MSNBC/Reuters 2/5/04: The 1918 flu virus, which killed 20 million people around the world, was probably so deadly because of a unique bird-like protein, U.S. and British scientists reported Thursday

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>

>Was 1918 epidemic related to bird flu?

>The 1918 flu virus, which killed 20 million people around the world,

>was probably so deadly because of a unique bird-like protein, U.S.

>and British scientists reported Thursday.

>http://www.msnbc.msn.com/id/4176602/

>

Was 1918 epidemic related to bird flu?

Virus behind deadly outbreak appears to be avian strain

 

Updated: 6:20 p.m. ET Feb. 05, 2004

 

WASHINGTON - The 1918 flu virus, which killed 20 million people

around the world, was probably so deadly because of a unique

bird-like protein, U.S. and British scientists reported Thursday.

 

Like a current outbreak of bird flu in east Asia, the 1918 influenza

appears to have jumped from birds to people with little change, they

wrote in this week's issue of the journal Science.

 

But unlike the 1918 flu, the current bird flu, which has killed 16

people, so far has not developed the mutation that allowed influenza

to decimate human populations 80 years ago.

 

" What (this study) says is this transmission between birds and humans

seems to be able to happen in more than one way, " John Skehel of

Britain's Medical Research Council, who led one study, said in a

telephone interview.

 

Clear hallmarks of a bird virus

Two teams of researchers analyzed samples of the virus from the 1918

outbreak and said it bears the clear hallmarks of a bird virus that

mutated very little before jumping from birds to people.

 

Health officials in China, Thailand, South Korea and Vietnam are

scrambling to control the current outbreak of avian influenza, known

as H5N1. It is lethal to people, which is often the case when viruses

leap from one species to another.

 

In 1997 when it first appeared in Hong Kong it was contained very

quickly because it did not spread from human to human, but only from

birds to people.

 

So far this year only 16 people have been killed, but there is some

evidence it may have begun spreading from person to person. If that

happens, experts fear the virus has the potential to be as bad as the

1918 epidemic.

 

Understanding just what it is about the viruses that makes them

deadly, and what makes them able to live and spread among humans,

will be key to controlling or pre-empting future epidemics, the

researchers noted.

 

Virus dug up from past

Skehel's team and another led by Ian Wilson at the Scripps Research

Institute in La Jolla, Calif., looked at bits of the virus extracted

from the bodies of victims, some buried in Alaska permafrost and

others saved in laboratory jars.

 

They looked specifically at a part of the virus called hemagglutinin,

which is a protein the virus uses to infect cells. Each strain of

virus has a unique hemagglutinin structure, and scientists believe

small mutations of the protein are what allows the virus to infect

new species.

 

The 1918 virus was an H1 virus -- different from H5N1.

 

They found it had some unique structures that may have given it

" novel mechanisms " for infecting people, Wilson and colleagues wrote.

This may explain why the 1918 epidemic killed so many young, healthy

adults.

 

And this explains why the current avian flu outbreak has, so far, not

lived up to fears, said Skehel.

 

" Presumably, what's blocking this current flu from spreading

person-to-person is that its hemagglutinin structure has not yet

evolved such that it can efficiently infect humans, " Skehel said in a

statement.

 

" This tells us more about the transmission of infections from birds

to humans, " he added.

 

" However, it will not have an immediate impact on the situation

currently unfolding in the Far East with the chicken flu known as H5,

since, from our previous work, we know that the 1918 and the H5

hemagglutinins are quite different. "

 

He said scientists should be testing birds for various forms of

influenza to see what else may be lurking out there with the

potential to infect people.

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