An outbreak of bird flu at a second commercial egg facility in Jefferson County has led to euthanization of nearly one in five Wisconsin egg-laying chickens.

On Wednesday, the Wisconsin Department of Agriculture, Trade and Consumer Protection said that the 800,000-bird Jefferson County flock and an 87,000-turkey flock in Chippewa County have become the state's fourth and fifth cases of bird flu.

The Jefferson County facility is among the state's largest chicken farms. The birds that haven't died already will be euthanized.

The outbreak of the Jefferson County facility followed another 180,000-bird egg farm in Jefferson County, where the virus appeared on April 12. According to DATCP, the state is home to 5.4 million chickens that lay eggs. The two Jefferson County outbreaks affect nearly a million of them.

According to Hormel Foods Corp., the Chippewa County facility is owned by its Jennie-O Turkey Store division. The highly contagious H5N2 strain of the avian influenza virus has been in the flocks.

DATCP spokeswoman Raechelle Cline said that although, further testing will be required to confirm the strain, quarantine efforts move ahead immediately.

Another 53.1 million chickens are slaughtered for meat in Wisconsin. By euthanizing contaminated flocks, larger problem can be prevented in future.

Cline said mentioned that euthanization at the first Jefferson County facility is almost complete. About 1,000 chickens have been killed in carbon-dioxide containers each day, with about 10,000 to 15,000 remaining.

Cline added, "The containment methods haven't failed; we just don't really know how this is spreading. We are devoting as much as we can with regard to resources to make sure this happens in a timely manner".

Meanwhile, the state is telling poultry owners, including backyard chicken owners, to restrict access to their property. They are insisting them to keep birds away from other birds, keep hands and equipment clean, buy birds from reputable sources, avoid sharing equipment or supplies with neighbors or other bird owners, and check birds frequently.