In this Sept. 17, 2021, file photo, a chicken stands watch in a coop at a farm in Penobscot. Credit: Robert F. Bukaty / AP

New cases of the highly contagious bird flu have been discovered in two more Maine counties.

There are two new confirmed cases in a backyard flock of 173 birds in York County, while two cases were also confirmed in a backyard flock of 70 birds in Lincoln County, according to the Maine Department of Agriculture, Conservation and Forestry.

Additionally, cases have been confirmed in two more large flocks in Knox County, where two reports were confirmed last month.

The Department of Agriculture, Conservation and Forestry said the risk of avian flu is high right now and has placed the properties under quarantine and have implemented safety measures.

Those safety measures include monitoring properties with domestic flocks and notifying bird owners of the importance of safety measures to help prevent disease.

Backyard flocks and commercial operators should keep their birds indoors to prevent the spread of the disease, but death is a primary indicator of the avian flu, according to Jim Britt, a spokesperson for the agriculture department.

Britt said there’s a low risk of avian flu for humans, and as long as poultry and eggs are cooked properly, food should be safe.

So far, nearly 7 million chickens and turkeys in the U.S. have been killed this year because of the virus.