It follows outbreaks last month in Germany, the Netherlands and the UK.
Reports were submitted to the World Organisation for Animal Health from both countries yesterday (16 December).
In Italy, the outbreak was discovered in Veneto, Porto Viro, with close to 32,000 birds at risk.
While in the US, both the H5N8 and H5N2 strains have been discovered in Whatcom County, Washington, in wild birds.
A captive wild gyrfalcon, which had been fed hunter killed wild birds was found to have the H5N8 strain, while a wild pintail duck was found to have the H5N2 strain - the same as has been found in poultry farms in British Columbia, Canada in recent weeks.
The report stated that neither virus strains have been found in any poultry in the United States, and that the current detections involved only wild birds.