Title: BirdLife: Avian flu and wild birds (Dec 04 update)
Post by HKBWS Office on Dec 20th, 2004, 10:59pm
Source of information:
http://www.birdlife.net/action/science/species/avian_flu/index.html
Avian flu and wild birds
December 2004 update
BirdLife believes that it is very unlikely that wild birds are playing a significant part in the spread of Highly Pathogenic Avian Influenza (HPAI) because:- The outbreaks have not coincided with times of the year when birds undertake long-distance migrations. Scientists monitoring areas which overlap the south and east Asian flyways have found either no evidence of the avian flu virus, or different strains to that involved in the Asian outbreaks
- While it is common for wild birds, particularly waterbirds, to carry mild strains of avian influenza virus, there is little evidence that the new virulent H5N1 strain is affecting wild bird populations, or that wild birds are able to spread this Highly Pathogenic Avian Influenza virus
- A few individual wild birds have been found to be infected with the Highly Pathogenic form of the disease. This has generally been in circumstances which suggest that they have been in contact with infected poultry or poultry waste. When found, such birds have been either dead or dying, and in no condition to fly long distances. One reviewer of the literature says "no one has yet found Z-type H5N1 (the form causing outbreaks in Asia), to my knowledge, in a live wild bird healthy enough to migrate"
- There are no known cases of transmission between wild birds and humans
- The UN's Food and Agriculture Organisation (FAO) has stated that attempts to destroy wild birds or their habitat will not help to prevent or control avian influenza outbreaks. "Rather, authorities should take action to limit the exposure of farmed chickens and other poultry to wild birds by improving the biosecurity of farming enterprises"
Based on evidence from current and former outbreaks, BirdLife believes that intensive farming practices and inadequate disease reporting and control seem to be the main factors behind the spread of Highly Pathogenic Avian Influenza (HPAI). The solution lies in changing farming, trading and veterinary practices. This is where management measures should continue to be applied.
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