A multistate, multi-year Listeria monocytogenes outbreak linked to requeson, a soft, ricotta-like cheese, has sickened eight people in three states, resulting in seven hospitalizations and one death.

The cheese was produced by Clover Hill Dairy LLC and affected products have been recalled. At this time, there is not enough evidence for the U.S. Food and Drug Administration (FDA) to determine if the recalled cheese can explain the entire outbreak.

According to information from the U.S. Centers for Disease Control and Prevention (CDC), clinical samples were collected between March 6, 2023 and May 9, 2026. Of the seven patients interviewed, five reported eating cheese, and two specifically identified Clover Hill Dairy-brand cheese. Illnesses have been reported in New York, Maryland, and Virginia.

On May 13, 2026, the Suffolk County Health Department (SCHD) notified the New York State Department of Agriculture and Markets (NYS AGM) of two related L. monocytogenes illnesses within one family who had purchased food from a local retailer in Brentwood, New York. The following day, the New York State Department of Health (NYS DOH) confirmed that both patients had consumed requeson cheese purchased at the Brentwood retailer. NYS AGM investigators tested five cheese samples collected from the retailer and found L. monocytogenes in one sample of requeson that had been repacked by the retailer. Whole genome sequencing (WGS) matched the strain of L. monocytogenes found in the requeson cheese to the clinical strain from the two New York patients who reported purchasing cheese from the Brentwood retailer.

On May 27, 2026, NYS AGM conducted an inspection at the retailer's cheese distributor, which identified Clover Hill Dairy LLC of Mechanicsville, Maryland as the requeson cheese manufacturer. A sample collected from an unopened 18-pound sealed bucket of requeson manufactured by Clover Hill Dairy also tested positive for L. monocytogenes. WGS analysis of this isolate is pending.

On June 3, 2026, Clover Hill Dairy issued a voluntary recall of its requeson/soft ricotta products.

The Maryland Department of Health has suspended Clover Hill Dairy’s operating license, issued a consumer advisory, and is conducting a follow-up evaluation in cooperation with the facility.