Iowa Farm's 5.3M Hens Will Be Killed Biggest outbreak in current bird flu epidemic affects 10% of Iowa's egg-laying hens By Evann Gastaldo, Newser Staff Posted Apr 21, 2015 6:52 AM CDT Updated Apr 21, 2015 7:42 AM CDT 34 comments Comments This Sept. 10, 2008, file photo shows chickens huddling in their cages at an egg processing plant at the Dwight Bell Farm in Atwater, Calif. (AP Photo/Marcio Jose Sanchez File) (Newser) – The last thing you want at a farm with 5.3 million chickens: avian flu. But the Agriculture Department confirms that's what has hit an egg producer in Osceola County, Iowa; it's the biggest outbreak so far in the current H5N2 bird flu epidemic. CNN reports that all of the hens will be euthanized; officials previously told the New York Times they didn't yet know how many of the 25 barns at the farm were affected, though birds in three barns had already been killed in an effort to halt the spread. "When there's an outbreak like this, you have to make sure the disease doesn't leave," the state's ag secretary tells the Des Moines Register. Iowa is the biggest egg producer in the country, and the farm in question accounts for almost 10% of Iowa's egg-laying hens. The outbreak has hit chicken and turkey producers in 13 states, many in the Midwest—Gov. Scott Walker declared a state of emergency in Wisconsin yesterday and authorized the National Guard to get involved—and has killed almost 7.8 million birds since last month. The risk of transmission to people is considered to be low, and the egg market will likely only see a limited effect.