Biological and molecular characterization of H13N2 influenza type A viruses isolated from turkeys and surface water.

The pathogenicity potential of two H13N2 influenza viruses, one isolated from turkeys and the other isolated from surface water, was evaluated in turkeys, chickens, and mallard ducks (Anas platyrhynchos) after intracranial and oculonasal inoculation. Both isolates replicated in turkey poults, causing depressed weight gain, morbidity and mortality; both also caused histopathological lesions, such as mild to severe pancreatitis, hepatitis, and nephritis in turkeys. These isolates replicated in mallard ducklings but not in chickens. There was depressed weight gain in ducklings given the H13N2 isolate from water. Neither isolate caused morbidity or mortality in ducklings or chicks after inoculation.