Federal health authorities have issued a public health warning concerning two types of frozen pasta meals available at Walmart and Trader Joe’s, due to potential contamination with a harmful bacteria.

The US Department of Agriculture (USDA) reported on Thursday that the Marketside Linguine with Beef Meatballs & Marinara Sauce, found in Walmart locations across the United States, has tested positive for Listeria monocytogenes. This bacterial strain was responsible for a dangerous outbreak earlier this summer.

This ready-to-eat product is packaged in a 12-ounce see-through plastic tray and contains establishment numbers ‘EST. 50784’ and ‘EST. 47718’ within the USDA inspection label.

Affected products have best-by dates of September 22, 24, 25, 29, 30, and October 1, 2025, according to the warning.

On Friday, the USDA’s Food Safety and Inspection Service (FSIS) broadened the alert to include the Trader Joe’s Cajun Style Blackened Chicken Breast Fettuccine Alfredo.

The frozen meal is sold in 16-ounce trays with establishment number ‘P- 45288’ and best-by dates of September 20, 24, and 27, 2025. 

Trader Joe’s said stores in California, Arizona, Nevada, New Mexico, and Utah may be affected.

‘We are issuing this guidance in an abundance of caution because testing of another brand with a shared ingredient source indicated this product may have the potential to be contaminated with Listeria monocytogenes,’ Trader Joe’s said in a statement on its website.

However, no illnesses linked directly to the two products have been reported, and no recall has been issued. 

FreshRealm, the company that manufactures the Walmart linguine meal, said tests confirmed the presence of Listeria monocytogenes in the beef meatball pasta.

‘FreshRealm held beef meatball marinara linguine meals after they tested positive for the outbreak strain,’ the CDC said Friday.

In its own statement, FreshRealm said, ‘We have long maintained that the source of the listeria was likely an ingredient supplied by a third party.’ 

The ‘contaminated’ ingredient is believed to be linguine pasta sourced from Nate’s Fine Foods of Roseville, California, according to the FSIS warning.

As part of the investigation, one of the manufacturers collected samples of the pre-cooked pasta used in the meals. Tests confirmed contamination with listeria, and further analysis is underway to determine if the strain is genetically linked to the earlier outbreak.

The USDA has since confirmed that the meals may contain the same listeria strain associated with an earlier outbreak tied to chicken fettuccine Alfredo sold at Walmart and Kroger stores – the outbreak resulted in four deaths and at least 20 reported illnesses. 

Listeriosis, the illness caused by Listeria monocytogenes, can lead to severe and sometimes fatal infections, especially in pregnant women, newborns, older adults, and people with weakened immune systems. 

Symptoms include fever, muscle aches, headache, stiff neck, confusion, and convulsions. 

According to the CDC, about 1,600 people contract listeriosis each year in the U.S., and approximately 260 die.

Federal officials are now urging consumers not to eat the affected meals. 

‘Consumers who have purchased these products are urged not to consume them. These products should be thrown away or returned to the place of purchase,’ the FSIS warning states.

Walmart has removed the affected meals from its stores, following guidance from FreshRealm earlier this week. 

Trader Joe’s is offering full refunds to customers who purchased the impacted fettuccine Alfredo.

FSIS says more products could be identified as the investigation continues and is advising consumers to monitor updates on its website.