Thaindian News

Washington, March 25 (IANS) Wild migratory birds may indeed play a role in the spread of bird flu, also known as highly pathogenic avian influenza H5N1.

The H5N1 virus continues to re-emerge across much of Eurasia and Africa, with high fatality rates in people, and the threat of a possible global pandemic.

A study by the US Geological Survey (USGS), the United Nations Food and Agriculture Organization and the Chinese Academy of Sciences used satellites, outbreak data and genetics to uncover an unknown link in Tibet among wild birds, poultry and the movement of often-deadly virus.

Researchers attached GPS satellite transmitters to a group of bar-headed geese - a wild specie that migrates across most of Asia and that died in the thousands in the 2005 bird flu outbreak in Qinghai Lake, China, according to a USGS statement.

GPS data showed that wild geese tagged at Qinghai Lake spend their winters in a region outside of Lhasa, the capital of Tibet, near farms where H5N1 outbreaks have occurred in domestic geese and chickens.

This is the first evidence of a mechanism for transmission between domestic farms and wild birds, said Diann Prosser, a USGS biologist at its Patuxent Wildlife Research Center.

“Our research suggests initial outbreaks in poultry in winter, followed by outbreaks in wild birds in spring and in the breeding season.

“The telemetry data also show that during winter, wild geese use agricultural fields and wetlands near captive bar-headed geese and chicken farms where outbreaks have occurred.”

The part that wild birds play in the spread of bird flu has been hotly debated since the 2005 outbreaks in Qinghai Lake.

Bird flu that spread beyond Asia and into Europe and Africa was later found to have genetically originated in the Qinghai Lake area. Discovering the Tibet connection adds another significant link in the global transmission of bird flu.

The study also uncovered an undocumented migratory link between Qinghai Lake and Mongolia, further suggesting that Qinghai may be a pivotal point of H5N1 transmission.

Scott Newman, Head of the Wildlife Health and Ecology Unit of the FAO, noted that “H5N1 outbreaks along this flyway mirror human and poultry densities, with domestic poultry the primary reservoir for this disease”.