Listeria outbreaks in the U.S. are rare compared to other forms of food poisoning, but food manufacturers and regulators take the potential of an outbreak seriously. For instance, Lipari Foods recently issued a voluntary recall of some of its pre-packaged sandwiches because they potentially contained listeria monocytogenes. The products included chicken salad and ham and cheese sandwiches under the Premo, Fresh Grab, and Lipari Old Tyme brand names. Lipari Foods distributed the sandwiches to retailers in 15 states, including Illinois. There were no reported illnesses connected to the recalled products as of the announcement of the recall on Oct. 8. A listeria infection, known as listeriosis, can be life-threatening, depending on the patient.

Those Most Vulnerable

Symptoms of listeriosis may appear as soon as a day after eating contaminated food or take weeks to develop. The severity of the symptoms depends on whether the infection has spread beyond the gut – known as invasive listeriosis – and may include:

• Fever
• Diarrhea
• Nausea
• Abdominal pain
• Muscle aches
• Stiff neck
• Loss of balance

Healthy adults rarely develop long-lasting illnesses from listeriosis, but the infection can be more serious for children, the elderly, and people with weakened immune systems. Patients with invasive listeriosis often require hospitalization, and about one in five patients die according to the Centers for Disease Control (CDC).

Listeria is a relatively rare yet potentially fatal form of food poisoning caused by bacteria in food. On average, about one in six people who contract listeria die from the symptoms. Listeria is often associated with foods such as:

• Raw milk;
• Soft cheese;
• Deli meats;
• Raw hot dogs;
• Raw spouts; and
• Smoked seafood.

However, there have been multiple incidents in recent years when listeria has been found in frozen vegetable packages.

Recent Outbreaks

Nature’s Touch Frozen Foods recently recalled its Signature Select Avocado Chunks because of potential listeria contamination. The product was sold in nine different store brands in 15 states, mostly in the western half of the U.S. The Centers for Disease Control previously investigated a listeria outbreak that started in 2013 and forced CRC Frozen Foods to recall all of its organic and frozen vegetables and fruits. Nine people were hospitalized and three of them died, though only one person was believed to have died from listeria. In 2018, nine people in Europe died from a listeria outbreak that was traced to a frozen vegetable brand distributed in 107 countries.

Cheese manufacturer Sargento recalled seven of its varieties of packaged cheese amid concerns of Listeria contamination. No cases of illness have been reported in conjunction with the cheese. The company recalled its cheeses after a Listeria outbreak was discovered at one of its suppliers' manufacturing plants. Its Ultra Thin Sliced Longhorn Colby and its Chef Blends Shredded Taco and Nacho Cheese varieties were flagged as being potentially contaminated. To contain any potential outbreak, Sargento also voluntarily recalled five other varieties manufactured at the same facility: Sliced Pepper Jack, Sliced Colby Jack, Off the Block Shredded Fine Cut Cheddar Jack, Off the Block Shredded Fine Cut Colby Jack, and Chef Blends Shredded Taco Cheese. Other cheeses produced at this facility were sold as Meijer's store brand, Sara Lee, and Amish Classics products.

Consuming food products contaminated with listeria can cause listeriosis, a type of food poisoning that can cause nausea, headaches, and diarrhea. When it spreads to the nervous system, it can cause the victim to suffer from joint aches, convulsions, and a loss of balance.

How Does Listeria Develop in Dairy Products?