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Per capita, Japan has more elderly than every other country on the planet

Why have not more people in Japan died from Covid-19? It is just a macabre question that has spawned dozens of theories, from Japanese manners to claims that the Japanese have superior immunity.

Japan does not have the cheapest death rate for Covid-19 – in your community, South Korea, Taiwan, Hong Kong and Vietnam can all boast lower morbidity.

But in the early element of 2020, Japan saw fewer deaths than average. This is although in April, Tokyo saw about 1,000 “excess deaths’ – perhaps as a result of Covid. Yet, for the season as a whole, it will be possible that over all deaths will soon be down on 2019.

This is particularly striking because Japan has lots of the conditions which make it vulnerable to Covid-19, but it never adopted the energetic way of tackling the virus that some of its neighbours did.

What happened in Japan?

At the height of the outbreak in Wuhan in February, when the city’s hospitals were overwhelmed and the world set up walls to Chinese travellers, Japan kept borders open.

As the virus spread, it quickly became clear that Covid is an infection that primarily kills older people and is massively amplified by crowds or prolonged close contact. Per capita, Japan has more elderly than every other country. Japan’s population can be densely packed into huge cities.

Greater Tokyo includes a mind-boggling 37 million people and for some of them, the only path to get around is on the city’s notoriously packed trains.

Then there is Japan’s refusal to heed the advice of the World Health Organization (WHO) to “test, test, test”. Even now, total PCR tests stand at only 348,000, or 0.27% of Japan’s populace.

Nor has Japan had a lockdown on the scale or severity of Europe. In early April, the government ordered a state of emergency. But the stay-at-home request was voluntary. Non-essential businesses were asked to close, but there was no legal penalty for refusing.

Many paragons of Covid strategy, such as for instance New Zealand and Vietnam, used tough measures including closing borders, tight lockdowns, large-scale testing and strict quarantines – but Japan did none of that.

Yet, five months after the first Covid case was reported here, Japan has under 20,000 confirmed cases and under 1,000 deaths. The state of emergency has been lifted, and life is quickly returning to normal.

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Japan has already established a relatively low testing rate compared to places like South Korea

There is also growing scientific evidence that Japan really has contained the spread of the disease – so far.

Telecom giant Softbank carried out antibody testing on 40,000 employees, which showed that just 0.24% have been exposed to the virus. Randomised testing of 8,000 people in Tokyo and two other prefectures indicates even lower levels of exposure. In Tokyo just 0.1% returned positive.

As he announced the lifting of their state of emergency late last month, Prime Minister Shinzo Abe spoke proudly of the “Japan Model”, intimating that other countries should study from Japan.

Is there something special about Japan?

If you were to be controlled by Deputy Prime Minister Taro Aso, it’s down to the “superior quality” of Japanese people. In a now notorious comment, Mr Aso said he had been asked by leaders of other countries to explain Japan’s success.

“I told these people: ‘Between your country and our country, mindo (the level of people) is different.’ And that made them speechless and quiet.”

Literally translated, mindo means “people’s level”, although some have translated it as meaning “cultural level”.

It is a concept dating back to Japan’s imperial era and denotes a feeling of racial superiority and cultural chauvinism. Mr Aso has been roundly condemned for utilizing it.

But there is absolutely no doubt that numerous Japanese, plus some scientists, think there is something about Japan that’s different – a so called “Factor X” that is protecting the people from Covid-19.

It is possibly relevant that some aspects of Japanese mores – few hugs and kisses on greeting – have in-built social distancing, but nobody thinks that is the answer.

Does Japan have special immunity?

Tokyo University professor Tatsuhiko Kodama – who studies how Japanese patients react to the virus – believes Japan may have had Covid before. Not Covid-19, but something similar which could have left behind “historical immunity”.

This is how he explains it: When a virus enters our body, the disease fighting capability produces antibodies that attack the invading pathogen.

There are two types of antibody – IGM and IGG. How they respond can show whether someone has been subjected to the virus before, or something similar.

“In a primary (novel) viral infection the IGM response usually comes first,” that he tells me. “Then the IGG response appears later. But in secondary cases (previous exposure) the lymphocyte already has memory, and so only the IGG response increases rapidly.”

So, what happened with his patients?

“When we looked at the tests we were astonished… in all patients the IGG response came quickly, and the IGM response was later and weak. It looked like they had been previously exposed to a very similar virus.”

He thinks it will be possible a Sars-like virus has circulated in your community before, that might account for the low death rate, not merely in Japan, but in a lot of China, South Korea, Taiwan, Hong Kong and South East Asia.

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Activities like karaoke – which were branded high-risk – were popular in Japan

This has been met with some scepticism.

“I am not sure how such a virus could be restricted to Asia,” says Professor Kenji Shibuya, director of Public Health at Kings College, London and a former senior adviser to the federal government.

Professor Shibuya does not discount the possibility of regional differences in immunity or genetic susceptibility to Covid. But he is suspicious of the notion of a “Factor X” that explains the mortality differences.

He thinks countries that have done well in the combat Covid, did so for the same reason – they succeeded in dramatically reducing transmission.

Japanese people began wearing face masks significantly more than 100 years back during the 1919 flu pandemic and they have never really stopped. If you obtain a cough or a cold here it’s expected, you will don a mask to guard those around you.

“I think it (a mask) acts as a physical barrier. But it also serves as a reminder to everybody to be mindful. That we still have to be careful around each other,” says Keiji Fukuda, an influenza specialist and director of the School of Public Health at Hong Kong University.

Japan’s track and trace system also goes back to the 1950s when it battled a wave of tuberculosis. The government create a nationwide network of public health centres to spot new infections and report them to the health ministry.

If community transmission is suspected, a professional team is dispatched to track the infections, counting on meticulous human contact tracing and isolation.

Japan discovered the Three Cs early

Japan also discovered two significant patterns early in the pandemic.

Dr Kazuaki Jindai, a medical researcher at Kyoto university and person in the cluster-suppression taskforce, said data showed over a third of infections started in very similar places.

“Our figures… showed many infected people had visited music venues where there is screaming and singing… we knew that those were the places people needed to avoid.”

The team identified “heavy breathing in close proximity” including “singing at karaoke parlours, parties, cheering at clubs, conversations in bars and exercising in gyms” as the highest-risk activities.

Second, the team found that the infection’s spread was right down to a small percentage of these carrying the virus.

An early study found around 80% of these with SARS Covi-2 failed to infect the others – while 20% were highly infectious.

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The state of emergency failed to make staying home compulsory, but rather encouraged

These discoveries led to the federal government launching a nationwide campaign warning visitors to avoid the “Three Cs”.

  • Enclosed spaces with poor ventilation
  • Crowded places with many people
  • Close contact settings such as for instance face-to-face conversations.

“I think that probably worked better than just telling people to stay at home,” Dr Jindai says.

Although workplaces were left off the list, it was hoped the “Three Cs” campaign would slow spread enough in order to avoid lockdown – and fewer infections means fewer deaths.

For a little while it did – but in mid-March infections in Tokyo jumped and the town looked like it absolutely was on the path to exponential growth, like Milan, London and New York.

At this point Japan either got smart or got lucky. The jury is still on which.

Timing, timing

Professor Kenji Shibuya thinks the lessons from Japan are not so different from elsewhere: “To me, it was a timing lesson.”

Prime Minister Shinzo Abe ordered a – non-enforceable – state of emergency on 7 April, asking visitors to stay in the home “if possible”.

“If such measures were delayed, we might have observed a similar situation like New York or London. The death rate (in Japan) is low.

“But a current study by Columbia University suggests that if New York had implemented lockdown measure two weeks earlier in the day, it would have prevented thousands of deaths,” Prof Shibuya notes.

A recent report by the United States Centers for Disease Control and Prevention found people who have underlying medical ailments such as heart problems, obesity and diabetes are six times more likely to be hospitalised should they get Covid-19 and 12 times prone to die.

Japan has the lowest rates of coronary heart infection and obesity in the developed world. Still, boffins insist such vital signs do not explain everything.

“Those kinds of physical differences could have some effect but I believe the other areas are more crucial. We’ve learned from Covid that there is no simple explanation for any of the phenomena that we’re seeing. It’s a lot of facets contributing to the last outcome,” says Prof Fukuda.

The government asked, people listened

To return to Prime Minister Shinzo Abe’s boast of the “Japan Model” – is there a lesson to be learned?

Does the fact Japan has, so far, succeeded in keeping infections and deaths low, without shutting down or ordering people to stay at home, show a way forward? The answer is all depends.

There is not any “Factor X” – like every where else it has depended on the same thing – breaking the chain of transmission. In Japan, though, the federal government can depend on the public to comply.

Despite not ordering people to stay at home, generally, they did.

“It was lucky but in addition surprising,” Prof Shibuya says. “Japan’s mild lockdowns seems to have had a real lockdown effect. Japanese people complied despite the not enough draconian measures.”

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Much of Japan has now re-opened

“How do you reduce contact between infected and uninfected people…? You need a certain kind of response from the public, which I don’t think is going to be so easily replicated in other countries,” adds Prof Fukuda.

Japan asked people to be careful, stay away from crowded places, wear masks and wash their hands – and more often than not, that is precisely what most people did.

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