Wild migratory birds may be more important carriers of avian influenza viruses from continent to continent than previously thought, according to new scientific research from the U.S. Geological Survey (USGS) that has important implications for highly pathogenic avian influenza virus surveillance in North America.
As part of a multi-pronged research effort to understand the role of migratory birds in the transfer of avian influenza viruses between Asia and North America, USGS scientists, in collaboration with the U.S. Fish & Wildlife Service in Alaska and the University of Tokyo, have found genetic evidence for the movement of Asian forms of avian influenza to Alaska by northern pintail ducks.
In an article published this week in Molecular Ecology, USGS scientists observed that nearly half of the low pathogenic avian influenza viruses found in wild northern pintail ducks in Alaska contained at least one (of eight) gene segments that were more closely related to Asian than to North American strains of avian influenza.
Researchers chose northern pintails as the focus of the study because they are fairly common in North America and Asia, they are frequently infected by low pathogenic avian influenza, and they are known to migrate between North America and Asia.
None of the samples were found to contain completely Asian-origin viruses and none were highly pathogenic.