AVIAN INFLUENZA: Information and On-going Research at the USGS Alaska Science Center
Quick Facts:
Numerous subtypes (16 HA and 9 NA) of type A avian flu occur naturally in birds. Most subtypes have no apparent affect on birds and do not spread to humans.
However, in 1997, one subtype – known as H5N1 or Highly Pathogenic Avian Influenza (HPAI) – led to the death of thousands of domesticated and wild birds in Asia. This virus can also infect humans, often with lethal consequences.
There are no verified cases of H5N1 human infection from wild birds, only from domestic fowl.
H5N1 has been detected in SE Asia, China, Africa, Russia, Eastern Europe, and Turkey as of March 2006.
Potential Movement of H5N1 to Alaska:
Many species that breed in Alaska migrate and winter throughout parts of Russia and Asia.
In Alaska, 620 waterbirds have been sampled for avian flu since July 2005. Among samples analyzed by the USGS National Wildlife Health Center, no H5N1 viruses have been detected.
Surveillance of wild birds for Avian Influenza will be continued during 2006 through sampling and research along trans-continental migratory pathways between Alaska and Asia for high priority species (see below).
Birds are captured using mist nets, nest traps, and corral traps. Samples for testing are collected from the cloaca following prescribed protocol (see Monitoring and Surveillance).
Wintering Spectacled Eiders in the Bering Sea between St. Lawrence and St. Matthew islands. Note fecal material accumulated on ice adjacent to the flocked birds.
Virus model showing hemagglutinin (HA) and neuraminidase (NA) surface proteins that vary among subtypes.
As of April 2006, the highly pathogenic strain of H5N1 avain influenza has not been observed in Alaska or elsewhere in North America.