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European Union for Bird Ringing The highly pathogenic strain of H5N1 Avian Influenza (AI) is now present in wild birds in Europe. Cases have also been reported from domestic poultry. The European Union for Bird Ringing (EURING) is concerned to ensure that critical data gathering on the movements and population dynamics of wild bird populations is maintained, while taking all reasonable precautions to minimize the chances of H5N1 being transmitted to those who need to handle wild birds for field research. The risk of H5N1 being transmitted to humans from wild birds is extremely low, and can be further reduced by good hygiene. It is also essential that ringers should follow hygiene procedures and movement patterns that minimize the risk of transmitting Avian Influenza from wild birds to domestic poultry. Ringers already follow appropriate hygiene procedures, following advice from their national Ringing Schemes. EURING is working to ensure that the most up-to-date information on best practice is available to all European Ringing Schemes and will keep this advice updated as necessary. Avian influenza There are at least 144 strains of avian influenza, most of which have low pathogenicity (LPAI). They circulate in wild birds at low levels, though they tend to be more common in waterbirds, particularly wildfowl. A highly pathogenic strain, H5N1, is currently causing concern. It emerged in Southeast Asia in the late 1990s, spread to the west and has recently been found in Western Europe. HPAI viruses are of concern as they cause high mortality in domestic poultry flocks. Transmission to humans is extremely rare, but when it occurs the disease is often fatal. A major concern is that the recombination of H5N1 with a human influenza virus could produce a highly pathogenic form that was readily transmissible between humans. Such a form could give rise to a global pandemic. H5N1 is rare in wild birds. This and other forms of AI may be passed on via bird faeces and in other secretions. Transmission of H5N1 to humans has occurred where people live in close proximity to infected domestic poultry. There are no proven cases of transmission from wild birds to humans, so even if the highly pathogenic form of H5N1 avian influenza is present, the risk of transfer to bird ringers is thought to be extremely low. Why continued bird ringing is essential Bird ringing (including conventional metal ringing, colour marking, radio and satellite tracking) is the primary source of information on bird movements. A proper understanding of migration routes and how they are changing can only be achieved by following the movements of individually marked birds. We need such information to understand the role that wild birds may play in the spread of Avian Influenza itself, as well as for many other applied problems. Such information is important for governments and the poultry industry when considering how HPAI may be spread by the movements of wild birds. EURING and Wetlands International have been collaborating to provide the European Commission with an up-to-date assessment of bird movements in relation to Avian Influenza. EURING’s member Ringing Schemes are frequently key advisors to their national governments in relation to bird movements and Avian Influenza. A number of analyses of ringing data that will help to improve the scientific basis of such advice are currently in progress. Much information on bird movements is held in the EURING databank (http://www.euring.org/edb) and is published in national migration atlases and research papers. However, migration patterns can change rapidly in relation both to short-term events such as severe weather and to long-term factors such as global climate change. Continued data gathering is therefore essential. Many live and dead birds are now being examined by veterinary centres as part of AI surveillance programmes. Where such birds carry rings it is essential that they should be reported to the relevant national ringing centres to provide links between the AI status and movements of individuals. Continued bird ringing is also essential for much other applied work on bird populations. Specially designed ringing programmes such as “Constant Effort Sites” provide key demographic monitoring data on bird populations that help to identify population declines and their likely solutions. Studies of marked birds are essential wherever estimates of demographic parameters such as survival or dispersal are required. This includes research into the mechanisms of population declines in species of conservation concern and conversely investigations of the causes of increase of pest species. Bird ringing is also an essential mechanism for studying the moult and condition of birds, allowing studies of annual cycles and of the importance of particular areas for pre-migratory fattening. Many of these processes are changing rapidly as a result of global climate change and other environmental factors. Such research is therefore of urgent applied importance. EURING considers that it is important that the types of studies outlined above should be maintained. We believe that this can be done in the presence of H5N1 within wild bird populations, provided that appropriate hygiene procedures are followed by bird ringers. Hygiene best practice when catching and handling birds for ringing Birds may carry a variety of diseases including Avian Influenza, and ringers should therefore always practice good hygiene when handling birds. The aims of hygiene procedures should be to prevent disease transmission from birds to ringers, from wild to domestic birds and also to prevent disease transmission between birds during the catching and handling process. Strict care must also be taken to eliminate any risk of transferring contaminated material (e.g. bird faeces) into areas containing domestic poultry. The stringency of the hygiene procedures to be followed may need to be adapted in relation to the probability that the species being handled could carry H5N1, the prevalence of H5N1 within the country, region or flyway concerned and local field conditions. National Ringing Schemes are responsible for issuing and enforcing guidelines on hygiene to their ringers. EURING will promote best practice by disseminating relevant information to all Ringing Schemes via its website. Further details of the specific procedures that should be followed by ringers are available via the EURING website and will be updated as new information becomes available. European Union for Bird Ringing |
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