WASHINGTON, May, 1, 2015 – Iowa officials have identified five probable cases of highly pathogenic bird flu in the state, one involving a commercial egg-laying operation Buena Vista County housing an estimated 5.5 million birds.

If confirmed, the number of chickens and turkeys affected by the disease nationwide in the current outbreak will surpass 20 million, which may be the most in U.S. history. In Iowa alone, the number of affected chickens in egg-laying operations would be around 15 million, or about a quarter of the egg-laying hens in the nation’s biggest egg producing state. State officials had previously announced 12 outbreaks.

As per national policy, all of the birds on premises where the H5N2 virus is confirmed are being humanely destroyed to slow the spread of the disease. The farms are also being quarantined.

Three new presumptive cases were also reported yesterday in commercial turkey flocks in Minnesota, the biggest turkey producing state. Flocks totaling about 4 million birds have already been euthanized in the state.

A spokeswoman for USDA’s Animal and Plant Health Inspection Service said there was an outbreak of high path bird flu in the 1980s affecting about 17 million birds. She said APHIS is also trying to confirm numbers from a major outbreak in 1924.

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