October 31, 2005

Migratory birds might spread H5N1 bird flu to US

US scientists said migratory birds might carry the deadly H5N1 bird flu virus to northern American states next year, although waterfowl samples taken this year have tested negative for the disease.

The scientists from the University of Alaska, Fairbanks, had formed a bird flu programme to study the evolution and assess the prevalence of bird flu viruses in Alaska.

290 out of about 4,500 samples collected this summer were tested to detect the presence of any known strains of bird flu virus. The scientists said so far, none of the samples have tested positive for the deadly H5N1 strain, although 30 of the 290 samples showed the presence of other bird flu virus strains.

However, they expressed concern that H5N1 might reach US soil next year through migratory birds. They also called on the government to step up monitoring of migratory birds.

Alaska was at the overlap for parts of the Asian and North American migratory routes for wild birds, and could be the entry point of H5N1 into the US, the scientists said. In particular, birds might carry the H5N1 virus into Alaska next summer from Siberia, which was already hit by the disease.

The scientists also feared Alaska's environment was suitable for different bird flu virus strains to mix, and form a new deadly strain that would be capable of infecting humans.