No way to really contain this is there, if it's migratory wild birds? Is that your assumption now?
Experts debate possible bird flu spread to Europe
2/23/2004
BANGKOK - Could Asia's bird flu wing its way to Europe?
Millions of ducks, stints and storks will soon fly to north from their winter homes in Asia, fuelling fears they might carry the deadly H5N1 virus that has killed 22 people and ravaged poultry flocks across the region.
The World Health Organisation, which calls the Asian outbreaks "historically unprecedented", says wild birds could easily spread the disease.
It points to studies of past outbreaks that show infection can be introduced into domestic flocks by wild aquatic birds, including migratory birds capable of flying long distances.
"The virus multiplies in the intestines of these birds, which can carry the virus without developing signs of infection, and very large quantities of virus are shed in faeces," it said in a statement this week.
Part of the fear is that some wild birds can carry the virus but not necessarily fall ill from it, allowing them to spread it along migratory routes, their droppings contaminating water sources shared by domestic poultry.
"Once introduced into domestic flocks, the virus, which is highly contagious, can be mechanically carried from farm to farm via contaminated items such as vehicles, clothing and equipment".
But ornithologists, in a flap over the bad press swirling around wild birds, argue there is little proof wild fowl are guilty of spreading the species-jumping H5N1 virus afflicting eight Asian countries.
"These fears that birds will fly over cities, poop all over the place and spread the virus are becoming irrational," said Lew Young, manager of Hong Kong's Mai Po Nature Reserve.
"Wild birds can carry all kinds of viruses, but in this case the only dangerous one is H5N1 and the incidence is very low. It doesn't mean every single duck is heaving with H5N1," he said.
MIXING IT UP IN RUSSIA
The swift-moving virus has struck hardest in Thailand and Vietnam and continues to spread in China and even into mountainous Tibet.
In Thailand, authorities are testing 17 storks suspected of dying from the virus. Infections have also been reported in ducks, geese, turkeys, ostriches, quail, and peacocks.
Perhaps even more alarming, the virus has killed two domestic cats in Thailand, a veterinarian said on Friday. Earlier this week, it was confirmed H5N1 killed a rare clouded leopard at a zoo near Bangkok.
Bird experts argue the timing of the outbreaks and bird migration patterns in the region don't match up. But the speed of the disease has reinforced suspicions among those fighting the outbreaks that wild birds are responsible.
"We have several scenarios for the outbreaks and that is one possibility," said Hans Wagner, a senior Food and Agriculture Organisation (FAO) official in Bangkok. "If ducks have caught it and they have become a carrier, they can carry it back."
The FAO this week urged countries to be more vigilant against the threat posed by wild birds, but it opposed a mass cull which environmentalists fear some governments may consider.
Thailand is part of the East Asian-Australasian Flyway - one of the world's three major north-south routes for migratory fowl.
Millions of birds - ranging from shorebirds like the sandpiper and tiny curlew to larger cranes and storks - travel each year from Australia and Southeast Asia to breeding areas in northern China, the Russian Far East and even Alaska.
The Russian Far East may be the only place where infected Asian birds could pass on the virus to their European brethren migrating from Africa, experts say.
"Eastern Russia is an interesting theory," said Phil Hockey, a migration specialist with the Percy FitzPatrick Institute of African Ornithology in Cape Town.
"Infected birds would have to go long distances and if they are sick they won't be in enough nick to migrate," Hockey said.
Some bird experts argue there is evidence that the H5N1 virus is making wild birds sick, too.
Hockey said a bigger worry was the virus spreading through the lucrative, but illegal global trade in exotic birds.
Ornithologists say man's movement of domestic stock, and the capture or slaughter of wild birds brought into the farmyard, have also contributed to the spread of the virus.
"The issue is when somebody catches a wild-fowl, say, and keeps it penned up with his chickens and hens for a few days before taking it to market," said Colin Poole, a bird expert at the Wildlife Conservation Society in Cambodia.
"If they want to control this, countries such as China are going to have to start thinking about closing down wet markets, where live poultry and wild animals are kept close to each other for long periods of time."
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