DES MOINES (AP) – Iowa agriculture officials said five additional commercial chicken farms show signs of the presence of bird flu and a backyard duck flock near a previously confirmed case also has tested positive.

The new chicken cases are on Sioux County farms. Two had a total of 200,000 chickens. Estimates were not immediately available for the remaining three farms. The backyard ducks are on a farm in O’Brien County.

The new cases raise Iowa’s total number to 34 cases in 11 counties.

About 21 million of Iowa’s chickens will be affected if the latest cases are confirmed. The number of turkeys to be lost is approaching 500,000.

More than 100 farms in the Midwest have the bird flu virus with more than 28 million birds affected.