Armageddon: Scientists
have warned that a global viral outbreak is inevitable within five
years
THE symptoms appear suddenly with a headache, high
fever, joint pain, stomach pain and vomiting.
As the illness progresses, patients can develop large
areas of bruising and uncontrolled bleeding. In at least 30 per cent of cases,
Crimean-Congo Viral Hemorrhagic Fever is fatal.
And so it proved this month when a 38-year-old garage
owner from Glasgow, who had been to his brother’s wedding in Afghanistan, became
the UK’s first confirmed victim of the tick-borne viral illness when he died at
the high-security infectious disease unit at London’s Royal Free
Hospital.
It is a disease widespread in domestic and wild animals
in Africa and Asia — and one that has jumped the species barrier to infect
humans with deadly effect.
But the unnamed man’s death was not the only time
recently a foreign virus had struck in this country for the first
time.
Last month, a 49-year-old man entered London’s St
Thomas’ hospital with a raging fever, severe cough and desperate difficulty in
breathing.
He bore all the hallmarks of the deadly Sars virus that
killed nearly 1,000 people in 2003 — but blood tests quickly showed that this
terrifyingly virulent infection was not Sars. Nor was it any other virus yet
known to medical science.
Worse still, the gasping, sweating patient was
rapidly succumbing to kidney failure, a potentially lethal complication that had
never before been seen in such a case.
As medical staff quarantined their critically-ill
patient, fearful questions began to mount. The stricken man had recently come
from Qatar in the Middle East. What on earth had he picked up there? Had he
already infected others with it?
Using the latest high-tech gene-scanning technique,
scientists at the Health Protection Agency started to piece together clues from
tissue samples taken from the Qatari patient, who was now hooked up to a
life-support machine.
The results were extraordinary. Yes, the virus is from
the same family as Sars. But its make-up is completely new. It has come not from
humans, but from animals. Its closest known relatives have been found in Asiatic
bats.
The investigators also discovered that the virus has
already killed someone. Searches of global medical databases revealed the same
mysterious virus lurking in samples taken from a 60-year-old man who had died in
Saudi Arabia in July.
Potentially deadly: The
man suffered from CCHF, a disease transmitted by ticks (pictured) which is
especially common in East and West Africa
When the Health Protection Agency warned the world of
this newly- emerging virus last month, it ignited a stark fear among medical
experts.
Could this be the next bird flu, or even the next
‘Spanish flu’ — the world’s biggest pandemic, which claimed between 50 million
and 100 million lives across the globe from 1918 to 1919?
In all these outbreaks, the virus responsible came from
an animal. Analysts now believe that the Spanish flu pandemic originated from a
wild aquatic bird.
The terrifying fact is that viruses that manage to jump
to us from animals — called zoonoses — can wreak havoc because of their
astonishing ability to catch us on the hop and spread rapidly through the
population when we least expect it.
The virus's power and fatality rates are terrifying
One leading British virologist, Professor John Oxford
at Queen Mary Hospital, University of London, and a world authority on
epidemics, warns that we must expect an animal-originated pandemic to hit the
world within the next five years, with potentially cataclysmic effects on the
human race.
Such a contagion, he believes, will be a new strain of
super-flu, a highly infectious virus that may originate in some far-flung
backwater of Asia or Africa, and be contracted by one person from a wild animal
or domestic beast, such as a chicken or pig.
By the time the first victim has succumbed to this
unknown, unsuspected new illness, they will have spread it by coughs and sneezes
to family, friends, and all those gathered anxiously around them.
Thanks to our crowded, hyper-connected world, this
doomsday virus will already have begun crossing the globe by air, rail, road and
sea before even the best brains in medicine have begun to chisel at its genetic
secrets. Before it even has a name, it will have started to cut its lethal
swathe through the world’s population.
High
security: The high security unit where the man was treated for the potentially
fatal disease but later died
If this new virus follows the pattern of the pandemic
of 1918-1919, it will cruelly reap mass harvests of young and fit
people.
They die because of something called a ‘cytokine storm’
— a vast overreaction of their strong and efficient immune systems that is
prompted by the virus.
This uncontrolled response burns them with a fever and
wracks their bodies with nausea and massive fatigue. The hyper-activated immune
system actually kills the person, rather than killing the
super-virus.
Professor Oxford bases his prediction on historical
patterns.
The past century has certainly provided us with many
disturbing precedents. For example, the 2003 global outbreak of Sars, the severe
acute respiratory syndrome that killed nearly 1,000 people, was transmitted to
humans from Asian civet cats in China.
In November 2002, it first spread among people working
at a live animal market in the southern Guangdong province, where civets were
being sold.
Nowadays, the threat from such zoonoses is far greater
than ever, thanks to modern technology and human population growth. Mass
transport such as airliners can quickly fan outbreaks of newly- emerging
zoonoses into deadly global wildfires.
The Sars virus was spread when a Chinese professor of
respiratory medicine treating people with the syndrome fell ill when he
travelled to Hong Kong, carrying the virus with him.
By February 2003, it had covered the world by hitching
easy lifts with airline passengers. Between March and July 2003, some 8,400
probable cases of Sars had been reported in 32 countries.
It is a similar story with H1N1 swine flu, the 2009
influenza pandemic that infected hundreds of millions throughout the world. It
is now believed to have originated in herds of pigs in Mexico before infecting
humans who boarded flights to myriad destinations.
Once these stowaway viruses get off the plane, they
don’t have to learn a new language or new local customs.
Fears: Professor John
Oxford at Queen Mary Hospital warns of a pandemic within the next five
years
Genetically, we humans are not very diverse; an
epidemic that can kill people in one part of the world can kill them in any
other just as easily.
On top of this, our risk of catching such deadly
contagions from wild animals is growing massively, thanks to humankind’s
relentless encroachment into the world’s jungles and rainforests, where we
increasingly come into contact for the first time with unknown viral killers
that have been evolving and incubating in wild creatures for
millennia.
This month, an international research team announced it
had identified an entirely new African virus that killed two teenagers in the
Democratic Republic of the Congo in 2009.
The virus induced acute hemorrhagic fever, which causes
catastrophic widespread bleeding from the eyes, ears, nose and mouth, and can
kill in days.
A 15-year-old boy and a 13-year-old girl who attended
the same school both fell ill suddenly and succumbed rapidly. A week after the
girl’s death, a nurse who cared for her developed similar symptoms. He only
narrowly survived.
The new microbe is named Bas-Congo virus (BASV), after
the province where its three victims lived. It belongs to a family of viruses
known as rhabdoviruses, which includes rabies.
A report in the journal PLoS Pathogens says the virus
probably originated in local wildlife and was passed to humans through insect
bites or some other as-yet unidentified means.
There are plenty of other new viral candidates waiting
in the wings, guts, breath and blood of animals around us. You can, for example,
catch leprosy from armadillos, which carry the virus in their shells and are
responsible for a third of leprosy cases in the U.S.
Horses can transmit the Hendra virus, which can cause
lethal respiratory and neurological disease in people.
In a new book that should give us all pause for
thought, award-winning U.S. natural history writer David Quammen points to a
host of animal-derived infections that now claim lives with unprecedented
regularity. The trend can only get worse, he warns.
Quammen highlights the Ebola fever virus, which first
struck in Zaire in 1976. The virus’s power is terrifying, with fatality rates as
high as 90 per cent. The latest mass outbreak of the virus, in the Congo last
month, is reported to have killed 36 people out of 81 suspected
cases.
According to Quammen, Ebola probably originated in
bats. The bats then infected African apes, quite probably through the apes
coming into contact with bat droppings. The virus then infected local hunters
who had eaten the apes as bushmeat.
Quammen believes a similar pattern occurred with the
HIV virus, which probably originated in a single chimpanzee in
Cameroon.
'It is inevitable we will have a global outbreak'
Studies of the virus’s genes suggest it may have first
evolved as early as 1908. It was not until the Sixties that it appeared in
humans, in big African cities. By the Eighties, it was spreading by airlines to
America. Since then, Aids has killed around 30 million people and infected
another 33 million.
There is one mercy with Ebola and HIV. They cannot be
transmitted by coughs and sneezes. ‘Ebola is transmissible from human to human
through direct contact with bodily fluids. It can be stopped by preventing such
contact,’ Quammen explains.
‘If HIV could be transmitted by air, you and I might
already be dead. If the rabies virus — another zoonosis — could be transmitted
by air, it would be the most horrific pathogen on the planet.’
Viruses such as Ebola have another limitation, on top
of their method of transmission. They kill and incapacitate people too quickly.
In order to spread into pandemics, zoonoses need their human hosts to be both
infectious and alive for as long as possible, so that the virus can keep casting
its deadly tentacles across the world’s population.
But there is one zoonosis that can do all the right (or
wrong) things. It is our old adversary, flu. It is easily transmitted through
the air, via sneezes and coughs.
Sars can do this, too. But flu has a further advantage.
As Quammen points out: ‘With Sars, symptoms tend to appear in a person before,
rather than after, that person becomes highly infectious.
Isolation: Unlike Sars
the symptoms of this new disease may not be apparent before the spread of
infection
‘That allowed many Sars cases to be recognised,
hospitalised and placed in isolation before they hit their peak of infectivity.
But with influenza and many other diseases, the order is
reversed.’
Someone who has an infectious case of a new and
potentially lethal strain of flu can be walking about innocently spluttering it
over everyone around them for days before they become
incapacitated.
Such reasons lead Professor Oxford, a world authority
on epidemics, to warn that a new global pandemic of animal-derived flu is
inevitable. And, he says, the clock is ticking fast.
Professor Oxford’s warning is as stark as it is
certain: ‘I think it is inevitable that we will have another big global outbreak
of flu,’ he says. ‘We should plan for one emerging in 2017-2018.’
But are we adequately prepared to cope?
Professor Oxford warns that vigilant surveillance is
the only real answer that we have.
‘New flu strains are a day-to-day problem and we have
to be very careful to keep on top of them,’ he says.
‘We now have scientific processes enabling us to
quickly identify the genome of the virus behind a new illness, so that we know
what we are dealing with. The best we can do after that is to develop and
stockpile vaccines and antiviral drugs that can fight new strains that we see
emerging.’
But the Professor is worried our politicians are not
taking this certainty of mass death seriously enough.
Such laxity could come at a human cost so
unprecedentedly high that it would amount to criminal negligence. The race
against newly-emerging animal-derived diseases is one that we have to win every
time. A pandemic virus needs to win only once and it could be the end of
humankind.
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