Here is the article. I didn't re-read all of it yet, but guess they are saying it
hasen't spread from person to person
yet, but that they are afraid it eventually will.
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BL Fisher Note:
Apparently flu vaccines for chickens have the same problems that flu
vaccines
for humans have when it comes to getting the strains matched well....and
don't we all hope the millions of chicken eggs used to make human flu
vaccines
don't come from chickens in Asia.
www.newscientist.com/news/news.jsp?id=ns99994614Bird flu outbreak started a year ago
19:00 28 January 04
Exclusive from New Scientist Print Edition. Subscribe and get 4 free
issues.
In the past week, country after country has admitted that millions of
birds
and a few people have succumbed to bird flu, and it has become clear that
we
are facing the worst ever outbreak of the disease.
So how have things got so out of control? After strenuous denials,
Indonesia
has admitted the H5N1 virus has been spreading there since August.
Thailand
admits it had it in November. China says the disease was first detected
this
week.
In fact, the outbreak began as early as the first half of 2003, probably
in
China, health experts have told New Scientist. A combination of official
cover-up and questionable farming practices allowed it to turn into the
epidemic now under way.
Asia's growing prosperity has been accompanied by a boom in intensive
poultry production. After 1997, when all the chickens in Hong Kong were
destroyed after H5N1 bird flu killed six people, Chinese producers
decided
to take no chances, and started vaccinating birds with inactivated H5N1
virus.
This may have been a mistake. If the vaccine is not a good match for the
virus - as is the case with the H5N1 strain now sweeping Asia - it can
still
replicate but most animals do not show signs of disease. In this way, the
intensive vaccination schemes in south China may have allowed the virus
to
spread widely without being spotted.
"We don't like vaccination," says Hans Wagner of the UN Food and
Agriculture
Organization in Bangkok. This is also why the World Health Organization
has
reacted with dismay to Indonesia's announcement that it will tackle its
outbreak with vaccination instead of culling. Vaccination may even have
contributed to the origin of the latest variant of H5N1, as it would put
strains that could evade the vaccine at an advantage.
Single strain
The current strain resembles one first spotted late in 2002 in Penfold
Park,
Hong Kong. It appears to replicate more successfully than usual in ducks,
infects a wide range of wild birds and is shed orally as well as in
faeces -
all characteristics that help it spread.
The strains now causing the outbreaks in Korea and Vietnam are very
similar.
While samples from other countries are still being analysed, it looks as
if
all the outbreaks started with the large-scale distribution of one
strain,
says Klaus Stöhr, WHO head of influenza. "We are aware of samples taken
early last year that turned out to be this strain exactly." He will not
divulge their origin, but comments from other experts suggest it was
China.
The pattern of spread strongly suggests that the virus has been carried
by
people smuggling poultry, a practice reportedly widespread in south-east
Asia. Some experts blame migratory birds, but there is no evidence of
this.
It is certainly true that in regions with big outbreaks in poultry, local
wild birds are being affected. There are reports of mass die-offs of rare
birds in zoos in Thailand, and pigeons are said to be piling up in the
streets of Bangkok. However, regular monitoring of migratory birds in
Thailand has not revealed any signs of the virus.
Hopeful sign
For the WHO, the priority is now to prevent the epidemic triggering a
human
disaster. So far, fewer than a dozen human cases of bird flu have been
confirmed in Thailand, Vietnam and Cambodia, though there could well be
many
more unrecognised cases. "It is a hopeful sign that with all the heavy
exposure of people across such a large area, only a few are known to be
infected," Stöhr says.
So far at least, the virus seems incapable of human-to-human
transmission.
The great fear is that someone infected with both human flu and bird flu
will give rise to a lethal hybrid that can spread from person to person.
At a meeting in Geneva this week, the WHO asked pharmaceutical companies
and
governments for more antiviral drugs and ordinary flu vaccine to prevent
chicken handlers being infected by human flu at the same time as bird
flu.
But the scale is daunting. "We have 100,000 tablets of Tamiflu in
Vietnam,"
says Stöhr. "That's just a drop in the bucket." The story is similar with
the human flu vaccine.