Scientists say the millions of wild birds beginning their ancient, long-distance spring migrations may bring the virus with them into Alaska, where it would soon spread through the rest of the Americas, the Baltimore Sun reported.
"I think it is more likely than not that we are going to see (H5N1) bird flu in the Western Hemisphere," said Dr. William Schaffner, chairman of the department of preventative medicine at Vanderbilt University in Nashville, Tenn. "Whether it takes place during this migratory season or the next is uncertain."
Although human commerce and travel can explain some of the spread of the virus, its velocity in recent months has scientists increasingly convinced that wild birds, and perhaps bird migration, are also playing a significant role, the newspaper said.
"I think the evidence is now quite strong indicating that migratory birds are involved in serving as at least one carrier of the H5N1 subtype," said Dirk V. Derksen, supervisory wildlife biologist at the U.S. Geological Survey's Alaska Science Center in Anchorage.
2014: The Year in Music [PHOTOS]