State and federal officials have discovered a deadly bird flu strain at eight more Minnesota turkey farms — seven of them with ties to Jennie-O Turkey Store.

This raises the state’s total to 22 incidents, and 14 have ties to Jennie-O, a subsidiary of Hormel Foods Corp.

The eight farms have a combined 542,500 turkeys. Minnesota producers had already lost 910,000 birds to the disease since early March. This pushes the state’s total losses to nearly 1.5 million birds.

The new cases of the H5N2 virus include three counties where the disease had not turned up before, including two farms in Swift County with a combined 314,000 turkeys, and the first farms in Le Sueur and Redwood counties.

The affected farms have been quarantined and the remaining birds on them will be killed to contain the disease.

State Veterinarian Bill Hartmann expects more farms to be hit before the threat recedes.

Bird flu hits Iowa

The flu strain that has already led to the deaths of nearly 2 million turkeys nationwide spread to an Iowa turkey farm, authorities said on Tuesday, bringing to six the number of states hit with the outbreak.

The announcements on Tuesday came a day after confirmation of the first case of the virus in Wisconsin, the first case of a U.S. commercial chicken farm where the strain was detected, according to the U.S. Department of Agriculture.

Scientists believe domestic poultry are getting the highly-contagious H5N2 virus from wild migratory waterfowl but they are puzzled by the accelerating spread despite reinforced biosecurity measures at poultry production and processing facilities.