A Wisconsin company that has been supplying meat products to McDonalds restaurants for over three decades is recalling approximately 1,134 pounds of pork sausage patties that may be adulterated with Listeria monocytogenes, the U.S. Department of Agriculture’s Food Safety and Inspection Service (FSIS) announced this week.

The fully cooked pork sausage patties produced by Fair Oaks Farms, LLC, a Pleasant Prairie, on August 8, 2017, in 2-lb. plastic sleeve packages containing “BREAKFAST Best FULLY COOKED ORIGINAL PORK SAUSAGE PATTIES,” with a sell-by date of 05/15/2018 are subject to the recall.

The products bear establishment number “EST. 17479T” above the sell by date. These items were shipped to distribution and retail locations in Illinois, Iowa and Wisconsin.

According to the USDA’s inspection service, the problem was discovered when firm’s routine testing indicated positive results for Listeria monocytogenes. The products were on hold at a distribution center, however, the products were inadvertently shipped. There have been no confirmed reports of adverse reactions due to consumption of these products.

Consumption of food contaminated with L. monocytogenes can cause listeriosis, a serious infection that primarily affects older adults, persons with weakened immune systems, and pregnant women and their newborns. Less commonly, persons outside these risk groups are affected.

Listeriosis can cause fever, muscle aches, headache, stiff neck, confusion, loss of balance and convulsions sometimes preceded by diarrhea or other gastrointestinal symptoms.

FSIS and the company are concerned that some product may be frozen and in consumers’ freezers.

Consumers who have purchased these products are urged not to consume them.