Since its first appearance in the US five months ago, the H5N2 bird flu virus that has already caused the death toll of 21 million birds in the Midwest alone. Researchers acknowledge at the moment they still have limited knowledge about the bird flu virus that has endangered the turkey and egg-laying chicken population that supply most of the nation.
Federal agencies like the US Department of Agriculture, the Centers for Disease Control and Prevention are perplexed by the widespread range of the H5N2 virus, amid intensified biosecurity measures and apparent lack of expansive deaths in unprotected backyard flocks.
‘‘At this point, we don’t know very much about these viruses because they’ve only recently been identified, ‘‘We’re following the situation very closely because this is something we’re continuing to understand,” said Dr. Alicia Fry, CDC’s leader of the influenza prevention and control team.
Surfaced last winter in Canada, the current H5N2 virus was first recognized in the US early December, from a wild bird on the West Coast. Poultry operations in 8 Midwest states were found to be bird flu positive which forced producers to kill millions of turkeys and chickens.
Scientists speculated that maybe rats or small birds, seeking scrap food, brought the virus into the barns.
Or maybe flies were the courier, as the avian influenza virus were found on the insects in a 1983 Pennsylvania outbreak and in Japan last 2004. The USDA’s chief veterinarian even floated the idea last week wind may be blowing dust and feathers carrying the virus from the barnyard into buildings through air vents.
As operations were infected everyday, USDA epidemiologists tried to determine whether the virus came from a wild bird or may have spread to the poultry in a barn or a proximate farm.
Scientist finds it puzzling that there have been a swell in infections of backyard flocks. 12 cases were identified by USDA including 5 in Washington in January and February, and in Idaho, Kansas, Minnesota, Montana, Oregon, and Wisconsin.
Whether the virus will die as temperatures soar up and ultraviolet light surges, remains to be seen.
But director of the Southeast Poultry Research Laboratory in Athens, Ga., David Swayne, recognizes it’s hard to predict what the future holds.