So far, so good. Although only a few of the results are in, the University of Alaska Program on the Biology and Epidemiology of Avian Influenza in Alaska reports that none of the samples taken from migratory waterfowl in the state this summer and screened to date have tested positive for the deadly H5N1 strain of bird flu virus being reported in Eurasia. Next summer the news may not be so good.
Alaska is at the overlap for parts of the Asian and North American flyways for migratory birds which scientists say could provide an opportunity for exchange of bird flu viruses which then could lead to the evolution of new strains of viruses that could infect humans.
Scientists at the University of Alaska Fairbanks formed the Avian Influenza Program to study the evolution and assess the prevalence of the many different avian influenza viruses in Alaska, including the highly disease-causing (pathogenic), H5N1 Asian subtype, in migratory birds. Researchers from UAF and collaborators from state, federal and private wildlife and public health agencies obtained cloacal samples from birds in the Minto Flats, Yukon Flats and Yukon Delta National Wildlife Refuges, Copper River Delta and other areas in the state this year.
Of the roughly 4,500 samples collected, 290 have been screened to determine the presence of any of the known subtypes of avian influenza virus. Thirty of the 290 samples tested positive for various bird flu viruses, but none of the viral isolation and subtyping to date has detected H5N1. The sample results will provide early detection for 2005 and baseline data for 2006 and subsequent years, which UAF researchers and others can use for compare to future samples and from which they hope to build predictive models of how the viruses mutate and move in the environment.
"With a virus like H5N1 emerging in an area like Southeast Asia and spreading toward Europe if it doesn't reach Alaska this year, those birds that go back may very well pick it up and bring it to Alaska next year to an environment where that H5N1 might mix with other strains it hasn't seen before," said Jonathan Runstadler, a lead scientist on the project, assistant professor of biology and wildlife at UAF's Institute of Arctic Biology and a veterinarian.
"I think we did a good job for this year in what we set out to do -- getting samples from various parts of the state and from a variety of different species, but there are areas of the state we didn't cover, particular sites and species we could use samples from," Runstadler said.