MINNEAPOLIS (AP) - State and federal officials have announced the discovery of a deadly bird flu strain at eight more Minnesota turkey farms, raising the state's total to 22.

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.