Australia has just experienced its first large scale deaths of wild seabirds from the highly pathogenic H5N1 bird flu (also known as avian influenza), indicating a major milestone in the nation’s fight against the worldwide bird flu pandemic. Anxieties are mounting among researchers, wildlife specialists and conservation agencies who are vigilant of the potential for the virus to become more widespread among indigenous avian fauna.
The H5N1 avian influenza strain has devastated wild and domestic bird populations throughout Asia Europe Africa and the Americas over the last few years, decimating millions of birds.
Australia, to date has escaped the severe effects on wildlife seen elsewhere. Now with the latest mass mortality event the virus appears to have reached a new stage in its worldwide spread: The first indications of the outbreak emerged from reports of large numbers of dead and dying seabirds along some sections of Australia’s coastline. Teams of veterinarians and wildlife experts were able to retrieve samples from some of the infected seabirds.
Testing in a laboratory established that it was the H5N1 virus which was causing the outbreak. Further testing is currently under way to establish exactly how widespread the infection is and which bird species are the most affected. Many seabird species live in high densities during their breeding season and when large colonies gather together at a breeding or migration site, it offers optimal circumstances for the transmission of infectious diseases.
Bird and wildlife health professionals are worried that migratory birds could play a role in the ongoing movement of the virus across countries and continents. Numerous species of seabird are known to undertake extensive migrations, tracking thousands of kilometers along different international flyways and routine disease surveillance is So an integral component of international avian influenza monitoring. Host countries, like Australia, collaborate with the international community in this research.
While the recent outbreak is focused on wild birds, authorities are enhancing surveillance around poultry farms. Commercial poultry farms have enhanced biosecurity in an effort to minimize contact between domestic poultry and infected wildlife. Containment of the outbreak within poultry remains a high priority as outbreaks will cause severe economic loss and threaten the food supply.
Health authorities stated that the threat to the general population is low. Infections in humans are extremely rare and have been mainly tied to prolonged contact with infected Poultry or contaminated environments and exposure. Yet, everyone has been urged to avoid contact with ill or dead birds and should report any unusual bird mortalities to the local wildlife or agricultural departments.
The focus of conservation groups is to particular species which are already under pressure from the environment. Certain populations of seabirds are affected by habitat destruction pollution change of climate and a reduction of food sources. An outbreak of infectious disease could cause more pressure on these fragile populations which conservation groups want to prevent.
Another key element that scientists are investigating is the pathogenicity of the virus. By studying different species of bird, they may discover that certain species have the ability to be susceptible to the virus but only develop mild symptoms, while other species develop high mortalities and more deadly symptoms. This information could help to fine-tune future surveillance programs and wildlife protection initiatives.
