When I was 11 years old, I was scarred for life by the BBC. It was 1975 and the show was called Survivors. The title sequence begins 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 . . . and 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 spiralling back to the 14th century. For the Chinese scientist’s flask contained a bacterium even more deadly than Yersinia pestis, which is now generally recognised 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 travelled by rodent. Up to 60% of the population of Europe perished. Survivors imagined an even worse plague, originating, like the Black Death, in China. The BBC scriptwriters did their homework: the dying had all the symptoms of plague — swelling under the armpits, fever, vomiting of blood. Victims, as in the 14th century, died within a week of being infected. Rats had a starring role in the London scenes.
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 18th century and devastated China and India once again in the 1850s and 1890s. In 1918-19, the Spanish influenza pandemic killed between 20 million and 50 million people worldwide, roughly 1%-3% of the world’s population. Even in a normal year, respiratory diseases from influenza kill as many as 650,000 people globally.
So you won’t be surprised to hear that I have been obsessively tracking the progress of the Wuhan coronavirus ever since the Chinese authorities belatedly admitted that it can be passed from human to human.
The coronavirus is much scarier than ebola, which has produced outbreaks and epidemics in some African countries but has not produced an international pandemic because transmission via bodily fluid is difficult, its symptoms are too debilitating and it quickly kills most hosts. Viruses such as the one originating in Wuhan are highly infectious because they are airborne. This variant has the especially dangerous quality that symptoms do not manifest themselves until up to two weeks after an individual becomes infected — and contagious.
I have seen a few rash commentators downplaying the danger. But it is much too early to conclude, as Marc Siegel in the Los Angeles Times does, that the coronavirus “does not currently pose a threat [outside China] and may well never do so”. It is surely a mistake to worry, as did Farhad Manjoo in The New York Times, less about the virus than about “the amped-up, ill-considered way our frightened world might respond to it”. As for the complaint of CNN’s Brandon Tensley that the Trump administration’s coronavirus taskforce was insufficiently “diverse” — namely, it 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 is the virus’s reproduction number (R0) — the number of infections produced by each host — and its mortality rate, or the number of deaths per 100 cases. Early estimates by the World Health Organisation 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 in Maryland, by Saturday there were 12,024 confirmed cases and 259 deaths, for a mortality rate of 2.2%. But these numbers are likely to be underestimates.
In the initial outbreak, which began in late December, 27 of 41 infected individuals 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 2002-3.
One explanation is that the volume of air travel in China has ballooned since Sars. Its 100 busiest airports last year handled 1.2 billion passengers, up from 170 million. Wuhan’s Tianhe airport was almost as busy last year as Hong Kong’s was in 2002. Disastrously, the outbreak came not long before the Chinese lunar new year holiday — the peak travel season — and 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 24 countries other than China, including seven in America, four in Canada and two in the UK. 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 Nicholas 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 “standardised mortality units” (SMUs), where one SMU equals a mortality rate of 0.01% 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 about 20 times larger, for a death toll of 44.7 million.
“Standard individual-scale policy approaches such as isolation, contact tracing and monitoring are rapidly . . . overwhelmed in the face of mass infection,” Norman, Bar-Yam and Taleb conclude, “and thus . . . cannot be relied upon to stop a pandemic.” Decision-makers must act drastically and swiftly, avoiding “the fallacy that to have an appropriate respect for uncertainty in the face of possible irreversible catastrophe amounts to ‘paranoia’.”
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, Stanford