All the birds in the Osceola County facility will be euthanized, according to a statement by the Iowa Department of Agriculture and Land Stewardship. The exact number of birds at the facility is unclear, department spokesman Dustin Vande Hoef said, "but it can house as many as 5.3 million."
State officials said they had quarantined the premises. The birds will be destroyed over the next week, Vande Hoef said.
"Birds from the flock will not enter the food system," according to a statement from the
The bird flu came to light when the mortality rate for the facility's chickens began to rise and the facility decided to run tests, Vande Hoef said. He did not identify the facility's operator.
The facility houses nearly 10% of the state's egg-laying chickens when at capacity, officials said.
There have been no reports of people being infected, according to the state's agriculture department. And officials said they believed the risk to people from the infections in wild birds, backyard flocks and commercial poultry "to be low."
It is the second outbreak of bird flu reported in Iowa this month.
Last week, avian influenza was discovered in a flock of 27,000 turkeys in Buena Vista County, the Des Moines Register reported. Those birds have been euthanized, it said.
On Friday, the bird flu was confirmed in a flock of 23,000 turkeys in Kandiyohi County, Minn., according to the USDA. In addition, 9,000 turkeys had exposure to that flock, the USDA said.
The virus was also confirmed in "33 mixed poultry" in Juneau County, Wis., on Friday, the USDA said.
On Monday, Hormel Foods Corp. said it expected to sell fewer turkeys this year because of bird flu outbreaks in multiple states, including Minnesota, where Hormel is based.
"We are experiencing significant challenges in our turkey supply chain due to the recent HPAI outbreaks in Minnesota and Wisconsin," Jeffrey M. Ettinger, the company's president and chief executive, said in a statement.
However, Hormel said it expected the bird flu outbreak occurrences to decline "as the weather improves."
Staff writer Lauren Raab contributed to this report.