The long
read
Why we need
worst-case thinking to prevent pandemics
Threats to
humanity, and how we address them, define our time. Why are we still so
complacent about facing up to existential risk? By Toby Ord
Fri 6 Mar
2020 06.00 GMT
The world
is in the early stages of what may be the most deadly pandemic of the past 100
years. In China, thousands of people have already died; large outbreaks have
begun in South Korea, Iran and Italy; and the rest of the world is bracing for
impact. We do not yet know whether the final toll will be measured in thousands
or hundreds of thousands. For all our advances in medicine, humanity remains
much more vulnerable to pandemics than we would like to believe.
To
understand our vulnerability, and to determine what steps must be taken to end
it, it is useful to ask about the very worst-case scenarios. Just how bad could
a pandemic be? In science fiction, we sometimes encounter the idea of a
pandemic so severe that it could cause the end of civilisation, or even of
humanity itself. Such a risk to humanity’s entire future is known as an
existential risk. We can say with certainty that the novel coronavirus, named
Covid-19, does not pose such a risk. But could the next pandemic? To find out,
and to put the current outbreak into greater context, let us turn to the past.
In 1347,
death came to Europe. It entered through the Crimean town of Caffa, brought by
the besieging Mongol army. Fleeing merchants unwittingly carried it back to
Italy. From there, it spread to France, Spain and England. Then up as far as
Norway and across the rest of Europe – all the way to Moscow. Within six years,
the Black Death had taken the continent.
Tens of millions
fell gravely ill, their bodies succumbing to the disease in different ways.
Some bore swollen buboes on their necks, armpits and thighs; some had their
flesh turn black from haemorrhaging beneath the skin; some coughed blood from
the necrotic inflammation of their throats and lungs. All forms involved fever,
exhaustion and an intolerable stench from the material that exuded from the
body.
There were
so many dead that mass graves needed to be dug and, even then, cemeteries ran
out of room for the bodies. The Black Death devastated Europe. In those six
years, between a quarter and half of all Europeans were killed. The Middle East
was ravaged, too, with the plague killing about one in three Egyptians and
Syrians. And it may have also laid waste to parts of central Asia, India and
China. Due to the scant records of the 14th century, we will never know the
true toll, but our best estimates are that somewhere between 5% and 14% of all
the world’s people were killed, in what may have been the greatest catastrophe
humanity has seen.
The Black
Death was not the only biological disaster to scar human history. It was not
even the only great bubonic plague. In AD541 the plague of Justinian struck the
Byzantine empire. Over three years, it took the lives of roughly 3% of the
world’s people.
When
Europeans reached the Americas in 1492, the two populations exposed each other
to completely novel diseases. Over thousands of years, each population had
built up resistance to their own set of diseases, but were extremely
susceptible to the others. The American peoples got by far the worse end of the
exchange, through diseases such as measles, influenza and, especially,
smallpox.
During the
next 100 years, a combination of invasion and disease took an immense toll –
one whose scale may never be known, due to great uncertainty about the size of
the pre-existing population. We can’t rule out the loss of more than 90% of the
population of the Americas during that century, though the number could also be
much lower. And it is very difficult to tease out how much of this should be
attributed to war and occupation, rather than disease. At a rough estimate, as
many as 10% of the world’s people may have been killed.
Centuries
later, the world had become so interconnected that a truly global pandemic was
possible. Towards the end of the first world war, a devastating strain of
influenza, known as the 1918 flu or Spanish flu, spread to six continents, and
even remote Pacific islands. About a third of the world’s population were
infected and between 3% and 6% were killed. This death toll outstripped that of
the first world war.
Yet even
events like these fall short of being a threat to humanity’s long-term
potential. In the great bubonic plagues we saw civilisation in the affected
areas falter, but recover. The regional 25%-50% death rate was not enough to
precipitate a continent-wide collapse. It changed the relative fortunes of
empires, and may have substantially altered the course of history, but if
anything, it gives us reason to believe that human civilisation is likely to
make it through future events with similar death rates, even if they were
global in scale.
The Spanish
flu pandemic was remarkable in having very little apparent effect on the
world’s development, despite its global reach. It looks as if it was lost in
the wake of the first world war, which, despite a smaller death toll, seems to
have had a much larger effect on the course of history.
The full
history of humanity covers at least 200,000 years. While we have scarce records
for most of these 2,000 centuries, there is a key lesson we can draw from the
sheer length of our past. The chance of human extinction from natural
catastrophes of any kind must have been very low for most of this time – or we
would not have made it so far. But could these risks have changed? Might the
past provide false comfort?
Our
population now is a thousand times greater than it was for most of human
history, so there are vastly more opportunities for new human diseases to
originate. And our farming practices have created vast numbers of animals
living in unhealthy conditions within close proximity to humans. This increases
the risk, as many major diseases originate in animals before crossing over to
humans. Examples include HIV (chimpanzees), Ebola (bats), Sars (probably civets
or bats) and influenza (usually pigs or birds). We do not yet know where
Covid-19 came from, though it is very similar to coronaviruses found in bats
and pangolins. Evidence suggests that diseases are crossing over into human
populations from animals at an increasing rate.
Modern
civilisation may also make it much easier for a pandemic to spread. The higher
density of people living together in cities increases the number of people each
of us may infect. Rapid long-distance transport greatly increases the distance
pathogens can spread, reducing the degrees of separation between any two
people. Moreover, we are no longer divided into isolated populations as we were
for most of the past 10,000 years.
Together
these effects suggest that we might expect more new pandemics, for them to
spread more quickly, and to reach a higher percentage of the world’s people.
But we have
also changed the world in ways that offer protection. We have a healthier
population; improved sanitation and hygiene; preventative and curative
medicine; and a scientific understanding of disease. Perhaps most importantly,
we have public health bodies to facilitate global communication and
coordination in the face of new outbreaks. We have seen the benefits of this
protection through the dramatic decline of endemic infectious disease over the
past century (though we can’t be sure pandemics will obey the same trend).
Finally, we have spread to a range of locations and environments unprecedented
for any mammalian species. This offers special protection from extinction
events, because it requires the pathogen to be able to flourish in a vast range
of environments and to reach exceptionally isolated populations such as
uncontacted tribes, Antarctic researchers and nuclear submarine crews.
It is hard
to know whether these combined effects have increased or decreased the
existential risk from pandemics. This uncertainty is ultimately bad news: we
were previously sitting on a powerful argument that the risk was tiny; now we
are not.
We have
seen the indirect ways that our actions aid and abet the origination and spread
of pandemics. But what about cases where we have a much more direct hand in the
process – where we deliberately use, improve or create the pathogens?
Our
understanding and control of pathogens is very recent. Just 200 years ago, we
didn’t even understand the basic cause of pandemics – a leading theory in the
west claimed that disease was produced by a kind of gas. In just two centuries,
we discovered it was caused by a diverse variety of microscopic agents and we
worked out how to grow them in the lab, to breed them for different traits, to
sequence their genomes, to implant new genes and to create entire functional
viruses from their written code.
This
progress is continuing at a rapid pace. The past 10 years have seen major
qualitative breakthroughs, such as the use of the gene editing tool Crispr to
efficiently insert new genetic sequences into a genome, and the use of gene
drives to efficiently replace populations of natural organisms in the wild with
genetically modified versions.
This
progress in biotechnology seems unlikely to fizzle out anytime soon: there are
no insurmountable challenges looming; no fundamental laws blocking further
developments. But it would be optimistic to assume that this uncharted new
terrain holds only familiar dangers.
To start
with, let’s set aside the risks from malicious intent, and consider only the
risks that can arise from well-intentioned research. Most scientific and
medical research poses a negligible risk of harms at the scale we are
considering. But there is a small fraction that uses live pathogens of kinds
that are known to threaten global harm. These include the agents that cause the
Spanish flu, smallpox, Sars and H5N1 or avian flu. And a small part of this
research involves making strains of these pathogens that pose even more danger
than the natural types, increasing their transmissibility, lethality or
resistance to vaccination or treatment.
In 2012, a
Dutch virologist, Ron Fouchier, published details of an experiment on the
recent H5N1 strain of bird flu. This strain was extremely deadly, killing an
estimated 60% of humans it infected – far beyond even the Spanish flu. Yet its
inability to pass from human to human had so far prevented a pandemic. Fouchier
wanted to find out whether (and how) H5N1 could naturally develop this ability.
He passed the disease through a series of 10 ferrets, which are commonly used
as a model for how influenza affects humans. By the time it passed to the final
ferret, his strain of H5N1 had become directly transmissible between mammals.
The work
caused fierce controversy. Much of this was focused on the information
contained in his work. The US National Science Advisory Board for Biosecurity
ruled that his paper had to be stripped of some of its technical details before
publication, to limit the ability of bad actors to cause a pandemic. And the
Dutch government claimed that the research broke EU law on exporting
information useful for bioweapons. But it is not the possibility of misuse that
concerns me here. Fouchier’s research provides a clear example of
well-intentioned scientists enhancing the destructive capabilities of pathogens
known to threaten global catastrophe.
Of course,
such experiments are done in secure labs, with stringent safety standards. It
is highly unlikely that in any particular case the enhanced pathogens would
escape into the wild. But just how unlikely? Unfortunately, we don’t have good
data, due to a lack of transparency about incident and escape rates. This
prevents society from making well-informed decisions balancing the risks and
benefits of this research, and it limits the ability of labs to learn from each
other’s incidents.
Security
for highly dangerous pathogens has been deeply flawed, and remains
insufficient. In 2001, Britain was struck by a devastating outbreak of
foot-and-mouth disease in livestock. Six million animals were killed in an
attempt to halt its spread, and the economic damages totalled £8bn. Then, in
2007, there was another outbreak, which was traced to a lab working on the
disease. Foot-and-mouth was considered a highest-category pathogen, and
required the highest level of biosecurity. Yet the virus escaped from a badly
maintained pipe, leaking into the groundwater at the facility. After an
investigation, the lab’s licence was renewed – only for another leak to occur
two weeks later.
In my view,
this track record of escapes shows that even the highest biosafety level
(BSL-4) is insufficient for working on pathogens that pose a risk of global
pandemics on the scale of the Spanish flu or worse. Thirteen years since the
last publicly acknowledged outbreak from a BSL-4 facility is not good enough.
It doesn’t matter whether this is from insufficient standards, inspections,
operations or penalties. What matters is the poor track record in the field,
made worse by a lack of transparency and accountability. With current BSL-4
labs, an escape of a pandemic pathogen is only a matter of time.
One of the
most exciting trends in biotechnology is its rapid democratisation – the speed
at which cutting-edge techniques can be adopted by students and amateurs. When
a new breakthrough is achieved, the pool of people with the talent, training,
resources and patience to reproduce it rapidly expands: from a handful of the
world’s top biologists, to people with PhDs in the field, to millions of people
with undergraduate-level biology.
The Human
Genome Project was the largest ever scientific collaboration in biology. It
took 13 years and $500m to produce the full DNA sequence of the human genome.
Just 15 years later, a genome can be sequenced for under $1,000, and within a
single hour. The reverse process has become much easier, too: online DNA
synthesis services allow anyone to upload a DNA sequence of their choice then
have it constructed and shipped to their address. While still expensive, the
price of synthesis has fallen by a factor of 1,000 in the past two decades, and
continues to drop. The first ever uses of Crispr and gene drives were the
biotechnology achievements of the decade. But within just two years, each of
these technologies were used successfully by bright students participating in
science competitions.
Such
democratisation promises to fuel a boom of entrepreneurial biotechnology. But
since biotechnology can be misused to lethal effect, democratisation also means
proliferation. As the pool of people with access to a technique grows, so does
the chance it contains someone with malign intent.
People with
the motivation to wreak global destruction are mercifully rare. But they exist.
Perhaps the best example is the Aum Shinrikyo cult in Japan, active between
1984 and 1995, which sought to bring about the destruction of humanity. It
attracted several thousand members, including people with advanced skills in
chemistry and biology. And it demonstrated that it was not mere misanthropic
ideation. It launched multiple lethal attacks using VX gas and sarin gas,
killing more than 20 people and injuring thousands. It attempted to weaponise
anthrax, but did not succeed. What happens when the circle of people able to
create a global pandemic becomes wide enough to include members of such a
group? Or members of a terrorist organisation or rogue state that could try to
build an omnicidal weapon for the purposes of extortion or deterrence?
The main
candidate for biological existential risk in the coming decades thus stems from
technology – particularly the risk of misuse by states or small groups. But
this is not a case in which the world is blissfully unaware of the risks.
Bertrand Russell wrote of the danger of extinction from biowarfare to Einstein
in 1955. And, in 1969, the possibility was raised by the American Nobel
laureate for medicine, Joshua Lederberg: “As a scientist I am profoundly
concerned about the continued involvement of the United States and other
nations in the development of biological warfare. This process puts the very
future of human life on earth in serious peril.”
In response
to such warnings, we have already begun national and international efforts to
protect humanity. There is action through public health and international
conventions, and self-regulation by biotechnology companies and the scientific
community. Are they adequate?
National
and international work in public health offers some protection from engineered
pandemics, and its existing infrastructure could be adapted to better address
them. Yet even for existing dangers this protection is uneven and
under-provided.
Despite its
importance, public health is underfunded worldwide, and poorer countries remain
vulnerable to being overwhelmed by outbreaks. Biotechnology companies are
working to limit the dark side of the democratisation of their field. For
example, unrestricted DNA synthesis would help bad actors overcome a major
hurdle in creating extremely deadly pathogens. It would allow them to get
access to the DNA of controlled pathogens such as smallpox (whose genome is
readily available online) and to create DNA with modifications to make the
pathogen more dangerous. Therefore, many synthesis companies make voluntary
efforts to manage this risk, screening their orders for dangerous sequences.
But the screening methods are imperfect, and they only cover about 80% of
orders. There is significant room for improving this process, and a strong case
for making screening mandatory.
We might
also look to the scientific community for careful management of biological
risks. Many of the dangerous advances usable by states and small groups have
come from open science. And we’ve seen that science produces substantial accident
risk. The scientific community has tried to regulate its dangerous research,
but with limited success. There are a variety of reasons why this is extremely
hard, including difficulty in knowing where to draw the line, lack of central
authorities to unify practice, a culture of openness and freedom to pursue
whatever is of interest, and the rapid pace of science outpacing that of
governance. It may be possible for the scientific community to overcome these
challenges and provide strong management of global risks, but it would require
a willingness to accept serious changes to its culture and governance – such as
treating the security around biotechnology more like that around nuclear power.
And the scientific community would need to find this willingness before
catastrophe strikes.
Threats to
humanity, and how we address them, define our time. The advent of nuclear
weapons posed a real risk of human extinction in the 20th century. There is
strong reason to believe the risk will be higher this century, and increasing
with each century that technological progress continues. Because these
anthropogenic risks outstrip all natural risks combined, they set the clock on
how long humanity has left to pull back from the brink.
I am not
claiming that extinction is the inevitable conclusion of scientific progress,
or even the most likely outcome. What I am claiming is that there has been a
robust trend towards increases in the power of humanity, which has reached a
point where we pose a serious risk to our own existence. How we react to this
risk is up to us. Nor am I arguing against technology. Technology has proved
itself immensely valuable in improving the human condition.
The problem
is not so much an excess of technology as a lack of wisdom. Carl Sagan put this
especially well: “Many of the dangers we face indeed arise from science and
technology – but, more fundamentally, because we have become powerful without
becoming commensurately wise. The world-altering powers that technology has
delivered into our hands now require a degree of consideration and foresight
that has never before been asked of us.”
Because we
cannot come back from extinction, we cannot wait until a threat strikes before
acting – we must be proactive. And because gaining wisdom takes time, we need
to start now.
I think
that we are likely to make it through this period. Not because the challenges
are small, but because we will rise to them. The very fact that these risks
stem from human action shows us that human action can address them. Defeatism
would be both unwarranted and counterproductive – a self-fulfilling prophecy.
Instead, we must address these challenges head-on with clear and rigorous
thinking, guided by a positive vision of the longterm future we are trying to
protect.
This is an
edited extract from The Precipice: Existential Risk and the Future of Humanity
by Toby Ord, published by Bloomsbury and available at guardianbookshop.com
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