Rising H5N1 bird flu cases in the U.S. prompted the CDC to study the virus in ferrets, revealing it may have the potential to spread and cause severe symptoms in other mammals.

The new guidance comes after blood tests for 115 farmworkers in Michigan and Colorado showed that eight workers — or 7% — had antibodies that indicated previous infection with the virus

The Centers for Disease Control and Prevention (CDC) is updating its recommendations for testing, treatment and protection for workers who may be exposed to animals infected with bird flu. The update comes after the agency found evidence of dairy workers with positive antibodies,

About 7% of dairy workers exposed to the avian flu that is spreading through U.S. herds have become infected themselves, federal experts estimate. That number highlights concerns that circulating strains of bird flu might become highly infectious in humans,

Seven percent of tested workers on dairy farms where cows were infected with bird flu caught the virus themselves, according to a new study.