The FDA and CDC, in collaboration with state and local partners, are investigating illnesses in a multi-year, multistate outbreak of Listeria monocytogenes infections linked to queso fresco and cotija cheeses manufactured by Rizo Lopez Foods, Inc., of Modesto, California.

This outbreak includes cases dating back to 2014 and is currently ongoing. CDC investigated this outbreak in 2017 and 2021. Epidemiologic evidence in previous investigations identified queso fresco and other similar cheeses as a potential source of the outbreak, but there was not enough information to identify a specific brand.

A sample of Rizo Bros Aged Cotija tested positive for Listeria monocytogenes during sampling conducted by the Hawaii State Department of Health’s Food and Drug Branch in January 2024. In response to that finding, Rizo Lopez Foods, Inc. voluntarily recalled one batch of Rizo Bros Aged Cotija Mexican Grating Cheese (8oz) on January 11, 2024. CDC and FDA reopened the investigation in January 2024 after new illnesses were reported in December 2023 and whole genome sequencing (WGS) analysis of the cotija cheese sample showed that it is the same strain of Listeria that is causing illnesses in this outbreak.

According to CDC, of the 22 people interviewed, 16 (73%) reported eating queso fresco, cotija, or other similar cheeses. Among people who remembered specific brands, three people who got sick between 2014 and 2022 reported Don Francisco brand queso fresco or cotija. Don Francisco is one of the brands of recalled cheeses.

FDA initiated an on-site inspection at Rizo Lopez Foods, Inc.  FDA’s inspection is still ongoing; however, an environmental sample collected during that inspection tested positive for Listeria monocytogenes. WGS analysis of that sample showed that it is the same strain of Listeria that is causing illnesses in this outbreak.

In response to this investigation, Rizo Lopez Foods, Inc. has voluntarily recalled all sell by dates of its dairy products. The recalled products include cheese, yogurt, and sour cream sold under the brand names Tio Francisco, Don Francisco, Rizo Bros, Rio Grande, Food City, El Huache, La Ordena, San Carlos, Campesino, Santa Maria, Dos Ranchitos, Casa Cardenas, and 365 Whole Foods Market. The firm has temporarily ceased the production and distribution of these products. while their investigation is ongoing.