Raw chicken, pork, dodgy mussels, and clams have long been recognized as foods to be cautious with, but in a world of mass production, listeria contamination can extend far beyond these items. “We must be endlessly careful with all products in facilities prone to the deadly infection Listeria,” experts warn. Listeria, or listeriosis, is a serious infection caused by the bacterium Listeria monocytogenes, often found in soil, water, and animal feces.
The Centers for Disease Control and Prevention (CDC) highlights several foods that are common sources of listeria infection: deli meats, soft cheeses, smoked fish, pate, raw vegetables, and sushi. However, recent recalls have revealed that everything from ready-made salads to frozen dinners and even fruits and vegetables can also be tainted with listeria. This year alone, hundreds of contaminated products have been sold at major retailers like Walmart, Costco, Aldi, Kroger, and Target.
Though rare, listeria infections are serious, with nearly 30% of cases resulting in death. One recent listeria outbreak at Boar’s Head’s Virginia factory in the summer of 2024 left 59 people ill and 10 dead. The popular cold-cut company had to close the factory and now faces legal battles over the contamination. “Don’t ignore those recall warnings,” health officials caution.
While anyone can contract listeria, certain groups are at higher risk, including older adults and people with compromised immune systems. The CDC warns that listeria can cause invasive infections such as sepsis, meningitis, and meningoencephalitis. More rarely, the infection may spread to specific areas of the body, resulting in conditions like septic arthritis, osteomyelitis, or infections of the chest, abdomen, skin, and eyes.
Pregnant women are particularly vulnerable to listeriosis. Though the illness is often mild or even asymptomatic in mothers, it can lead to devastating outcomes for unborn children, such as miscarriage, stillbirth, preterm labor, or life-threatening infections like sepsis or meningitis.
Listeria can also manifest as a stomach bug, known medically as acute febrile gastroenteritis, but routine stool cultures won’t detect the bacteria. This makes it difficult to identify without clear symptoms or a confirmed outbreak in your area.
Outbreaks, though sometimes small, can be deadly. For instance, a 2022 outbreak in New York linked to deli meats and cheese sickened 12 people, with 11 of them reporting they had consumed deli products. In February 2024, a strain of listeria was discovered in open packages of deli meats such as mortadella, ham, and salami at a Brooklyn deli. More recently, in October 2024, the USDA issued a massive recall of 9.9 million pounds of meat—primarily chicken—found in hundreds of salad and frozen dinner products.
While avoiding meat may seem like a safeguard, listeria can also infect raw vegetables through contaminated soil or manure used as fertilizer. Even after thorough cleaning, bacteria can remain, especially if the vegetables pass through a facility with equipment already flagged for contamination.
Each year, an estimated 1,600 people in the U.S. contract listeriosis, and about 260 of those cases result in death. These numbers serve as a stark reminder to heed recall warnings and take listeria risks seriously.
