More than 16,000 Americans fall sick and 260 of them die every year after contracting the fatal food borne infection, Listeriosis. The Food and Drug Administration (FDA) has recently announced four new food product recalls due to possible Listeria contamination. The four food companies included in this new recall are Kashi Company, Zupan’s Markets, Essential Foods Inc. and HelloFresh.

In the US, one in five people with Listeriosis die, and this is the third leading cause of death through food poisoning. About 90% of the deadly Listeria food poisoning occurs in vulnerable groups such as newborns, older adults, pregnant women and individuals with weak immune systems i.e. HIV/AIDS, cancer, diabetes, kidney disease, and transplant patients . In pregnant women, Listeria can lead to fever and then miscarriage while in young children it can even cause meningitis. Despite several measures and precautions taken by the food authorities and companies to prevent food contamination by bacterium Listeria monocytogenes, multiple Listeria outbreaks and recalls are recorded each year in the country.

Listeria “can become dominant and be shed into the food,” said Rick Holley, a University of Manitoba food safety expert. “Sometimes, certain areas in some of these plants can build up these bacteria.”

The four new recalls announced by the FDA encompass a variety of different food products. Kashi company recall is due to sunflower seed pollution while the other three recalls are due to infected peas.  The brand ‘Kashi Go Lean and Bear Naked’ snack bars and granolas were previously recalled for a Listeria contamination and the new announcement was about amending the date codes of its products. According to Kashi, their bars contain sunflower seed from ‘SunOpta’ and the supplier source was found to be contaminated with Listeria.

On the other hand, Zupan Foods voluntarily recalled their Zupan’s Markets Macaroni Salad with Cheddar Cheese, after they found the frozen green peas used in the product were potentially contaminated with Listeria. Similarly the ‘HelloFresh’ frozen peas have been listed by the FDA after their supplier notified that they were infected. Similarly,the ‘Globespun’ Flavored Wraps by Essential Foods Inc. were voluntarily recalled as a result of tainted peas.

Listeriosis is also a major burden on the US economy and the United States Department of Agriculture (USDA) estimates the food borne illness costs more than $2.8 billion every year. The bacterium Listeria can be found naturally in the environment i.e.  in soil, water, decaying vegetation, and the intestines of animals. Food products get contaminated with Listeria when they are processed, packaged or handled in an unsanitary way.

Listeria is ‘ubiquitous’ i.e., it is present everywhere but its low numbers don’t pose a health risk. Sometimes Listeria concentrations can build up and its high concentration in food processing plants can lead to contamination of foods. The food products are then packaged and shipped to other places where they leads to further contamination.

Keep in mind that Listeria bacterium is quite different from other species and it can grow and spread even in a refrigerator and can cross-contaminate other foods. On the other hand,  other bacteria such as E. coli and Salmonella cannot survive in the cold temperature.

The USDA remarks that “Listeria can grow at refrigerator temperatures (40 ˚F or below).”

The FDA Consumer Update states that, “if you unknowingly refrigerate Listeria-contaminated food, the germs not only multiply at the cool temperature, they could contaminate your refrigerator and spread to other foods there, increasing the likelihood that you and your family will become sick.”

This is not the first case of multiple Listeria recalls in the US during 2016. Previously in April and May, millions of packaged frozen fruits and vegetables were recalled from 50 states. It was the biggest food recall due to Listeria in recent memory and more than 400 frozen products from the single source CRF Frozen Foods in Pasco, Washington were found to be contaminated. The Listeria containing frozen products were provided to 40 different brands including Costco, Target, Trader Joe’s and Safeway and so on. A total of eight people were found to be sick with Listeriosis and two passed away in the hospital.

So far, no illnesses have been reported in case of the new recalls. It is believed that this may be due to the cooking procedures. If contaminated peas or foods containing ingredients made from peas are properly cooked, it greatly lessens the degree of pathogenicity of Listeria. Proper washing, cooking and pasteurization of foods can kill Listeria. On consumption though, some healthy individuals may have suffered from a few short-term symptoms such as high fever, severe headache, stiffness, nausea, abdominal pain and diarrhea.