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A listeria outbreak that has sickened at least 26 people in 11 states since 2014 has been linked to queso fresco and cotija cheese made by Rizo-López Foods, a California-based food supplier, federal public health officials said this week.

Though the outbreak was linked to just two types of cheese, Rizo-López Foods announced this week that it was voluntarily recalling all of its dairy products because of potential listeria contamination.

The products were distributed nationwide and sold under the brand names Tio Francisco, Don Francisco, Rizo Brothers, Rio Grande, Food City, El Huache, La Ordena, San Carlos, Campesino, Santa Maria, Dos Ranchitos, Casa Cardenas and 365 Whole Foods Market. The products, which have various sell-by dates through July 1, were also available at deli counters, the company said.

Of the 26 people who fell ill as a result of the outbreak, 23 were hospitalized and two died, according to the Centers for Disease Control and Prevention, which began its investigation in 2017. Cases were reported in Washington, Oregon, California, Nevada, Arizona, Colorado, Texas, Tennessee, North Carolina, Georgia and Florida.

Listeria bacteria can contaminate many foods. When ingested, they are most harmful to people who are pregnant, people who are at least 65 years old or those who have weakened immune systems. Listeria infection is the third leading cause of death from food-borne illness in the United States, according to the C.D.C.

The agency investigated the outbreak in 2017 and 2021, identifying “queso fresco and other similar cheeses” as a potential source, but it did not have evidence to tie the outbreak to a specific brand. The investigation was reopened last month after additional illnesses were reported in December, and officials found the bacteria strain from the outbreak in a cheese sample from Rizo-López Foods.

Two of the people sickened in the outbreak were pregnant, and one lost the pregnancy, according to the investigation. Two others who fell ill were newborns. The median age of those who fell ill was 52. Fifty-eight percent of those who were sickened were female and 71 percent were white.

The C.D.C. noted that the number of cases was probably higher than 26 and that people might have been sickened in states other than those listed.

“This is because some people recover without medical care and are not tested,” the agency said. “In addition, recent illnesses may not yet be reported as it usually takes three to four weeks to determine if a sick person is part of an outbreak.”

The agency encouraged people to avoid eating any of the recalled products, and to clean their refrigerators and surfaces that might have come into contact with the recalled foods. Officials are encouraging people to seek medical attention if they have listeria symptoms, which include fever, muscle aches, fatigue and headaches.

Several listeria outbreaks were reported in 2023, including ones tied to leafy greens, ice cream and peaches, nectarines and plums.