INDIANAPOLIS (AP) -- Animal health officials investigating a bird flu strain that affected 10 turkey farms in southwestern Indiana have added 156,000 chickens to the list of thousands of birds being euthanized.
The Indiana State Board of Animal Health says the egg-laying chickens are at a high risk of contracting the H7N8 virus because they're housed at one of the 10 farms in Dubois County with infected turkeys.
Crews already were working to euthanize more than 245,000 turkeys to prevent the virus' spread. With the added chickens, the outbreak will bring about the deaths of about 401,000 birds.
Officials also have also added a precautionary 6-mile "surveillance zone" beyond the 6-mile control area created last week around the first turkey farm where the virus was found.