Many people blame the coronavirus epidemic on globalization, and say that the only way to prevent more such outbreaks is to de-globalize the world. Build walls, restrict travel, reduce trade. However, while short-term quarantine is essential to stop epidemics, long-term isolationism will lead to economic collapse without offering any real protection against infectious diseases. Just the opposite. The real antidote to epidemic is not segregation, but rather cooperation.

Epidemics killed millions of people long before the current age of globalization. In the 14th century there were no airplanes and cruise ships, and yet the Black Death spread from East Asia to Western Europe in little more than a decade. It killed between 75 million and 200 million people – more than a quarter of the population of Eurasia. In England, four out of ten people died. The city of Florence lost 50,000 of its 100,000 inhabitants.

In March 1520, a single smallpox carrier – Francisco de Eguía – landed in Mexico. At the time, Central America had no trains, buses or even donkeys. Yet by December a smallpox epidemic devastated the whole of Central America, killing according to some estimates up to a third of its population.

In 1918 a particularly virulent strain of flu managed to spread within a few months to the remotest corners of the world. It infected half a billion people – more than a quarter of the human species. It is estimated that the flu killed 5% of the population of India. On the island of Tahiti 14% died. On Samoa 20%. Altogether the pandemic killed tens of millions of people – and perhaps as high as 100 million – in less than a year. More than the First World War killed in four years of brutal fighting.

In the century that passed since 1918, humankind became ever more vulnerable to epidemics, due to a combination of growing populations and better transport. A modern metropolis such as Tokyo or Mexico City offers pathogens far richer hunting grounds than medieval Florence, and the global transport network is today far faster than in 1918. A virus can make its way from Paris to Tokyo and Mexico City in less than 24 hours. We should therefore have expected to live in an infectious hell, with one deadly plague after another.

However, both the incidence and impact of epidemics have actually gone down dramatically. Despite horrendous outbreaks such as AIDS and Ebola, in the twenty-first century epidemics kill a far smaller proportion of humans than in any previous time since the Stone Age. This is because the best defense humans have against pathogens is not isolation – it is information. Humanity has been winning the war against epidemics because in the arms race between pathogens and doctors, pathogens rely on blind mutations while doctors rely on the scientific analysis of information.

An influenza camp, where patients were given "fresh air treatment," in 1918. Bettmann Archive/Getty Images

Winning the War on Pathogens

When the Black Death struck in the 14th century, people had no idea what causes it and what could be done about it. Until the modern era, humans usually blamed diseases on angry gods, malicious demons or bad air, and did not even suspect the existence of bacteria and viruses. People believed in angels and fairies, but they could not imagine that a single drop of water might contain an entire armada of deadly predators. Therefore when the Black Death or smallpox came to visit, the best thing the authorities could think of doing was organizing mass prayers to various gods and saints. It didn’t help. Indeed, when people gathered together for mass prayers, it often caused mass infections.

During the last century, scientists, doctors and nurses throughout the world pooled information and together managed to understand both the mechanism behind epidemics and the means of countering them. The theory of evolution explained why and how new diseases erupt and old diseases become more virulent. Genetics enabled scientists to spy on the pathogens’ own instruction manual. While medieval people never discovered what caused the Black Death, it took scientists just two weeks to identify the novel coronavirus, sequence its genome and develop a reliable test to identify infected people.

Once scientists understood what causes epidemics, it became much easier to fight them. Vaccinations, antibiotics, improved hygiene, and a much better medical infrastructure have allowed humanity to gain the upper hand over its invisible predators. In 1967, smallpox still infected 15 million people and killed 2 million of them. But in the following decade a global campaign of smallpox vaccination was so successful, that in 1979 the World Health Organization declared that humanity had won, and that smallpox had been completely eradicated. In 2019 not a single person was either infected or killed by smallpox.

A sparse international departures terminal at John F. Kennedy International Airport in New York City on March 7. Days later, as concerns over the coronavirus grew, President Trump announced restrictions on travelers from Europe. Spencer Platt—Getty Images

Guard Our Border

What does this history teach us for the current Coronavirus epidemic?

First, it implies that you cannot protect yourself by permanently closing your borders. Remember that epidemics spread rapidly even in the Middle Ages, long before the age of globalization. So even if you reduce your global connections to the level of England in 1348 – that still would not be enough. To really protect yourself through isolation, going medieval won’t do. You would have to go full Stone Age. Can you do that?

Secondly, history indicates that real protection comes from the sharing of reliable scientific information, and from global solidarity. When one country is struck by an epidemic, it should be willing to honestly share information about the outbreak without fear of economic catastrophe – while other countries should be able to trust that information, and should be willing to extend a helping hand rather than ostracize the victim. Today, China can teach countries all over the world many important lessons about coronavirus, but this demands a high level of international trust and cooperation.

International cooperation is needed also for effective quarantine measures. Quarantine and lock-down are essential for stopping the spread of epidemics. But when countries distrust one another and each country feels that it is on its own, governments hesitate to take such drastic measures. If you discover 100 coronavirus cases in your country, would you immediately lock down entire cities and regions? To a large extent, that depends on what you expect from other countries. Locking down your own cities could lead to economic collapse. If you think that other countries will then come to your help – you will be more likely to adopt this drastic measure. But if you think that other countries will abandon you, you would probably hesitate until it is too late.

Perhaps the most important thing people should realize about such epidemics, is that the spread of the epidemic in any country endangers the entire human species. This is because viruses evolve. Viruses like the corona originate in animals, such as bats. When they jump to humans, initially the viruses are ill-adapted to their human hosts. While replicating within humans, the viruses occasionally undergo mutations. Most mutations are harmless. But every now and then a mutation makes the virus more infectious or more resistant to the human immune system – and this mutant strain of the virus will then rapidly spread in the human population. Since a single person might host trillions of virus particles that undergo constant replication, every infected person gives the virus trillions of new opportunities to become more adapted to humans. Each human carrier is like a gambling machine that gives the virus trillions of lottery tickets – and the virus needs to draw just one winning ticket in order to thrive .

This is not mere speculation. Richard Preston’s Crisis in the Red Zone describes exactly such a chain of events in the 2014 Ebola outbreak. The outbreak began when some Ebola viruses jumped from a bat to a human. These viruses made people very sick, but they were still adapted to living inside bats more than to the human body. What turned Ebola from a relatively rare disease into a raging epidemic was a single mutation in a single gene in one Ebola virus that infected a single human, somewhere in the Makona area of West Africa. The mutation enabled the mutant Ebola strain – called the Makona strain – to link to the cholesterol transporters of human cells. Now, instead of cholesterol, the transporters were pulling Ebola into the cells. This new Makona strain was four times more infectious to humans.

As you read these lines, perhaps a similar mutation is taking place in a single gene in the coronavirus that infected some person in Tehran, Milan or Wuhan. If this is indeed happening, this is a direct threat not just to Iranians, Italians or Chinese, but to your life, too. People all over the world share a life-and-death interest not to give the coronavirus such an opportunity. And that means that we need to protect every person in every country.

In the 1970s humanity managed to defeat the smallpox virus because all people in all countries were vaccinated against smallpox. If even one country failed to vaccinate its population, it could have endangered the whole of humankind, because as long as the smallpox virus existed and evolved somewhere, it could always spread again everywhere.

In the fight against viruses, humanity needs to closely guard borders. But not the borders between countries. Rather, it needs to guard the border between the human world and the virus-sphere. Planet earth is teaming with countless viruses, and new viruses are constantly evolving due to genetic mutations. The borderline separating this virus-sphere from the human world passes inside the body of each and every human being. If a dangerous virus manages to penetrate this border anywhere on earth, it puts the whole human species in danger.

Over the last century, humanity has fortified this border like never before. Modern healthcare systems have been built to serve as a wall on that border, and nurses, doctors and scientists are the guards who patrol it and repel intruders. However, long sections of this border have been left woefully exposed. There are hundreds of millions of people around the world who lack even basic healthcare services. This endangers all of us. We are used to thinking about health in national terms, but providing better healthcare for Iranians and Chinese helps protect Israelis and Americans too from epidemics. This simple truth should be obvious to everyone, but unfortunately it escapes even some of the most important people in the world.

President Trump leaves the podium after announcing a national emergency during a news conference about the coronavirus at the White House in Washington, D.C., on March 13. Alex Brandon—AP

A Leaderless World

Today humanity faces an acute crisis not only due to the coronavirus, but also due to the lack of trust between humans. To defeat an epidemic, people need to trust scientific experts, citizens need to trust public authorities, and countries need to trust each other. Over the last few years, irresponsible politicians have deliberately undermined trust in science, in public authorities and in international cooperation. As a result, we are now facing this crisis bereft of global leaders that can inspire, organize and finance a coordinated global response.

During the 2014 Ebola epidemic, the U.S. served as that kind of leader. The U.S. fulfilled a similar role also during the 2008 financial crisis, when it rallied behind it enough countries to prevent global economic meltdown. But in recent years the U.S. has resigned its role as global leader. The current U.S. administration has cut support for international organizations like the World Health Organization, and has made it very clear to the world that the U.S. no longer has any real friends – it has only interests. When the coronavirus crisis erupted, the U.S. stayed on the sidelines, and has so far refrained from taking a leading role. Even if it eventually tries to assume leadership, trust in the current U.S. administration has been eroded to such an extent, that few countries would be willing to follow it. Would you follow a leader whose motto is “Me First”?

The void left by the U.S. has not been filled by anyone else. Just the opposite. Xenophobia, isolationism and distrust now characterize most of the international system. Without trust and global solidarity we will not be able to stop the coronavirus epidemic, and we are likely to see more such epidemics in future. But every crisis is also an opportunity. Hopefully the current epidemic will help humankind realize the acute danger posed by global disunity.

To take one prominent example, the epidemic could be a golden opportunity for the E.U. to regain the popular support it has lost in recent years. If the more fortunate members of the E.U. swiftly and generously send money, equipment and medical personnel to help their hardest-hit colleagues, this would prove the worth of the European ideal better than any number of speeches. If, on the other hand, each country is left to fend for itself, then the epidemic might sound the death-knell of the union.

In this moment of crisis, the crucial struggle takes place within humanity itself. If this epidemic results in greater disunity and mistrust among humans, it will be the virus’s greatest victory. When humans squabble – viruses double. In contrast, if the epidemic results in closer global cooperation, it will be a victory not only against the coronavirus, but against all future pathogens.

Copyright © Yuval Noah Harari 2020

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