"U.S. Bird Experts Mystified By Midwest Avian Flu Spread"

"A virulent strain of avian flu that has killed turkeys in the heart of the nation's poultry region has been found through molecular testing to be nearly identical to viruses isolated in migratory ducks.

But some wildlife experts are skeptical of suggestions that wild birds are responsible for spreading the H5N2 flu strain that has infected poultry in Minnesota, Missouri and Arkansas.

A top investigator from the U.S. Department of Agriculture (USDA) says that testing performed by the government supports a conclusion that the virus is being carried by waterfowl along an established migratory route that stretches south from Minnesota to the Gulf of Mexico. The virus can be transmitted to poultry from ducks through droppings that land on farms or when birds interact, among other ways."

Tom Polansek reports for Reuters March 13, 2015.