Wild Birds - H5N1
Vectors Or Villains?

By Ed Stoddard
(Reuters) -- Do the wild birds that fly through cold winter skies to warmer lands silently carry deadly bird flu around the world, or, asks this story, are they simply potential victims?
The story says that many scientists believe migrating wild fowl are responsible for carrying the virus from Asia and Siberia to Romania and Turkey. And although some argue there is not enough evidence yet for firm conclusions, the theory is gaining ground.
The World Health Organization was quoted as saying in its latest bird flu fact sheet last week [3rd week December 2006] that, "Scientists are increasingly convinced that at least some migratory waterfowl are now carrying the H5N1 virus in its highly pathogenic form, sometimes over long distances, and introducing the virus to poultry flocks in areas that lie along their migratory routes," and that scientists found that viruses from the most recently affected countries, all of which lie along migratory routes, were almost identical to viruses recovered from dead migratory birds at Qinghai Lake in China. The viruses from Turkey's 1st human cases were also virtually identical to the Qinghai Lake strain, it added.
Juan Lubroth, the senior officer for infectious diseases with the United Nations Food and Agriculture Organization (FAO), was quoted as telling Reuters that, "We do know that avian influenza viruses are carried by migratory birds all over the world. But not all of them are highly pathogenic or H5N1. I think that wild birds may introduce the virus, but it is through man and man's marketing systems (the poultry trade) that the disease spreads. It is also possible that poultry can transmit the virus to wildlife when they share the same ecosystem."
The story goes on to say that the growing popularity of the migratory bird theory has worried an increasingly vocal group of conservationists who fear unfounded claims could lead to indiscriminate slaughters.
Dr. Richard Thomas of BirdLife International was quoted as telling Reuters that, "The pattern of outbreaks between Asia and eastern Europe do not follow any known pathway for migrant birds, which tend to fly on northerly-southerly routes. They don't go east-west."
Andre Farrar, an ornithologist with Britain's Royal Society for the Protection of Birds (RSPB), was cited as saying that if migratory birds were spreading H5N1, it would have been spotted elsewhere, adding, "Go back a stage and start off in southeast Asia. If migration was the primary route, you would have expected it in Australasia, but it hasn't shown up there. There is clearly a theoretical risk that migrant birds can carry bird flu. There is published work showing that ducks in captivity can survive H5N1 infection and can shed the virus, and we'd be foolish to ignore this."
Frosts Drive Birds To Turkey From Ukraine
(Reuters) -- Ukraine's agriculture ministry was cited as saying in a statement on Tuesday, 1-24-06, that severe frosts in Ukraine's southern Crimea peninsula have prompted migratory birds to leave the area for Turkey, lowering the risks of new domestic outbreaks of bird flu, adding, "A large number of migratory birds which traditionally winter in Crimea have left the region for Turkey. This could greatly improve the epizootic situation in southern Ukraine."
Ukrainian officials have detected bird flu in 23 Crimean districts so far. Testing showed the cases involved the deadly H5N1 strain of the disease.



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