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The deadliest virus we face is complacency

We don’t know enough yet to say how bad the coronavirus will be.

A passenger receives a temperature check before taking a flight bound for Wuhan at Haneda airport in Tokyo on Friday.Tomohiro Ohsumi/Getty

When I was 11, I was scarred for life by the BBC. It was 1975 and the show was called “Survivors.”

The title sequence began with a masked Chinese scientist dropping a glass flask. It smashes. We then see him boarding a plane to Moscow, where he starts to feel unwell. Suddenly, a naked arm falls lifeless across the screen. We see passport stamps for Berlin, Singapore, New York . . . finally London. And then a ghastly red stain spreads across the screen.

The genius of the series was that it was set in middle-class England — a serene Herefordshire of tennis courts, boarding schools, and stay-at-home wives. Within 10 minutes of episode one, however, that England was spiraling back to the 14th century. For the Chinese scientist’s flask contained a bacterium even more deadly than Yersinia pestis, which is now generally recognized to have caused the Black Death.

The Black Death — mainly bubonic plague but also the even more lethal pneumonic variant — killed between 75 million and 200 million people as it spread eastwards across Eurasia in the 1340s. The disease was transmitted by flea bites; the fleas traveled by rodent. Up to 60 percent of the population of Europe perished. Survivors imagined an even worse plague — originating, like the Black Death, in China.


I have long believed that, even with all the subsequent advances of medicine, we are far more vulnerable to a similar pandemic than to, say, climate change. Bubonic plague was a recurrent killer in Europe until the 17th century and devastated China and India once again in the 1850s. In 1918-19, as the First World War drew to a close, the Spanish influenza pandemic killed between 20 million and 50 million people worldwide, roughly 1-3 percent of the world’s population. Even in a normal year, respiratory diseases from influenza kill up to 650,000 people worldwide.


So you won’t be surprised to hear that I have been tracking obsessively the progress of the Wuhan coronavirus, ever since the Chinese authorities belatedly admitted that it can be passed from human to human.

I have seen a few rash commentators downplaying the danger. But it is much too early to conclude, with Marc Siegel in the Los Angeles Times, that the coronavirus “does not currently pose a threat [outside China] and may well never do so.” As for Brandon Tesley of CNN’s complaint that the Trump administration’s coronavirus task force was insufficiently “diverse” — i.e., has too many white men — heaven preserve us from woke public health policy.

We don’t know enough yet to say how bad this will be. Among the things we don’t know for sure are the virus’s reproductive rate (R0) — the number of infections produced by each host — and its mortality rate — the number of deaths per 100 cases. Early estimates by the World Health Organization suggest an R0 of between 1.4 and 2.5 — lower than the measles (12-18), but higher than SARS (0.5). According to Johns Hopkins University, by Friday evening there were 9,925 confirmed cases and 213 deaths, for a mortality rate of 2.1 percent. But these numbers are likely to be underestimates.

In the initial outbreak, which began in late December, 27 of 41 infected individuals had had direct exposure to the Wuhan food market where (incredibly, given the known risks) live bats were being sold for their meat. Since then, in the space of roughly a month, the disease has reached every province of the People’s Republic. This is far more rapid than the spread of SARS in 2002-03.


One explanation is that the volume of air travel in China has ballooned since SARS. China’s 100 busiest airports last year handled 1.2 billion passengers, up from 170 million back then. Wuhan’s Tianhe airport was almost as busy in 2019 as Hong Kong’s was in 2002. Disastrously, the outbreak came not long before the Chinese Lunar New Year holiday — the peak travel season. Disastrously, the regional and/or national authorities were slow to acknowledge how contagious the virus was.

At the time of writing, a total of 164 cases have been confirmed in 26 countries other than China, including five in the United States, two in Canada and two in Britain. In other words, we are now dealing with an epidemic in the world’s most populous country, which has a significant chance of becoming a global pandemic.

But how big a chance? How big a pandemic? And how lethal? The bad news, as Joseph Norman, Yaneer Bar-Yam, and Nassim Taleb argue in a new paper for the New England Complex Systems Institute, is that the answers lie in the realm of “asymmetric uncertainty” because pandemics have so-called fat-tailed (as opposed to normal or bell-curve) distributions, especially with global connectivity at an all-time high.


Researchers define the severity of pandemics using “standard mortality units” (SMUs), where one SMU equals a mortality rate of 0.01 percent or 770,000 deaths worldwide. A “moderate” global pandemic is defined as causing less than 10 SMU; a “severe” pandemic is above 10 SMU. Yet the average excess mortality of a moderate pandemic is 2.5 SMU, compared with 58 SMU for a severe pandemic. In other words, the mortality rate in a severe pandemic would be around 20 times larger, for a death toll of 44.7 million.

Thanks to the BBC, I have been paranoid about pandemics for more than 40 years. Nevertheless, the challenge is still to resist that strange fatalism that leads most of us not to cancel our travel plans and not to wear uncomfortable masks, even when a dangerous virus is spreading exponentially. Time to watch “Survivors” again. At home.

Niall Ferguson is the Milbank Family Senior Fellow at the Hoover Institution at Stanford University.