of "sealed, dense, close" was proposed from an early stage by Japanese research.

The new coronavirus is characterized by the way the infection spreads.

Infected people do not evenly pass on to someone one after another, and when people gather in an environment where certain conditions are met, the risk of infection increases at that location.

That environment was "three dense".

In addition to the infection caused by flying, which was thought to be caused by influenza, it is thought that one of the causes is infection caused by the drifting of very small flying "micro flying".

This mode of spread is called a "super-spreading event."

The fact that the risk of infection increases when the environmental conditions are met, rather than being caused by a specific person, means that if the environment is not avoided, everyone may be transferred to many people.

On the contrary, if you thoroughly avoid "Three Cs", it may be possible to suppress the spread of infection.

Based on these "learned things", the government subcommittee points out that it is important to reduce the risk of infection at restaurants as a "key point" for infection control.

"Key points" of countermeasures Why restaurants?

One of the reasons why measures for eating and drinking places are emphasized is a paper published in the British scientific journal "Nature" last November by teams such as Stanford University in the United States.

In the paper, we will use mathematical model to determine where the spread of infection is likely to occur in major cities in the United States, using the location information data of about 98 million mobile phones from March to May last year. I did an analysis.

Among these, when we investigated what kind of stores would increase the infection when they resumed from closure, the one that was predicted to be most related to the spread of the infection was the "full-service restaurant."

This was followed by "sports gyms," "cafes," and "hotels."

Conversely, "gas stations," "pharmacy," "convenience stores," "new car dealers," etc. were predicted to be less relevant.

The treatise predicts that if a restaurant that was closed in Chicago, for example, reopens at "full service," about 600,000 new infections will occur in a month, which is the second most relevant. The number of people will be three times that of the reopening of a strong sports gym.

The research team says that the increased risk of infection in "full-service restaurants" is "probably due to the large number of visitors and the tendency to stay longer."

On the other hand, the treatise also includes analysis results that will give hints for reopening the restaurant.

It was predicted that if the number of people in various stores, including restaurants, was limited to 20% of the maximum capacity, the number of infected people could be reduced by 80%.

The team points out that "it is more effective to limit the capacity of the store than to limit the movement uniformly."

In addition to these treatises, the government's subcommittee identified measures centered on eating and drinking places as "the key points of infection control", referring to the results of analysis of clusters in Japan.

Of course, this is not just a "restaurant".

The risk of infection is thought to increase if there are places and opportunities for people to gather and eat and drink.

When eating, it is thought that the cause is that the mask is inevitably removed, conversations increase, and especially when drinking alcohol, the voice becomes loud and infection control becomes insufficient. I will.

Whether or not a state of emergency is declared, it is believed that the key to preventing the spread of infection is how much the risk of infection at eating and drinking places can be reduced.

Is it okay if I get the vaccine?

"Vaccination" is expected to be a trump card to prevent the spread of infection.

Vaccination has already begun overseas, such as in the United States and Europe, but preparations for vaccination are underway in Japan as well.

At a press conference by Prime Minister Suga on January 4, it was stated that "the government is working together to prepare for vaccination by the end of February."

We have summarized the expected effects and precautions of the vaccine.

Inoculation has already started overseas

By January 6th, a vaccine called "mRNA vaccine" developed by American pharmaceutical giant "Pfizer" and German biotechnology company "Biontech" has been submitted for approval in Japan.

According to the company, this vaccine is supposed to be given twice, and the inoculation is done by intramuscular injection instead of the subcutaneous injection used in influenza vaccines.

According to a paper summarizing the results of clinical trials conducted overseas, in clinical trials,

▼ Of the 20,000 people

who received the

vaccine, those who were infected with the new corona virus after the 7th day after the second vaccination While there were eight people,

▼ more than 20,000 people who were vaccinated with a fake vaccine called "Giyaku", 162 people were infected.

From this, it is said that the preventive effect of the vaccine is 95%.

In addition to Pfizer, vaccinations developed by pharmaceutical companies such as "Moderna" and "AstraZeneca" have begun overseas, and domestically produced vaccines are beginning to be used in Russia and China.

The Japanese government has signed contracts with three Western pharmaceutical companies, including Pfizer, to receive a total of 290 million supplies.

It's no longer safe when the inoculation starts ...

If vaccination starts in Japan, that is not the case.

Even if the vaccine works as expected, there are still challenges.

The first challenge is that it takes time to spread the vaccine to many people.

Vaccines are expected to be effective in preventing the spread of the virus by being inoculated by many people and having antibodies.

This new corona vaccine is to be given priority to high-risk people such as healthcare workers, the elderly, and people with underlying diseases in Japan, and it is necessary to spread it widely to the general public. It will take more time.

Widespread vaccination of many people can be a daunting task.

It is said that vaccination is not possible even though there is a vaccine unless you make thorough preparations in advance, such as what to do with the place to inoculate, in what order to inoculate, and how to inform the general public. It could be a situation.

The second issue is when the vaccine will be effective.

About 10 days after the first vaccination, the vaccine developed by Pfizer and others has become more susceptible to infection.

For this reason, the company says, "It suggests that a partial preventive effect can be obtained from an early stage."

However, the company says that it is necessary to receive a second vaccination to get the maximum preventive effect of this vaccine.

The second dose will be given 21 days after the first vaccination.

Even if vaccination starts, it does not seem to be effective immediately.

By the way, inoculating the vaccine twice is also done with a normal vaccine.

For example, in the case of influenza vaccine, children may not be able to get enough antibodies immediately after vaccination once.

However, when the second vaccination is given, the antibody rises quickly.

This is called "additional immunity" or "booster effect".

In addition, even with measles and rubella vaccines, some people lose their antibodies at a certain rate, so they are given twice.

Even if vaccination begins in Japan, it is necessary to stay alert and continue to take measures against infection, such as wearing masks and avoiding “three sickness”.

Another issue to consider is the problem of vaccine side reactions.

In the case of the vaccine developed by Pfizer and Biontech, no serious adverse reactions were reported in global clinical trials.

However, side reactions are inherent in vaccines, including minor ones.

Overseas, cases have been reported in which symptoms such as a strong allergic reaction called anaphylactic shock appeared after general vaccination began.

So far, the safety of the vaccine itself has not been questioned, but since vaccines are only given to healthy people, side reactions should be carefully monitored.

Professor Ken Ishii of the Institute of Medical Science, the University of Tokyo, who is familiar with vaccine development, said as follows.

Professor Ken Ishii

"We must avoid the fact that many people are flooded with vaccines and panic, and on the contrary, they are afraid of being unnecessarily scared and the tendency called" vaccine avoidance "spreads. It is necessary for society as a whole to take appropriate measures while considering the balance between the two, and no matter how effective the vaccine is, from the start of vaccination until the effect of suppressing the epidemic begins to appear and the effect can be felt further. I think we'll have to wait for four or five years. It will take some time before we can think,'You've stopped seeing corona infections lately.' "

Ima Mitani,

Reporter, Faculty of Science and Culture

Naoki Azuchi,

Reporter, Faculty of Science and Culture