- Contaminated Food
- What Is It?
- Risk of Listeriosis
- Treatment Options
Foods that contain Listeria include the following:
- All animals’ meat, while still uncooked or undercooked
- Well-cooked ready-to-eat foods such as deli meats and hot dogs (while they undergo other processes such as slicing)
- Raw fish and shellfish
- Raw eggs
- Raw unpasteurized milk
- Cheese made from raw milk
- Unpasteurized dairy products
- Cream or custard
- Unwashed raw vegetables and fruits
- Uncooked pre-prepared foods such as sushi and sandwiches
- Other ready to eat foods
- Hummus and other dips that contain tahini
- Cold-cut meats
- Refrigerated meat pâté or spread
- Refrigerated smoked fish
- Soft serve ice-cream
How is food contaminated with Listeria?
Listeria bacterium, especially Listeria monocytogenes, can be found in soil and water.
- Vegetables and fruits can be polluted by soil or manure used as fertilizer.
- Animals can carry the germs without becoming unwell, and meat or dairy products derived from these animals can become infected.
- Bacteria have been detected in raw foods such as uncooked meats and vegetables, as well as processed goods that have become contaminated during processing, such as cheese and cold cuts at the deli counter.
- The bacterium may be present in unpasteurized (raw) milk or foods produced from raw milk.
- Listeria can infect other foods in the refrigerator through spillage, especially juices from the following:
- Hot dog
- Lunchmeat packages
- Raw meat
- Raw poultry
What is Listeria?
Listeria is a bacterium that is commonly found in soil, water, and refrigerators and even on your hands.
- Among all other species of Listeria, Listeria monocytogenes is the most predominant and highly virulent, which means it causes a serious infection that may even lead to death.
- Consumption of food contaminated with Listeria causes food poisoning.
- Listeriosis is an infection caused by the Listeria bacterium that leads to food poisoning.
Who are at a risk of listeriosis?
Although Listeria is present almost everywhere in your environment, your immune system fights off bacteria and prevents infection in your body from listeriosis (an uncommon infection).
Although healthy adults and children ingest Listeria-infected food, they do not become ill, but people who are prone to the disease will almost certainly become ill after they consume even a few bacteria.
The following people are more prone to listeriosis:
- People with weak immune systems, especially:
- Due to an infection such as human immunodeficiency virus infection where the immune system is disrupted.
- After taking immunosuppressants as a treatment of other medical conditions such as kidney or liver diseases and cancer
- Women who are pregnant and their unborn fetus and newborns:
- Pregnant women have weak immunity
- Listeria can transmit from the mother to her baby during pregnancy through the placenta (vertical transmission)
- Although it is believed that the mother may transmit Listeria through her breast milk, there is no strong evidence to support the statement
- People who are 65 years and older and who may have a weak immune system due to aging
What are the symptoms of listeriosis?
The incubation period—the time from being infected with the bacterium to the appearance of the first symptoms of Listeria monocytogenes—may range from four days to several weeks, which may go up to 70 days. Listeria that spreads to other parts such as the brain and placenta from the gut have longer incubation periods.
The most common symptoms of listeriosis may include:
- Flu-like symptoms
- Muscle and joint pain
Serious illness may cause the following:
- Septicemia (a life-threatening infection in the blood)
- Meningitis (inflammation in the outer covering layers that surround the brain)
- Encephalitis (infection of the brain)
- Neck stiffness
- High fever
- Extreme fatigue
- Pregnancy-related complications:
- Premature birth
How is listeriosis diagnosed?
Symptoms caused by Listeria bacterium, especially the most common symptoms, give the doctor a picture of possible food poisoning. However, to know the exact organism that caused food poisoning, bacterial culture has to be done.
Some body tissue such as the placenta or body fluids such as the blood and spinal fluid are collected and cultured in a lab to find the causative organism. After a while, bacteria that are grown on the culture media are studied under the microscope to identify the organism.
- CDC Warns of Potentially Fatal Bacterial Illness on U.S. Gulf Coast
- Helping Others as Volunteers Helps Kids 'Flourish': Study
- FDA Approves Pfizer's RSV Shot for Older Adults
- What to Do When Tough-to-Treat Lymphoma Strikes During Pregnancy
- Rate of Pregnant U.S. Women Who Have Diabetes Keeps Rising
- More Health News »
What are the treatment options for listeriosis?
If you are diagnosed with listeriosis, your doctor will prescribe you antibiotics to treat listeriosis. Early detection and treatment of Listeria in pregnant women is a must because they prevent the transmission of infection to the baby. Infected babies may be treated with antibiotics in appropriate doses.
However, even with quick treatment, some infections result in mortality. This is more likely among the elderly and people who have other major medical concerns.
How to prevent listeriosis
Avoiding high-risk foods and using hygienic food-handling procedures are the best ways to avoid Listeria infection.
- If you're going to cook something, cook it well.
- Before you consume fresh raw fruits and veggies, make sure to thoroughly wash them first.
- Cookware and utensils should be thoroughly cleaned.
- After handling raw foods, wash knives and cutting boards.
- Refrigerate raw items at the bottom of the fridge and check the temperature regularly.
- Refrigerate any leftovers right away. Throw them out if you don't eat them within 24 hours.
- If you do reheat them, make sure they're hot and steaming.
- Refrigerate frozen meats to thaw.
- Keep raw meat separate from vegetables, cooked foods, and ready-to-eat items in the fridge and while preparing food.
- Scrub the surface of melons such as cantaloupes, watermelon, or honeydew before cutting, and wash hands for 20 seconds before and after handling with warm water and soap.
- Direct contact with infected animals can lead to infection in veterinarians, farmers, and others who care with animals, so take precautions.
High-risk people and pregnant women should follow the suggested recommendations:
- It is not necessary to eliminate hard cheese, processed cheese, cream cheese, cottage cheese, or yogurt, but you should avoid soft cheese, such as:
- Mexican-style cheese
- Cook leftovers or ready-to-eat meals such as hot dogs until they are steaming hot before eating.
- Although the risk of listeriosis from deli counter foods is generally low, pregnant women and others with impaired immune systems may choose to avoid these meals or completely reheat cold cuts before consuming.
Health Solutions From Our Sponsors
Listeria (Listeriosis): https://www.cdc.gov/listeria/index.html
How does Listeria get into food? https://ask.usda.gov/s/article/How-does-Listeria-get-into-food
Listeria Infection (Listeriosis): https://mothertobaby.org/fact-sheets/listeriosis-pregnancy/
Top What Foods Contain Listeria Related Articles
Food PoisoningConcerned about food poisoning outbreaks? From ground beef to lettuce, many foods can cause them. Learn about foodborne diseases like Salmonella, E. coli, norovirus, Campylobacter, Staph, and hepatitis A.
Food PoisoningFood poisoning is common but can also be life-threatening. Food poisoning symptoms include stomach cramps, diarrhea, and vomiting. Read about different types of food poisoning, treatment, and tips for prevention.
Food Poisoning QuizWhat causes food poisoning? Can it be prevented? Take this quiz to learn about food safety and how to guard yourself against food poisoning.
Fungal Skin Infections: Types, Symptoms, and TreatmentFungal skin infections and fungal nail infections produce symptoms like red, itchy, circular rashes and thick, discolored, flaky nails. Fungal infection treatment may involve topical medication or oral antifungals.
How Do I Know If My Sore Throat Is Viral or Bacterial?It's seldom easy to tell the difference between bacterial and viral sore throats. Find out what the differences are and learn some tips for telling them apart. A sore throat is irritation and scratchiness in the throat accompanied by pain that often worsens with swallowing. The most common cause of a sore throat is a viral infection. Rarely, a bacterial infection can cause a sore throat. Antibiotics cannot treat a sore throat if it is caused by a viral infection. Viruses cause about 90% of sore throats; hence, antibiotics should not be used immediately as treatment for a sore throat. A doctor may prescribe antibiotics such as penicillin if a sore throat is caused by a bacterial infection.
How Do You Kill Bacteria in a Hot Tub?Hot tub folliculitis, also called jacuzzi folliculitis or spa pool folliculitis, is a skin condition arising within hours to a few days after bathing with warm water in a jacuzzi, spa pool or warm water swimming pool. The infection is generally caused by a bacterium called staph or staphylococcus aureus.
Mono (Infectious Mononucleosis)Infectious mononucleosis is a virus infection in which there is an increase of white blood cells that are mononuclear (with a single nucleus) "Mono" and "kissing disease" are popular terms for this very common illness caused by the Epstein-Barr virus (EBV).
Is Green Poop a Sign of Infection?Green poop may or may not be a sign of infection. The normal color of poop is brown, due to the bile pigment present in it. Any other color (green, red, black) needs attention. Abnormal colored poop may be due to changes in food habits, medicines or underlying medical causes.
Parasitic Infections: Worms People Can GetFind out about the types of worms that humans can get, how it happens, and what the symptoms and treatments are.
Salmonella Food PoisoningSalmonella infection (salmonellosis) is typically caused by the consumption of contaminated foods. Symptoms of salmonellosis include fever, vomiting, diarrhea, and abdominal pain. Salmonellosis typically resolves on its own in four to seven days. It's important to increase one's fluid intake to compensate for the fluid lost by vomiting and/or diarrhea.
What's a Virus?Is a virus alive? Learn the definition of a virus. Viral infections like COVID-19 can occur in your eyes, mouth, skin, or anywhere else. Should you use antibiotics to treat the flu? Is this STD a bacterium or a virus? Get the answers to the most common questions about viral infections.
What Are the 4 Types of Fungal Infection?The 4 most common types of fungal infections include athlete’s foot, ringworm, jock itch, and genital candidiasis.
What Are the 4 Types of Infections?Infection occurs when germs enter your body and multiply, resulting in disease. The four main types of infections are viral, bacterial, fungal, and parasitic.
What Is the Main Cause of Fungal Infection?The main cause of fungal infections are the result of compromised immunity (either local immunity over skin or systemic immunity in certain conditions).
When Is Green Poop a Sign of Infection?Green poop is a common issue, but sometimes it's a sign of infection. Learn green stool's signs, causes, and treatment options. Black poop is usually a common condition, but may signify underlying medical conditions.