How is H5N1 spreading in Asia?
The H5N1 virus is spread between birds through contact between an uninfected bird and an infected bird’s saliva, nasal secretions, or feces. The movement of infected poultry, contaminated poultry equipment, or people with virus-contaminated clothing or shoes results in the international movement of the H5N1 virus. Historically, the movement of poultry-adapted avian influenza strains does not involve wild birds. Recently, there has been some evidence that migratory waterfowl may have spread the Asian H5N1 “bird flu” virus to domestic poultry across national borders, but the mechanism of this spread is not yet fully understood and it is unknown if this virus will remain in wild bird populations once they are infected.