What are the symptoms of listeria poisoning

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

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Causes, Symptoms, Treatment & Prevention

Overview

What is listeriosis?

Listeriosis is a foodborne illness. The germ Listeria monocytogenes causes listeriosis. Listeria monocytogenes is commonly found in nature, especially in soil, groundwater, rotting vegetation and animal feces (poop).

Most people get listeriosis from eating contaminated foods. The listeriosis incubation period (the time when you first get infected and when you first show symptoms) varies. It usually takes one to two weeks, but it can be as short as a couple of days or as long as three months.

Other names for listeriosis include L. monocytogenes and listeria.

In what foods is listeria found?

Contaminated foods are the most common cause of listeriosis infections. The most common foods that cause listeriosis include:

Hot dogs.
Deli meats.
Fresh vegetables.
Fresh fruits, especially melons.
Unpasteurized dairy products (sterilized to kill bacteria).

These foods have the highest risk of L. monocytogenes contamination. However, listeriosis can affect almost any improperly handled or prepared food.

The bacteria L. monocytogenes is unique from many other foodborne illnesses. It survives and even multiplies in low temperatures, including refrigerators and freezers. The bacteria can multiply to dangerous levels during storage.

Food that has spoiled breaks down and develops an unpleasant smell, taste or change in texture. When L. monocytogenes bacteria contaminate food, the smell, taste and texture don’t change.

Who does listeriosis affect?

Anyone can get listeriosis. However, it isn’t as dangerous for those with a healthy immune system. Those who are at the greatest risk of becoming very ill or dying include:

Pregnant people.
Developing fetuses.
People 65 or older.
People with a weakened immune system, usually from another condition (like AIDS or cancer) or taking prescribed immunosuppressive medications.

How common is listeria?

About 1,600 people get listeria in the United States each year.

Symptoms and Causes

Flu-like symptoms are common signs of listeriosis.

What are the symptoms of listeriosis?

Listeriosis symptoms include:

Fever.
Chills.
Headache.
Upset stomach.
Diarrhea.
Nausea and vomiting.
Muscle aches.
Confusion.
Loss of balance.
Convulsions (muscle contractions that you can’t control).

A severe listeriosis infection may spread to your bloodstream or brain. Severe infections may cause sepsis, meningitis or encephalitis.

What are the symptoms of listeriosis in pregnant people?

The most common symptoms of listeriosis in pregnant people are usually fever and other flu-like symptoms, especially fatigue and muscle aches.

Listeriosis may quickly cause miscarriage, stillbirth, premature birth and death in newborn babies without timely treatment.

What are the symptoms of listeriosis in newborn babies?

Listeriosis symptoms in newborn babies include:

Fever.
Vomiting.
Constant crying.
Trouble breathing (rapid breathing, short breaths and wheezing).
No interest in eating.

How do you get listeriosis?

Most people contract listeriosis from contaminated food.

Pregnant people can transmit the L. monocytogenes bacteria to the fetus through the placenta. They can also transmit the bacteria to their babies in the birth canal.

Is listeriosis contagious?

You can’t pass listeriosis to another person unless a pregnant person passes it to the fetus.

Diagnosis and Tests

How do you know if you have listeriosis?

Your healthcare provider can diagnose listeriosis after evaluating your symptoms and conducting medical tests. Tests may include checking the following for the presence of L. monocytogenes:

Blood.
Cerebrospinal fluid (a clear fluid in your brain and spinal cord).
Meconium (your baby’s first poop; it’s dark green and thicker and stickier than normal poop).
Vomit.
Food.
Animal feed.

Your healthcare provider may order bacterial culture tests on your blood or placenta if you’re pregnant.

Management and Treatment

Can listeriosis be cured?

Yes, there is a cure for listeriosis. Your healthcare provider can prescribe antibiotics to rid your body of the infection.

Your healthcare provider is more likely to prescribe antibiotics to babies or if you’re pregnant, 65 or older or have a weakened immune system. Antibiotics commonly used to treat listeriosis include sulfamethoxazole (Bacter-Aid DS®) and ampicillin (Principen®).

Your provider may also prescribe medication to manage specific symptoms, including nausea and vomiting.

If you have mild symptoms, you may not need treatment.

If your baby is born with a listeriosis infection, your healthcare provider will give them antibiotics shortly after birth.

What are the side effects of antibiotics?

Side effects of antibiotics may include:

Allergic reactions. Allergic reactions may range from mild rashes and itching to skin blisters, swelling in your face and throat and difficulty breathing. Talk to your healthcare provider about any past drug reactions or allergies.
Clostridioides difficile. Clostridioides difficile (C. difficile or C. diff) is a bacteria that causes diarrhea.
Antibiotic resistance. Antibiotic resistance occurs when bacteria change and get stronger so that antibiotic medicines can’t kill them or stop their growth. Bacterial infections then become difficult to treat with medications.

How do I manage my symptoms?

If you have listeriosis, the best way to manage your symptoms is to:

Take prescription medications as directed by your healthcare provider.
Rest.
Drink lots of fluids.
Eat a light diet.
Take nonsteroidal anti-inflammatory drugs (NSAIDs) to manage fever and relieve muscle aches.

Not everyone can take NSAIDs. It’s a good idea to check with your healthcare provider before use.

How soon after treatment will I feel better?

Most people with a healthy immune system will feel better after a few days without treatment.

If you have a severe listeriosis infection, you should start to feel better three to five days after you start taking antibiotics.

It’s important to take your full course of antibiotics as prescribed by your healthcare provider, even if you start to feel better. If you don’t finish your full course of antibiotics, your listeriosis may come back and be more challenging to treat.

Prevention

How can I reduce my risk of contracting

listeria?

If you have a weak immune system or are pregnant, it’s a good idea to take precautions with what you eat and drink and how you store and prepare food.

Check product labels to ensure that any dairy products or juices are pasteurized. Avoid unpasteurized dairy products and juices.
Wash your hands and any food surfaces before and after cooking.
Use a scrub brush, clean running water and a fruit and vegetable wash to clean raw fruits and vegetables.
Cook hot dogs, egg dishes, seafood and deli meats to an internal temperature of 165 degrees F (74 degrees C). If you can’t, you should avoid them.
Don’t eat refrigerated pâté (pureed meat) or meat spreads from a deli or the meat counter at a grocery store. Foods that don’t require refrigeration, like canned or shelf-stable pâté and meat spreads, are safe to eat. Refrigerate these items after opening.
Heat your leftovers until they are steaming hot. Don’t eat any leftovers if they are several days old.
Wrap food in plastic wrap or foil, or place it in plastic bags or clean, covered containers before you place them in your refrigerator. Ensure that foods such as raw meat don’t leak juices onto other foods.
Clean up any spills in your refrigerator right away, especially meat juices.

Outlook / Prognosis

What can I expect if I have listeriosis?

If you have a healthy immune system and develop listeriosis, you’ll usually feel better without treatment in about two days.

If you have a weakened immune system, are pregnant or have a baby, listeriosis may cause serious illness or death. Contact your healthcare provider right away. With a quick diagnosis and proper treatment, your stand a better chance of a full recovery.

Living With

When should I see my healthcare provider?

Call your healthcare provider if:

You’re pregnant, over 65 or have a weakened immune system and display listeriosis symptoms.
The U.S. Food and Drug Administration (FDA) has recalled a food or drink that you’ve recently consumed because of a listeriosis outbreak.
You have a baby who displays listeriosis symptoms.
Your symptoms don’t go away a few days after starting antibiotics.

What questions should I ask my healthcare provider?

How do you know that I have listeriosis?
If I don’t have listeriosis, what other condition might I have?
How did I get listeriosis?
Do I need antibiotics or any other medications?
For how long and at what times of the day should I take my medications?
How should I store my medications?
Is my fetus at risk of having listeriosis?
How can I protect my fetus?
How do you know that my newborn baby has listeriosis?
What medications will you prescribe my newborn baby?
Will my newborn baby have any long-term effects from listeriosis?

A note from Cleveland Clinic

Listeriosis is a relatively rare bacterial infection. It may have serious effects on pregnant people, fetuses, newborn babies, people 65 or older and people who have weakened immune symptoms. You’ll likely feel better after a few days without treatment if you have a healthy immune system. Talk to your healthcare provider right away if you notice any symptoms of listeriosis. Because listeriosis has an incubation period that may last up to a few months, it’s also a good idea to talk to your healthcare provider if you’ve consumed any recalled foods or drinks.

To help prevent a listeriosis infection, wash your hands, cook meats to a safe temperature and clean fruits and vegetables.

Listeria as a causative agent of food poisoning

For many centuries, mankind has known that eating poor-quality products can provoke human poisoning. When microorganisms enter food, toxins accumulate in the latter, which can cause food poisoning.

They are characterized by sudden onset, bouts of nausea and repeated vomiting, diarrhoea, cramping abdominal pain, fever and symptoms of intoxication. nine0003

Foodborne infections can be caused by various microorganisms, including Listeria. There are several types of Listeria, but only Listeria monocytogenes causes food poisoning in humans. Listeriosis is a foodborne infection caused by a specific bacterial species, Listeria monocytogenes.

Where does listeriosis come from? Who is at risk for this disease? And how to prevent it? Galina Vyacheslavovna Safroshina, head of the sector of food microbiology and veterinary and sanitary examination of the testing laboratory of the FGBU "Bryansk MVL", will give us answers to these questions. nine0003

— Galina Vyacheslavovna, how does listeriosis occur?

- Listeria monocytogenes is actually everywhere. They can be found in soil, dirty water, the gastrointestinal tract, and animal feces.

Listeria has a peculiarity: unlike many other pathogens, they thrive at low temperatures. Therefore, they actively multiply, for example, in refrigerators. Listeria has another insidious property: the ability to multiply in salty foods of plant and animal origin. If most microbes die under these conditions, then Listeria can withstand a concentration of table salt up to 6-20%. nine0003

Listeria die at boiling temperature, and under the influence of sunlight, the causative agent of the disease will live no more than 15 days.

The risk of catching listeriosis increases if you consume:

• raw vegetables and fruits that have not been washed well;

• uncooked meat;

• raw foods that have been stored in the refrigerator for a long time;

• unpasteurized milk;

• Prepared foods such as soft cheese, hot dogs, deli meats, salads that have been contaminated with Listeria (eg from someone else's dirty hands). nine0003

— Who is at risk for listeriosis?

— Most often, pregnant women, newborn children, elderly people over 65 years of age, that is, those who have a weakened immune system, face severe complications of the course of listeriosis.

— Galina Vyacheslavovna, is it possible to prevent listeriosis, if so, how?

- Listeriosis can be prevented in the same way as other foodborne infections, namely by following the rules of prevention:

• Wash your hands regularly with warm water and soap. Especially before meals, as well as before and after cooking. nine0003

• If you have cut or otherwise cooked raw foods, wash anything that has come into contact with them in hot water and detergent: cutting boards, knives, plates.

• Wash raw vegetables and fruits thoroughly before eating. It is best to do this with a brush under running water.

• Fry meat, poultry, and bring eggs to full readiness. Listeria die when cooked. If you are at risk, take extra precautions. In particular, avoid unpasteurized milk, soft cheeses, and convenience foods (hot dogs, cold cuts) unless they are heated to steam. nine0003

In Russia, the incidence of listeriosis in recent years has been at the level of single cases (less than 0.05 per 100,000 population), which is 15 times lower than similar indicators in European countries. But doctors take it very seriously. The fact is that in some people the infection spreads to the central nervous system and can provoke a serious complication - bacterial meningitis. Every fifth person who becomes infected in this case dies.

Specialists of the sector of food microbiology and veterinary and sanitary examination of the testing center of the Federal State Budgetary Institution "Bryansk MVL" conduct tests of food products for the "Listeria monocytogenes" indicator in accordance with the scope of accreditation, using the microbiological method of research. The use of modern measuring instruments and equipment, as well as the introduction of new research methods, make it possible to ensure a high level of reliability of tests carried out on the basis of the institution. Laboratory tests are carried out by qualified specialists of the Federal State Budgetary Institution "Bryansk MVL", who regularly improve their professional skills and qualifications. nine0003

Tags: bryansk mvl, veterinary medicine, veterinary laboratory, research, listeria, listeriosis, mvl, rosselkhoznadzor, toxic infections are deli meats and cheeses purchased from deli departments in several states.

It is difficult for investigating experts to identify one food as the source of outbreaks associated with deli meats and cheeses. This is due to the fact that Listeria spreads easily between foods and in the gastronomic environment and can be found for long periods inside deli displays and on equipment. Germ-contaminated food likely led to the spread of Listeria strain , , which caused this , grocery store outbreak in several states. Investigators are working to identify specific foods or delicacies that may be contaminated with the strain that caused the outbreak. nine0003

November 09, 2022

US Centers for Disease Control and Prevention (CDC), multi-state health and regulatory officials, USDA-FSIS, and Food Safety Inspection Service The US Food and Drug Administration (FDA) is collecting various types of data to investigate the listeriosis outbreak in several states.

Interviews with patients and laboratory results indicate that contaminated listeria meats and cheeses from deli departments are the cause of the disease. Investigators are still working to identify specific foods or delicacies that may be contaminated with the strain that caused the outbreak.

Epidemiological data

As of November 09, 2022, there were 16 people in 6 states infected with the outbreak strain of Listeria (see map). Samples from sick people were collected from April 17, 2021 to 29September 2022 (see chart). The true number of sick people in this outbreak is likely higher than reported, and the outbreak may not be limited to states where the disease is known. This is because some people recover without medical attention and are not tested for Listeria . Also, recent cases may not have been reported yet, as it usually takes 3-4 weeks to determine if a person has become ill as a result of an outbreak.

Public health officials collect information on the age, ethnicity, and other demographics of people who are sick, as well as the types of food they have eaten, to provide supporting information that can help determine the source of an outbreak. The age of patients varies from 38 to 92 years, the average age is 74 years, 62% are men. Of the 13 people for whom ethnicity information is available, 11 are of Eastern European origin or speak Russian. Of the 14 people known, 13 were hospitalized, of which one person (a resident of Maryland) died. One case concerns an illness during pregnancy that led to the termination of the pregnancy. nine0003

State and local health authorities ask people about the foods they ate in the month before they got sick. Of the 12 people interviewed, 11 reported that they ate meat or cheese from deli departments. Among the seven patients in New York City, five bought cut deli meats or cheese from at least one NetCost Market grocery store, which sells products from different countries. Out-of-state patients bought deli meats or cheeses from other grocery stores. nine0003

Investigators do not believe that NetCost Market grocery stores are the only source of illness, as some people who fell ill during the outbreak did not shop at NetCost Market. Microbially contaminated food likely led to an outbreak of Listeria strain in grocery stores in several states.

Laboratory data

Public health researchers use PulseNet to identify cases that may be related to this outbreak. CDC PulseNet maintains a national DNA fingerprint database of bacteria that cause foodborne illness. DNA fingerprinting is performed on bacteria using a technique called whole genome sequencing (WGS). nine0003

WGS results indicated that bacteria from samples of sick people are genetically closely related. This suggests that the disease in people during this outbreak developed as a result of eating the same food.

In 2021, New York State and New York City public health officials detected the outbreak-causing Listeria strain in several environmental and food samples: