Monday, October 24, 2005
Bird flu panic ignores and exaggerates risksBirdLife International have warned that hasty responses to Avian Influenza based on incomplete or unsound data could do great damage to birds and other biodiversity, while actually raising the risk to people and to the economically important poultry industry.
BirdLife International’s Partners throughout Europe, such as the RSPB (BirdLife in the UK ), are working or preparing to work with their governments to monitor migratory wild bird populations and to provide scientific data and expert guidance.
Recent outbreaks of the highly pathogenic H5N1 strain of avian influenza in Europe have occurred along migratory flyways (including the Danube delta, a great gathering place for migratory waterbird) during the autumn migration. There is no concrete evidence that migratory birds have helped transmit the disease between countries or regions, but the possibility cannot be ruled out.
The spread of H5N1 within and beyond South-east Asia appears attributable to movements of infected poultry. The patterns of spread are not consistent with the timing and direction of movements of wild birds. It is likely that H5N1 originated in domestic poultry through mutation of low pathogenic sub-types and was subsequently passed from poultry to wild birds.
Transmission is promoted in domestic flocks due to the density of birds and the consequent close contact with faecal and other secretions through which the virus can be transmitted. Husbandry methods in SE Asia where domestic flocks are often allowed to mix freely with wild birds, especially waterfowl will have facilitated the transmission to migratory waterbirds, leading to several reported instances of die-offs.
There is no evidence that H5N1 infection in humans have been acquired from wild birds. Human infections have occurred in people who have been closely associated with poultry. The risk to human health from wild birds is extremely low and can be minimised by avoiding contact with sick or dead birds. However, there is a possibility that this virus could develop into one that might be transmitted from human to human. If this happens, then it is most likely to happen in SE Asia, from where it could then spread rapidly around the world.
BirdLife International strongly opposes any suggestion that wild birds should be culled as a way of controlling the spread of the disease, on grounds of practicality and effectiveness, as well as conservation. Any such attempts could spread the virus more widely, as survivors disperse to new places, and healthy birds become stressed and more prone to infection. The World Health Organisation, Food and Agriculture Organisation and OIE (the World Organisation for Animal Health) agree that control of avian influenza in wild birds by culling is not feasible, and should not be attempted.
Similarly, attempts to drain wetlands, to keep waterbirds away are also likely to be counterproductive as well as disastrous for the environment, the conservation of threatened species, and for vital ecosystem services such as flood control and water cleansing. Birds will seek alternative staging places and waterbirds forced to fly further and endure more crowded conditions along their migration route will be more prone to infection. Some Asian and Middle Eastern governments are reported to be already formulating proposals for draining wetlands.
The most efficient control techniques involve improved biosecurity, to reduce contact between poultry and wild birds or infected water sources. Further measures include stricter controls or even bans on movements of domestic poultry, and on wild bird markets. Countries should also ban imports of wild-caught birds from infected areas. Such measures should be introduced worldwide.
BirdLife International therefore welcomes the recommendations by the European Commission that surveillance and biosecurity measures at poultry farms in the European Union should be strengthened, and that the Member States and experts have been advised to increase resources and efforts to monitor migratory bird species.
“We would like to offer our expertise in the Member States through our Partners and invite the EU state administrations to contact our Partners in country for help especially with the wild bird monitoring programmes,” said Dr Clairie Papazoglou, BirdLife International’s Head of EU Policy,.
BirdLife International’s Director of Science, Dr Leon Bennun, stressed the importance of informed and balanced judgement in responses to the threat of avian influenza, and in the public dissemination of information about it.
“It is important that discussions of the issues relating to avian influenza should differentiate between the real problems caused by the spread of the disease within bird populations, especially within the poultry industry, and the theoretical risks of a human pandemic.”
For additional information see the following update pages from:
Birdlife International e.g. There are 144 varieties of Avian Flu, most of which are benign to humans.
World Health Organisation
Food + Agriculture Organisation
Posted 9:37 pm by Matt Prescott