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©
Macmillan Publishers Ltd 2005
Taken from the
Magazine
section in
www.onestopenglish.com
Back from the dead
By Ian Sample
Many people today are worried about bird
flu. They are afraid that it will pass from
birds to humans
and that thousands of
people will die in a pandemic. In 1918 a flu
virus killed about 50 million people around
the world. The virus was called Spanish
influenza (or Spanish flu, for short) because
Spanish newspapers first described the
disease. Now, after nine years of work,
scientists in an American laboratory in
Atlanta, Georgia,
have produced a copy of
the Spanish flu virus. They are also going to
publish the genetic sequence of the virus on
the internet and some experts are afraid that
other laboratories could copy the virus.
Scientists have copied the virus because they
want to understand why the 1918 Spanish
flu pandemic killed so many people. In a
report in the journal Science, Dr Jeffery
Taubenberger and
a team of scientists in the
USA show that the copied virus is extremely
powerful. The scientists injected the virus
into mice and the mice began to lose weight
very quickly. They lost 13% of their weight
in two days and all of the mice died within
six days.
"I didn't expect it to be as lethal as it was,"
Dr Terrence Tumpey,
one of the scientists in
the team, told the journal Nature. In another
experiment, they injected more mice with a
normal type of flu. The mice lost weight at
first but then they got better and did not die.
The experiments showed that the mice with
the Spanish flu virus had 39,000 times more
flu virus in their bodies than the second
group of mice.
The scientists who copied the virus say their
work has already provided important
information about
the virus and helps to
explain why it is so lethal. But other experts
are worried that the virus could escape from
the laboratory. "Some people will think that
they have really created a biological weapon,"
said Professor Ronald Atlas of the University
of Louisville in Kentucky. "I am even more
worried now than I was before about the
possibility of a flu pandemic. The 1918 flu
pandemic started with
bird flu and that might
happen again today with Asian bird flu."
Some scientists are worried about the
publication of the genetic sequence on the
internet. They are afraid that biologists could
copy the virus using the information on the
internet. This could be very dangerous.
It took a long time to copy the virus. Scientists
used material taken from the lungs of people
who died from the flu virus in 1918. In a
second report in Nature, Taubenberger and his
colleagues analyzed
the genetic make-up of
the virus. They were surprised to find that it
was completely different from all the normal
human flu viruses. This probably means that
Spanish flu jumped from birds to humans and
did not mix with a human virus first. This is
very worrying for scientists because in the past
everyone believed that a pandemic was only
possible if a bird flu
virus mixed with a human
flu virus.
Taubenberger says it is very important to
know what changes in the virus caused the
1918 Spanish flu virus. This will help
scientists to work out which viruses might
cause a pandemic. The H5N1 bird flu in Asia
is already changing and it could infect
humans, he said.
Viruses have escaped from high-security labs
before. The Sars
virus escaped at least twice,
once in Taiwan and once in Singapore. But
some scientists believe a pandemic will not
happen even if the virus escapes, because most
people are naturally immune and there are
now a lot of drugs which protect people
from flu.
The Guardian Weekly XXX, page X