Monitoring the migration routes of wild birds could help to provide early warning of potential avian influenza outbreaks. This recommendation follows new research that found that migrating birds contribute to spreading deadly strains of avian flu around the world.
Some strains of avian flu viruses are highly lethal in the birds they infect and pose a major threat to poultry farms worldwide. In rare cases, the viruses can also infect people and cause life-threatening illness.
Researchers investigated how the H5N8 subtype of avian flu spread around the world following outbreaks in South Korea that began in early 2014. The virus spread to Japan, North America and Europe, causing outbreaks in birds there between the autumn of 2014 and the spring of 2015.
Scientists analyzed the migration patterns of wild birds that were found to be infected with the H5N8 virus. The team then compared the genetic code of viruses isolated from infected birds collected from 16 different countries.
Their findings revealed that H5N8 was most likely carried by the long-distance flights of infected migrating wild birds from Asia to Europe and North America via their breeding grounds in the Arctic.
Lead author Dr. Samantha Lycett of The University of Edinburgh's Roslin Institute said, “Bird flu is a major threat to the health and well-being of farmed chickens worldwide. Our findings show that with good surveillance, rapid data sharing and collaboration, we can track how infections spread across continents.”
The researchers said their findings reinforce the importance of maintaining strict exclusion areas around poultry farms to keep out wild birds.
Greater surveillance of wild birds at known breeding areas could help provide early warning of threats from specific flu virus strains to birds and people, they added.
Deadly avian flu strains — known as highly pathogenic avian influenza — can kill up to 100% of infected birds within a few days.
The study was conducted by the Global Consortium for H5N8 & Related Influenza Viruses and involved scientists from 32 institutions worldwide.
The study was published in the journal Science and was funded by the European Union’s Horizon 2020 research and innovation program COMPARE.