An outbreak of Listeria has prompted a massive cheese recall in the northeastern U.S.
The affected products are reportedly contaminated with Listeria monocytogenes, a disease-causing bacterium in the Listeria family that comes from unsanitary production conditions. The bacteria can survive and even grow under refrigeration, and easily spreads to other foods and surfaces. It can also be spread by pets who eat food contaminated with the bacteria. While it is usually killed by the process of pasteurizing milk, soft cheeses made from pasteurized milk can still be contaminated with listeria after pasteurization.
Listeria monocytogenes causes a disease called listeriosis. Symptoms appear anywhere from the same day to 10 weeks after exposure, but typically begin within two weeks. Symptoms of a mild infection include fever, muscle aches, nausea, tiredness, vomiting, and diarrhea, lasting between 1 and 3 days; a more severe infection is characterized by headache, stiff neck, confusion, loss of balance, and convulsions. A listeriosis infection can be life-threatening for pregnant women, infants and young children, the elderly, and individuals with compromised immune systems.
The FDA and state partners in Maryland and New York collected samples of the requeson cheese after two family members in New York were infected with listeria after purchasing food from a retailer in New York. New York state health officials conducted further tests and connected the infected cheese and connected it from the retailer to the distributor to the manufacturer: Clover Hill Dairy, in Mechanicsville, Maryland. Clover Hill voluntarily recalled its requeson products on June 3.
Whole genome sequencing identified 9 individuals who had been infected with Listeria, including one who died from the infection in 2023. The FDA said those cases were spread across Maryland, Virginia, and New York, and counted 8 hospitalizations of the 9 cases.
The types of cheeses affected by the recall include soft and semi-soft varieties, including Cujada and Ricotta/Requeson; mild cheese varieties, including cheddar, Colby, and Monterey Jack; hard cheddar and Colby cheeses; smoked cheddars; flavored cheeses—horseradish and Old Bay cheddar; pepper cheeses, jalapeño cheddar and pepper jack; smoked jalapeño cheddar, and variety packs.
One of Clover Hill Dairy's distributors, Nelson & Isa Lacteos of Bay Shore, New York, also instituted a recall of requeson in 1-pound clamshell packs.
The mandatory recall applies to soft ricotta and requeson distributed between May 4 and May 30 in North Carolina, Virginia, Maryland, the District of Columbia, New Jersey, and New York. The Nelson & Isa Lacteos requeson recall applies to retail stores in New York between May 15 and May 28.
The Maryland Department of Health suspended Clover Hill Dairy's operating license on May 30 in connection with the outbreak and is conducting a follow-up investigation.
Officials instructed retailers, restaurants, and consumers to dispose of any cheese products from Clover Hill Dairy. The manufacturer's plant number is 24-128.