Sources of listeria

Listeria (Listeriosis) | FDA

Listeria monocytogenes (L. monocytogenes) is a species of pathogenic (disease-causing) bacteria that can be found in moist environments, soil, water, decaying vegetation and animals, and can survive and even grow under refrigeration and other food preservation measures. When people eat food contaminated with L. monocytogenes, they may develop a disease called listeriosis.

L. monocytogenes is generally transmitted when food is harvested, processed, prepared, packed, transported or stored in environments contaminated with L. monocytogenes. Environments can be contaminated by raw materials, water, soil, and incoming air. Pets can also spread the bacteria in the home environment if they eat food contaminated with L. monocytogenes.

Symptoms

There are a range of symptoms for listeriosis. Depending on the severity of the illness, symptoms may last from days to several weeks. Mild symptoms may include a fever, muscle aches, nausea, vomiting, and diarrhea. If the more severe form of listeriosis develops, symptoms may include headache, stiff neck, confusion, loss of balance, and convulsions. For the very young, the elderly, and the immune-compromised listeriosis can result in death.

People infected with L. monocytogenes may start to see symptoms in a few hours or as long as two to three days after eating contaminated food. More severe forms of listeriosis may take anywhere from three days to three months to develop.

Due to the range in severity of illness, people should consult their health care provider if they suspect that they have developed symptoms that resemble a(n) L. monocytogenes infection.

At-Risk Groups

The severity of listeriosis varies and in some cases can be fatal, especially among the elderly, people with weakened immune systems or chronic diseases.

Listeriosis can be particularly dangerous for pregnant women and their newborn babies, leading to serious complications with their pregnancy, including miscarriage and stillbirth. Babies born with a listeriosis infection may develop severe health complications that require immediate medical attention, lead to lifelong health problems, or result in death. Women who suspect they have symptoms of listeriosis (muscles aches, nausea, stiffness in neck, headaches, etc.) should seek medical care immediately and tell their health provider what they ate. Learn more about People at Risk of Foodborne Illness.

Foods Linked to U.S. Outbreaks of Listeriosis

Past listeriosis outbreaks in the U.S. have been linked to raw, unpasteurized milks and cheeses, ice cream, raw or processed vegetables, raw or processed fruits, raw or undercooked poultry, sausages, hot dogs, deli meats, and raw or smoked fish and other seafood. L. monocytogenes has also been found in raw pet food.

Preventing Foodborne Illness at Home

The longer ready-to-eat refrigerated foods contaminated with L. monocytogenes are stored in the refrigerator, the more opportunity this pathogen has to grow. To slow down or prevent the growth of L. monocytogenes, set the refrigerator to 40 degrees Fahrenheit (4 degrees Celsius), and the freezer to 0 degrees Fahrenheit (-18 degrees Celsius).

Consumers should also follow these simple steps:

Wash the inside walls and shelves of the refrigerator, cutting boards and countertops, and utensils that may have contacted contaminated foods; then sanitize them with a solution of one tablespoon of chlorine bleach to one gallon of hot water; dry with a clean cloth or paper towel that has not been previously used.
Wipe up spills in the refrigerator immediately and clean the refrigerator regularly.
Wash hands with warm water and soap for at least 20 seconds before and after handling food and following any cleaning and sanitation process.
Pregnant women, the elderly and those with weakened immune systems should avoid certain foods, including unpasteurized or raw milk, cheeses made from unpasteurized milk, raw fish raw sprouts and some other raw foods, which carry a high risk for L. monocytogenes.
People with pets should take special care to avoid cross-contamination when preparing their pet’s food. Be sure to pick up and thoroughly wash food dishes as soon as pets are done eating, and prevent children, the elderly, and any other people with weak immune systems from handling or being exposed to the food or pets that have eaten potentially contaminated food.
Consumers can also submit a voluntarily report, a complaint, or adverse event (illness or serious allergic reaction) related to a food product.

Advice for Restaurants and Retailers

Retailers and/or other food service operators who have handled recalled or other potentially contaminated food in their facilities should:

Contact their local health department and communicate to their customers regarding possible exposure to L. monocytogenes.
To prevent the growth of L. monocytogenes, set the refrigerator to 40 degrees Fahrenheit (4 degrees Celsius), and set the freezer to 0 degrees Fahrenheit (-18 degrees Celsius).
Wash the inside walls and shelves of the refrigerator, cutting boards and countertops, and utensils that may have contacted contaminated foods; then sanitize them with a solution of one tablespoon of chlorine bleach to one gallon of hot water; dry with a clean cloth or paper towel that has not been previously used.
Wash and sanitize display cases and surfaces used to potentially store, serve, or prepare potentially contaminated foods.
Wash hands with warm water and soap following the cleaning and sanitation process.
Conduct regular frequent cleaning and sanitizing of cutting boards and utensils used in processing to help minimize the likelihood of cross-contamination.

Unlike most bacteria, L. monocytogenes can grow at refrigeration temperatures and freezing will not eliminate or reduce the pathogen. The FDA recommends that retailers implement time and temperature controls to reduce the opportunity for the growth of L. monocytogenes. L. monocytogenes can also cross-contaminate other food that has been cut and served on the same cutting board or stored in the same area. Retailers should check with your state for specific guidance. More information can be found in the FDA Food Code 2017.

Additional Information

Listeria (CDC)
FDA Food Code 2017
Keep Listeria Out of Your Kitchen
Preventing Listeria Infections: What You Need to Know
Environmental Assessments from Foodborne Illness or Contamination Events
FDA Issues Country-Wide Import Alert for Enoki Mushrooms from the Republic of Korea (July 2022)

Who to Contact

To report a complaint or adverse event (illness or serious allergic reaction), you can

Call an FDA Consumer Complaint Coordinator if you wish to speak directly to a person about your problem.
Complete an electronic Voluntary MedWatch form online.
Complete a paper Voluntary MedWatch form that can be mailed to FDA.

Visit www.fda.gov/fcic for additional consumer and industry assistance.

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Food Safety for Pregnant Women

Listeria infection (listeriosis) - Symptoms and causes

Overview

Listeria infection is a foodborne bacterial illness that can be very serious for pregnant women, people older than 65 and people with weakened immune systems. It's most commonly caused by eating improperly processed deli meats and unpasteurized milk products.

Healthy people rarely become ill from listeria infection, but the disease can be fatal to unborn babies, newborns and people with weakened immune systems. Prompt antibiotic treatment can help curb the effects of listeria infection.

Listeria bacteria can survive refrigeration and even freezing. So people who are at higher risk of serious infections should avoid eating the types of food most likely to contain listeria bacteria.

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Symptoms

If you develop a listeria infection, you might have:

Fever
Chills
Muscle aches
Nausea
Diarrhea

Symptoms might begin a few days after you've eaten contaminated food, but it can take 30 days or more before the first signs and symptoms of infection begin.

If the listeria infection spreads to your nervous system, signs and symptoms can include:

Headache
Stiff neck
Confusion or changes in alertness
Loss of balance
Convulsions

Symptoms during pregnancy and in newborns

During pregnancy, a listeria infection is likely to cause only mild signs and symptoms in the mother. The consequences for the baby, however, can be devastating — the baby can die in the womb or have a life-threatening infection within a few days of being born.

Signs and symptoms of a listeria infection in a newborn can be subtle, but can include:

Little interest in feeding
Irritability
Fever
Vomiting
Difficulty breathing

When to see a doctor

If you've eaten a food that's been recalled because of a listeria outbreak, watch for signs or symptoms of illness. If you have a fever, muscle aches, nausea or diarrhea, contact your doctor. The same goes for illness after eating a potentially contaminated product, such as foods made with unpasteurized milk or poorly heated hot dogs or deli meats.

If you have a high fever, severe headache, stiff neck, confusion or sensitivity to light, seek emergency care. These signs and symptoms can indicate bacterial meningitis, a life-threatening complication of a listeria infection.

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Causes

Listeria bacteria can be found in soil, water and animal feces. People can get infected by eating the following:

Raw vegetables that have been contaminated from the soil or from contaminated manure used as fertilizer
Contaminated meat
Unpasteurized milk or foods made with unpasteurized milk
Certain processed foods — such as soft cheeses, hot dogs and deli meats that have been contaminated after processing

Unborn babies can contract a listeria infection from the mother.

Risk factors

Pregnant women and people who have weak immune systems are at highest risk of contracting a listeria infection.

Pregnant women and their babies

Pregnant women are much more susceptible to listeria infections than are other healthy adults. Although a listeria infection might cause only a mild illness in pregnant women, consequences for their babies can include:

Miscarriage
Stillbirth
Premature birth
A potentially fatal infection after birth

People who have weak immune systems

This category includes people who:

Are older than 65
Have AIDS
Are receiving chemotherapy
Have diabetes or kidney disease
Take high-dose prednisone or certain rheumatoid arthritis drugs
Take medications to block rejection of a transplanted organ

Complications

Most listeria infections are so mild they can go unnoticed. However, in some cases, a listeria infection can lead to life-threatening complications, including:

Generalized blood infection
Inflammation of the membranes and fluid surrounding the brain (meningitis)

Prevention

To prevent a listeria infection, follow simple food safety guidelines:

Keep things clean. Wash your hands thoroughly with warm, soapy water before and after handling or preparing food. After cooking, use hot, soapy water to wash the utensils, cutting boards and other food preparation surfaces.
Scrub raw vegetables. Clean raw vegetables with a scrub brush or vegetable brush under plenty of running water.
Cook your food thoroughly. Use a food thermometer to make sure your meat, poultry and egg dishes are cooked to a safe temperature.

Precautions for people particularly at risk

If you're pregnant or you have a weak immune system, be particularly cautious about listeria. Take additional precautions with these types of foods:

Soft cheeses and Mexican-style cheeses. Don't eat soft cheeses such, as feta, brie, Camembert or blue cheese, or Mexican-style cheeses such as queso blanco and queso fresco, unless it's clear from the packaging that the product was made using pasteurized milk.
Hot dogs and deli meats. Avoid these unless they're reheated until steaming hot. Keep fluid from hot dog packages away from other foods, utensils and food preparation surfaces. Wash your hands after handling these products.
Meat spreads. Don't eat refrigerated meat spreads. Canned or shelf-stable — meaning they can be safely stored at room temperature — meat spreads are acceptable. Refrigerate after opening.
Smoked seafood. These products can be labeled as nova style, lox, kippered or jerky. It's OK to eat them in cooked dishes. Canned or shelf-stable smoked seafood is acceptable.
Raw or lightly cooked sprouts. Cook sprouts of any kind thoroughly.

By Mayo Clinic Staff

Associated Procedures

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Listeriosis: Causes, Symptoms, Treatment | doc.ua

Listeriosis is a disease that begins when Listeria monocytogenes enters the body. The disease is quite serious - in 30% of cases, listeriosis is fatal, so it is very important to know how to protect yourself from it. Listeriosis can develop in a few days or two months.

Attention!

Here you can choose a doctor who treats Listeriosis If you are not sure about the diagnosis, make an appointment with a general practitioner or general practitioner to clarify the diagnosis. nine0005

Causes

Usually, the listeriosis pathogen enters the body along with contaminated foods, as a result of which it enters the spleen, liver, lungs, lymph nodes and nervous system through the blood or lymphatic vessels. This is how foci of necrosis appear in the body, which are called listeriomas. Listeriosis in humans develops depending on the strength of the immune system, which is why severe brain damage can be observed mainly only in infants and immunocompromised patients. nine0005

Listeriosis can be contracted:

through poorly cooked meat or root crops. The danger is fraught with soft cheeses and meat products that are in vacuum packaging;
while caring for a patient with listeriosis;
by inhaling dust in rooms where skins are dressed or animal wool is processed;
due to an insect bite, more often a tick;
sexually;
due to transplantation of internal organs, mainly kidneys. nine0018

Workers in poultry farms and farms are most at risk of contracting this disease, so you should be very careful about safety in such work.

Symptoms

As you know, the sooner the disease is detected, the easier it is to cure the patient. And therefore, in order to successfully cure listeriosis, the symptoms should be known now: this will help to identify the disease faster.

Analysis for listeriosis can reveal four forms of the disease: glandular (which, in turn, has anginal-glandular and oculo-glandular variants), gastroenteric, nervous and septic. nine0005

Glandular:

Anginal:
- high temperature;
- general intoxication of the body;
- signs characteristic of angina;
- enlargement of the spleen and liver.
Eye variant:
- narrowing of the slits of the eyes;
- blurred vision;
- Conjunctivitis: unilateral purulent, with burning sensations in the eyes, redness of the eyes and copious flow of tears.

Gastroenteric:

very rapid temperature increase, up to 40 degrees;
headache;
severe chills;
pain in joints and muscle tissue;
vomiting and nausea, cramping abdominal pain, loose stools;
impurities of blood and mucus in the feces.

This form of the disease is also characterized by the fact that the development of infectious-toxic shock is possible.

Nervous:

high temperature;
severe headache (increasing), loss of consciousness;
muscle spasms.

Listeriosis in pregnant women is scary with this form, because it is very typical for newborns, to whom the disease can be transmitted from their mother. Moreover, the fetus can become infected with this disease both during gestation and during childbirth. Infection of the fetus threatens many: this is a spontaneous abortion, and the birth of a dead child, and the birth of a child who will have any malformations. With all this, congenital listeriosis threatens with a high risk of death and is considered one of the most severe options for the development of an infectious disease. nine0005

At the same time, the clinical manifestations of the congenital disease are not specific. It can be a high fever or a change in the pulse, impaired appetite (the child refuses to feed), vomiting, "cyanosis" of the skin, nodular rash (tubercles), jaundice, meningitis, general lethargy and lethargy.

Septic:

frequent chills;
changes in body temperature;
rash - large elements in the area of the joints, on the face in the form of a butterfly; nine0018
frequent pneumonia, jaundice and hepatitis.

Listeriosis is insidious, the diagnosis of the septic form is the most difficult, since in this form the disease develops extremely slowly. The septic form can begin with the fact that it will cut in the eyes and tickle in the throat. Also, this form is most common in newborns and people with weakened immune systems.

Chronic

Chronic disease is also possible. In this case, the pathogen can be in the body for a very long time and will not show any clinical symptoms. Only occasionally can listeriosis exacerbate: mild flu-like illnesses or chronic pyelitis in an exacerbated form. nine0005

Diagnosis

Symptoms of listeriosis are very similar to those of many other diseases. It is for this reason that listeriosis is usually diagnosed through laboratory diagnostics. There is a bacteriological method: it is aimed at isolating Listeria from the blood, a smear of the vagina, tonsils is taken.

Polymerase chain reaction or PCR is also performed. It is aimed at detecting sections of the DNA of the causative agent of the disease. Serological diagnostics is carried out to determine the immunoglobulin in human serum. nine0005

Treatment

Listeriosis is a serious disease and is often treated with hospitalization, although patients with glandular disease are treated on an outpatient basis. Listeriosis is treated with antibiotics. If there is severe intoxication, as well as dehydration, then during inpatient treatment, the patient is administered saline solutions intravenously. Symptomatic therapy is also carried out, for example, a patient with listeriosis with an ocular-glandular variant of the glandular form needs the treatment of conjunctivitis. nine0005

Never self-medicate listeriosis. It is imperative to contact the infectious disease doctor so that he clarifies the origin of the disease in this particular case and selects the appropriate therapy for this particular case.

Prevention

If you want to drink milk or eat meat, make sure that these products are subjected to heat treatment without fail. Be sure to follow the rules of hygiene and sanitation if you work in enterprises where animal carcasses are processed, as well as if you work in poultry farms or meat processing plants. nine0005

Careful sanitary control is also required, aimed at products that enter the store shelves.

Complications

This disease brings a number of consequences and complications to the unfortunate owner.

Since listeriomas form in the tissues of the central nervous system, they can lead to the development of meningitis, as well as encephalitis and even meningoencephalitis.

If a patient has a nervous form of listeriosis, this threatens him with the development of hydrocephalus, as well as dementia, and the septic form may result in the development of an infectious-toxic shock for the patient. In this case, the patient's condition will be very serious, due to the action of toxins on the body, it may even end in a coma.