Foods that May Be Contaminated with Listeria

Listeria is a bacterium that causes listeriosis illness in people as a result of eating contaminated food. The bacteria may contaminate raw or cooked food and are widely found in nature. It’s estimated that 1600 people get listeriosis each year and around 260 of them die. Pregnant women, older people, people with a weak immune system due to diseases and individuals under medication are at high risk of listeria infection. The common symptoms include fever, headache, tiredness, aches, and pain. The symptoms, if not attended to, may progress to illness such as meningitis and septicemia. Several researchers link listeria to waste, animal or human, used as fertilizer which flourishes in water.

Most farms use some type of waste as fertilizer thus increasing the chances of listeria spreading to their plants. The plants become contaminated with listeria when they touch the soil, mud or water that contain the bacteria. In order to be able to protect ourselves against listeriosis, we need to know the foods that are most likely to be contaminated.

All Sorts of Fruits

From melons to apples to papaya, all can pick up the listeria bacteria. Similarly, any sprayed or washed fruits with water containing listeria picked up from the soil can also carry the listeria bacteria. After a risk assessment by the FDA for listeria, it was discovered that more than 11 percent of all fruits sampled tested positive for listeria.

However, you should note that the listeria is on the outside of the fruits, meaning it doesn’t spread throughout the flesh. Therefore, avoiding certain fruits doesn’t help since statistically speaking the damage to your health outweighs the potential safety benefits. It’s safer to wash your fruits immediately after buying them and wash them again before eating. Also, wash the fruits even if you do peel it.

Canned and Raw Seafood

According to the FDA, while conducting a safety test on many types of food for listeria, smoked seafood surprisingly had the highest amount. Out of 7,855 samples, 12.9 percent contained listeria. Raw seafood and preserved fish also tested high. The only way to avoid listeria contamination, in this case, is by buying your smoked and canned fish from a reputable company. Additionally, avoid eating it cold and cook it with your dishes. If you have another way to avoid listeria, then follow it to guarantee your own safety. ”

Foods Refrigerated for a Long Time

Unlike most types of bacteria, listeria can continue to grow under refrigeration. Most people don’t realize that refrigerating food doesn’t stop listeria growth once introduced. Consuming ready-to-eat foods can be potentially harmful but cooking your food at high temperatures can kill listeria. Example of ready to eat food is cheese. Even worse, soft-ripened cheese and semi-soft cheese all tested higher for listeria than hard cheese. To avoid contamination, put your cheese into cooked dishes, but if you like cheese sandwich then there isn’t much to be done.

Root Vegetable

Ground grown vegetables like squash, beets, carrots, and potatoes can easily take up listeria in the soil. Also, vegetables that grow on low lying vines like zucchini can also be contaminated. However, this shouldn’t scare you into not eating veggies because they are the healthiest food in your diet. Focus on washing your veggies thoroughly and peel where appropriate. Remember to wash before and after peeling too since peeling doesn’t cut off listeria because the bacteria could be transferred onto your hands.

Smoked and Preserved Meat

The FDA listed hot dogs, salami, sausages and all types of preserved meats which are eaten cold to be potentially listeria culprits. After testing these foods, listeria was found to be 6.4 percent in sausages sampled, 4.8 percent in hot dogs sampled and 6.5 percent in pates and meat spreads. Just imagine how much listeria you’re eating from these preserved meats. As earlier said, cooking your meats before eating them can help reduce listeria contamination.


The number of outbreaks associated with listeriosis is reported to be increasing in the U.S. The good news is that listeriosis can be diagnosed using a laboratory test and can be treated with antibiotics. You can apply the same guidelines recommended to help prevent other foodborne illnesses and stop listeria contamination. The Coordinating Center for Infectious Diseases (CCID) is reported to have begun studying listeria in several states to help measure the impact of prevention activities and recognize trends in disease occurrence. The CCID is also assisting local health departments in investigating outbreaks. With early detection, doctors can help identify sources of infection and prevent more cases of the disease.

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