Bird flu hits two more Iowa turkey flocks

Two flocks of a total of 100,000 turkeys in Buena Vista and Cherokee counties were recently infected by a highly transmissible avian influenza, according to the Iowa Department of Agriculture and Land Stewardship.

The virus has been detected in five Iowa flocks just in the past week. That matches the highest rate of detection so far this year.

Wild, migrating birds are believed to be the primary sources of transmission. They can be asymptomatic, but the virus is often deadly for domestic birds. Entire flocks are culled to prevent the virus’ spread after an infection is detected, and the carcasses are destroyed.

The virus poses a low risk to humans, according to the U.S. Centers for Disease Control and Prevention.

The southern migration of birds in the Midwest is winding down, according to BirdCast, which uses radar to track their movement. Weekly waterfowl surveys by the Iowa Department of Natural Resources show the number of ducks in the state this year peaked in November and is waning. Geese migration in the state typically peaks this month. Both birds are known carriers of the virus.

The recent detections of the virus in the Buena Vista and Cherokee commercial turkey flocks — which had about 50,000 birds apiece — are the second for each county since October.

There have been a total of 29 known infected commercial and backyard flocks in the state this year, for a total of about 15.8 million birds. There were 19 detections during the wild birds’ northern migration earlier this year, and there have been 10 detections so far during the southern migration.

This article first appeared in the Iowa Capital Dispatch.