+++ useless : expert +++++++++

Vaccines, Drugs No Answer to Birdflu, Experts say

USA : October 11, 2005


WASHINGTON - Many governments around the world are stockpiling
antiviral drugs and some companies are trying to speed up vaccine production
but these measure give a false sense of security and will do little to
counter a flu pandemic, an expert cautioned on Monday.


Michael Osterholm, an infectious disease expert who has been studying
the risk of pandemic flu for decades and is a US government adviser, said
governments should be preparing to cope with the pandemic instead of relying
entirely on the hope of using vaccines and drugs to control it.
If the H5N1 avian flu begins to easily infect humans, it will move too
quickly for drugs and vaccines to be of much use, Osterholm said.

"It doesn't matter if we have a vaccine now or not. We can't make it,"
Osterholm said in a telephone interview.

The H5N1 bird flu virus has killed at least 65 people in four Asian
nations since late 2003, and has killed or forced the destruction of tens of
millions of poultry.

Experts say it is mutating steadily and fear it will eventually
acquire the changes it needs to spread easily from person to person.

If it does, it will sweep around the world in months or even weeks and
could kill millions of people -- as many as 150 million, according to the
most dire forecast by the World Health Organization.

When avian flu infects people it looks like any other flu with
respiratory symptoms, fever and other common effects but it will kill many
more than the 500,000 people who die of ordinary flu each year around the
world.

People have known about the risk of an influenza pandemic for a very
long time, said Osterholm, an infectious disease specialist at the
University of Minnesota who advises the federal government on such issues.

"We have had a pandemic flu plan as a planning process since 1976,"
said Osterholm. "Nobody has completed it. It been one of the most
long-standing incompleted processes in Washington. Nobody wants to believe
that modern medical science can't handle something."

But it cannot, said Osterholm, who has seen the current US flu plan.
The plan has not been published yet but leaked versions suggest the country
has done little to prepare for an H5N1 pandemic.

Osterholm and other experts have long been complaining that there are
not sufficient hospital beds, equipment or trained workers to cope with a
major epidemic.

"The one thing I worry desperately about it is the impact of
overreliance on neuraminidase inhibitors," he said.

There are two drugs in the class -- Roche and Gilead's Tamiflu, known
generically as oseltamivir, and GlaxoSmithKline's Relenza.

They work to reduce the severity of annual influenza and may prevent
infection if used at the right time. Tests suggest they also work against
H5N1, but no one knows how well.

"I think that potentially neuraminidase inhibitors may work if you are
already on them as prophylaxis (prevention)," Osterholm said. That would
mean taking them daily for days or weeks.

"That means that very, very limited supply is going to become a lot
more limited."


FIGHTING OVER SCARCE SUPPLIES

The United States has enough courses of Tamiflu to treat about 2.3
million people. The Health and Human Services Department says another 2
million treatment courses are on order and will arrive by the end of the
year.

But some 90 million people would need the drug in the event of a flu
pandemic, University of Virginia flu expert Dr. Frederick Hayden told a
meeting on Saturday.

At current capacity, it would take about 10 years to produce enough
oseltamivir to treat 20 percent of the world's population, Hayden said.

"Now people are saying whoever has the most Tamiflu wins," Osterholm
said. "I worry so much that Tamiflu is a surrogate for protection."

And vaccines are not an answer yet and will not be for years. There is
an experimental vaccine against H5N1 but there are only a few thousand doses
of it.

It takes months to make influenza vaccine and H5N1 kills chickens --
the source of the eggs that are needed under current old-fashioned
production methods to make flu vaccines.

Companies are trying to develop more modern methods but are years away
from doing so. And work cannot begin on a true vaccine against H5N1 until it
actually starts infecting many people, because the vaccine must match the
virus precisely and no one can predict just how H5N1 will mutate.

And it is mutating.

A study published last week showed that the H1N1 virus that caused the
1918 flu pandemic, which killed at least 40 million people globally and may
have killed more, depending on estimates, was a purely avian virus that
acquired a few mutations that gave it the ability to infect people easily,
spread among them and cause highly fatal disease.

H5N1 is mutating in a similar way and experts believe it is only a
matter of time before it, too, infects people easily.



Story by Maggie Fox, Health and Science Correspondent


REUTERS NEWS SERVICE



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