Isolation and characterization of a low-pathogenicity H7N7 influenza virus from a turkey in a small mixed free-range poultry flock in Germany.

A hemagglutinating virus was isolated from a dead turkey in a small mixed free-range flock in Southern Germany. It was identified as influenza virus type A of subtype H7N7. The pathogenicity was low. An intravenous pathogenicity index of 0.03 was recorded, and the nucleotide sequencing revealed the amino acid sequence NVPEIPKGR*GLFG at the cleavage site of the hemagglutinin. Antibodies as well as virus were detected in the affected flock. Further virus spreading to other flocks was prevented by stamping out policy. Serological monitoring of contact flocks revealed one small backyard flock of 18 hens, which was positive. This flock was also destroyed. The origin of the virus could not be identified.