Consumers who have unpasteurized, raw milk from Pool Forge Dairy should immediately throw it out and monitor themselves and their children for symptoms of Listeria infection for the next 70 days.

Pennsylvania’s Department of Agriculture posted the warning Monday because routine tests by the department showed the milk to be contaminated with Listeria monocytogenes. 

“Consumers who purchased raw, whole milk from Pool Forge Dairy between April 25 and May 7 should immediately discard it. The milk was sold in a plastic quart, half-gallon, and gallon containers with the Pool Forge label,” according to the notice from the agriculture department.

The dairy, which is Lancaster County, sold the implicated unpasteurized milk at the farm at 201 Bridgeville Road; Shady Maple Market at 1324 Main Street; and Hoover’s Farm Market at 1719 Main Street. All three locations are in East Earl Township in northeastern Lancaster County.

It can take up to 70 days after exposure for symptoms of Listeria infection to develop. Called listeriosis, the infection is particularly dangerous for young children, the elderly, pregnant women and anyone else with an underdeveloped or compromised immune system. 

In high-risk groups, particularly young children and people older than 65, the infection can quickly lead to life-threatening complications and death.

Listeriosis in pregnant women can result in miscarriage, premature delivery, a serious infection of the newborn, or stillbirth. 

As of Monday, no reported illnesses had been attributed to the implicated raw milk, but people who consumed the milk should consult their physicians if they become ill, according to Pennsylvania officials.

Pasteurization of milk kills Listeria monocytogenes and a variety of other pathogens, including bacteria, viruses, and parasites. These pathogens easily thrive in raw milk, even if it is kept refrigerated. Listeria can survive freezing for long periods of time, according to the federal Centers for Disease Control and Prevention.

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