Officials are investigating after detecting influenza in 11 pigs recently exhibited at a fair in Frederick.
The Maryland Department of Agriculture said in a statement Sunday preliminary tests show the 11 pigs from The Great Frederick Fair are infected with influenza A. It isn't clear if that strain is potentially transmissible to humans, and additional testing is being conducted.
The statement says all swine at the fairgrounds are under a quarantine.
The discovery comes after pigs at a fair in Charles County were recently diagnosed with swine flu.
After that diagnosis, Maryland's Secretary of Agriculture issued an order canceling all pig activities at the St. Mary's and Calvert county fairs. That order remains in effect, but the department says all other activities involving swine can proceed as usual.