Wetlands International argued earlier that a strong link of wild birds to the outbreaks in Africa was unlikely. Attention to the role of wild birds is needed, but the biggest threats for a global spread remain the transport of live birds- poultry and caged birds, as well as their products.
Recent work of Wetlands International and CIRAD in Africa in the framework of the FAO programme on avian influenza in wild birds has not found any evidence of HPAI H5N1 amongst 5000 samples of wild (water)birds.
Wetlands International has stated that wild birds, especially waterbirds, may very well carry the disease and transfer it to other birds, particularly in the water environment. A clear example are the European outbreaks among swans and in other birds in February of this year in Europe. The exact source of the introduction of the HP H5N1 in these cases remains unknown. A combination of multiple introductions from earlier infected areas in Russia and Ukraine, combined with unusual movements of birds in relation to exceptionally cold weather is one of the possible explanations. Spillback of virus from infected poultry to wild birds might play an important role. Unlike outbreaks in poultry, cases in wild birds often occur at small scale and rarely last long. They seem to be self-limiting.
The role of wild birds in transporting HP H5N1 over large distances remains unclear. Since the first outbreaks of HP H5N1 in Asia millions of waterbirds have flown back and forth in their migratory flyways, many passing infected areas. Large scale outbreaks in wild birds far away from earlier infected areas remain very rare. Outbreaks in poultry far from other areas with outbreaks can often with a higher likelihood be linked to other vectors (e.g import of chickens) than to wild birds. The case of Nigeria is a good example in this respect.
The extensive spread into Europe from Africa during - and - as a result of the spring migration of waterbirds, did not materialize, and this may be further evidence of the relatively minor role played by wild birds in the spread of this disease but really underscores how little is understood about the virus and its relation to wild birds. There is no guarantee that Europe will not be confronted with further and more severe outbreaks in the future.
Wetlands International, as a member of the Task Force Avian Influenza and Wild Birds, in cooperation with FAO, OIE, CIRAD, WCS and other major stakeholders in the fight against HP H5N1 continue to argue that better information is required about the virus and its spread amongst wild birds if we are to effectively minimize the risk of the virus. That is why Wetlands International is cooperating in initiatives like the AI programme of FAO and global initiative like GAINS (Global Avian Influenza Network for Surveillance) lead on by WCS.
While there is a need to stay alert on the situation in wild birds, far more attention needs to be given to monitoring and controlling the transport of poultry and other live birds and bird products
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Previous statements on the spread of Avian influenza by Wetlands International:
Also read our quotes in the New York Times article of May 10th 2006