Good Biosecurity Practices Can Help Keep HPAI Out of Iowa Herds

By Grant Dewell & Sherry Hoyer

Avian influenza (HPAI) has been confirmed in dairy cattle in nine states to date. Yet, so far, there are no confirmed positive herds in Iowa.

This specific virus has been found in wild birds, which were the primary source of the virus in the Texas panhandle area. However, movement of dairy cattle is the most likely source of subsequent spread to other geographical areas.

It is believed that the virus is transmitted from cow to cow during milking, according to Grant Dewell, extension beef veterinarian with Iowa State University Extension and Outreach.

As of now, beef cattle have not been identified with the disease, and this is most likely due to the mammary gland being the primary involved tissue.

"Clinical signs of affected cows are reduced appetite and reduced milk production, as well as thickened and discolored milk," he said. "If you suspect HPAI in your cow herd, contact your veterinarian for appropriate diagnosis and testing."

There is no specific therapy for infected cattle, and most will recover on their own. Supportive care can be beneficial. There is no vaccine for HPAI in the United States.

"The virus has been transmitted to cats and, in two cases, a dairy worker, but transmission to humans is considered a low health risk," he said. "General personal protection such as gloves, coveralls and eye protection are recommended."

Dewell said good biosecurity practices should be implemented by beef producers to protect their herds.

If possible, minimize access of wild birds to cattle, and do not use unpasteurized colostrum or milk from dairy farms in your beef herds. If receiving new cattle, isolate those incoming animals for at least 21 days from your original herd.