The state Department of Agriculture found the illness in five separate flocks on farms in North Whitehall Township between Thursday, Nov. 3 and Wednesday, Nov. 9, according to a report by the Pennsylvania Farm Bureau, a private lobbying association.
The affected farms were not named, but the outbreak could impact up to 75,000 turkeys across all five flocks, the report says.
The Bureau said state officials will set up a "control area and surveillance zone" around the farm to manage and limit the spread.
Avian influenza or "bird flu" is a contagious virus that can cause serious illness and high mortality in livestock, says the Department.
A variant that officials call "Highly Pathogenic Avian Influenza" or HPAI was first detected in Pennsylvania in April among chickens on a Lancaster County farm, according to state officials, though it's not clear if the Lehigh County outbreak is connected.
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