The agency found H7N3 avian influenza, a virulent or highly pathogenic strain, in a turkey flock in Chesterfield County, South Carolina, according to a statement. No human cases of the virus have been detected and there is no immediate public health concern, the USDA said.
The worst-ever US outbreak of avian flu in 2014 and 2015 killed about 50 million birds, most of which were egg-laying hens in Iowa.