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we live in an interconnected an
increasingly globalized world thanks the
international jet travel people and the
diseases they carry can be in any city
on the planet in a matter of hours
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and once the virus touches down
sometimes all it takes is one sneeze to
spread the infection throughout the
community when humans were
hunter-gatherers roaming the wild
savannas we were never in one place long
enough and settlements were not large
enough to sustain the transmission of
infectious microbes but with the advent
of the Agricultural Revolution 10,000
years ago and the arrival of permanent
settlements in the Middle East people
began living side by side with animals
facilitating the spread of bacteria and
viruses between cattle and humans
epidemics and pandemics come in many
shapes and forms in 2010 for instance a
devastating earthquake struck Haiti
forcing thousands of people into
temporary refugee camps within weeks the
camps are become breeding grounds for
cholera a bacteria sprayed by
contaminated water triggering a
countrywide epidemic but the most common
cause of epidemics are viruses such as
measles influenza and HIV and when they
go global
we call them pandemics pandemics have
occurred throughout human history some
have left scars on the tissue and bone
of their victims while evidence for
others comes from preserved DNA for
instance scientists have recovered DNA
from the bacteria that transmits
tuberculosis from the remains of ancient
Egyptian mummies
and in 2011 scientists investigating a
plague pit in the City of London were
able to reconstruct the genome of your
senior pestis the bacterium responsible
for the black death of the 14th century
it is thought the plague originated in
China in around 1314 spreading west
along the Silk Road the caravan route
running from Mongolia to the Crimea
in 1347 the plague reached the
Mediterranean and by 1400 it had killed
in excess of 34 million Europeans
earning it the title the great mortality
it was later historians who called it
the Black Death however by far the
greatest pandemic killer is influenza
flu is constantly circulating between
the Southern and Northern Hemisphere's
in North America and Europe seasonal
flus occur every autumn and winter as
the majority of children and adults
would have been exposed to the virus in
previous seasons these illnesses are
usually mild however every twenty to
forty years or so the virus undergoes a
dramatic mutation
usually this occurs when a wild flu
virus circulating in ducts and farm
poultry meets a pig virus and exchange
genes this process is known as antigenic
shift and has occurred throughout human
history the first recorded pandemic
occurred in 1580 the 18th and 19th
centuries saw at least six further
pandemics in terms of mortality none can
compare with the great flu pandemic of
1918
the first indication of the pandemic
came in the spring but American troops
in northern France began complaining of
chills headaches and fever then the
following September at a US army
barracks near Boston soldiers started
collapsing on parade prompting their
removal to the camp infirmary as a
surgeon there recalled two hours after
admission they have the mahogany spots
over the cheekbones and a few hours
later you can begin to see the cyanosis
extending from their ears and spreading
all over the face it is only a matter of
a few hours then until death comes and
it is simply a struggle for air until
they suffocate on the SS Leviathan a
huge American Transport enroute to
Bordeaux sick men hemorrhage blood from
their noses turning the decks between
their bunks
slick with bodily fluids meanwhile
British soldiers returning from northern
France on furlough introduced the flu to
Dover and other Channel ports from where
the virus was carried by rail to London
by the time the pandemic had run its
course in April 1919 an estimated 675
thousand Americans and 230,000 Britons
were dead in India alone some 10 million
were killed and worldwide the death toll
was an astonishing 50 million
but that was then today planes can
transport viruses to any country on the
globe in a fraction of the time it took
in 1918 in February 2003 for instance a
Chinese doctor arrived at the Metropole
Hotel in Hong Kong feeling unwell
unknown to him he was harboring a new
animal origin virus called SARS short
for severe acute respiratory syndrome
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within 24 hours of checking into room
nine one three sixteen other guests have
been infected and over the following
days five Porter planes to overseas
destinations spreading the virus to
Vietnam Singapore and Canada flights
between Hong Kong Toronto and other
international cities were quickly
grounded and thanks to other emergency
measures a pandemic was averted by the
time the outbreak was over four months
later SARS had infected 29 countries
worldwide and more than 1,000 people
were dead but all that the virus was
rapidly contained however there was
little that could be done about the
alarming news reports carried by cable
news channels and the internet as
bloggers added to the hysteria by
spreading unfounded conspiracy theories
tourism in Hong Kong and other affected
cities ground to a halt costing
businesses more than 10 billion u.s.
dollars one business however did very
well
above all SARS was a reminder that
pandemics have always been associated
with panic
if history teaches us anything it is
that while pandemics may start small
their impacts can be as dramatic as Wars
and natural disasters the difference
today is that science gives us the
ability to detect pandemics right at the
very beginning and to take action to
mitigate their impacts before they
spread too widely
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