DES MOINES, Iowa (AP) – Two more Iowa farms have tested positive for bird flu.

The Iowa Department of Agriculture says two northwest Iowa farms raising young chickens to eventually lay eggs likely have the virus. No estimate of numbers was immediately released for a farm in Sioux County, the 12th case in that county and one in Plymouth County, the first case there.

Iowa has 52 bird flu cases in 14 counties. Nearly 25 million chickens and 970,000 turkeys will die.

South Dakota announced Thursday its first chicken farm with 1.3 million egg layers. The state earlier found the virus on turkey farms.

Nebraska officials confirmed their second case, a chicken flock, and Minnesota reported two new cases.

The USDA lists 162 confirmed cases nationwide affecting more than 33 million birds.