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Larry M. Bush
, MD, FACP, Charles E. Schmidt College of Medicine, Florida Atlantic University;
Maria T. Vazquez-Pertejo
, MD, FACP, Wellington Regional Medical Center
Revised/Revised March 2023
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- symptoms and signs
- key points
Listeriosis is bacteremia, meningitis, cerebritis, dermatitis, oculoglandular syndrome, intrauterine and neonatal infections, or rarely endocarditis caused byListeriaspecies. Symptoms vary according to the organ system affected. Intrauterine infection can cause fetal death. Diagnosis is by laboratory isolation. Treatment includes penicillin orampicillin(often with aminoglycosides) ortrimetoprim/sulfametoxazol.
(See tooListeriosis Neonatal Listeriosis .)
Listeriathey are small, non-acidfast, non-capsulated, non-sporulated, beta-hemolytic, aerobic and facultatively anaerobic gram-positive bacilli that exhibit characteristic rotational motility. They are present worldwide in the environment and in the gut of humans, non-human mammals, birds and crustaceans. There are several species ofListeria, butL. monocytogenesis the main pathogen in humans.
In the US, there are about 1,600 cases of listeriosis annually and about 260 people die (1 General reference Listeriosis is bacteremia, meningitis, cerebritis, dermatitis, oculoglandular syndrome, intrauterine and neonatal infections, or rarely endocarditis caused by Listeria species. Symptoms... read more ). The peak is in summer. Attack rates are highest in newborns, adults aged ≥ 60 years, and immunocompromised patients, including patients with HIV/AIDS. Listeriosis is 10 times more likely in pregnant women and 24 times more likely in pregnant Hispanic women than the general population (1 General reference Listeriosis is bacteremia, meningitis, cerebritis, dermatitis, oculoglandular syndrome, intrauterine and neonatal infections, or rarely endocarditis caused by Listeria species. Symptoms... read more ).
WhyL. monocytogenesis ubiquitous in the environment, opportunities for contamination are numerous during the food production process. Almost all types of food can harbor and transmitL. monocytogenes, but infection usually occurs by eating contaminated dairy products, raw vegetables, meats or, especially, refrigerated foods that do not require cooking before consumption. Contamination is favored by the ability toL. monocytogenesto survive and grow in refrigerator temperatures.
Infection can also occur through direct contact with and during the slaughter of infected animals.
Pearls and Traps
Listeria monocytogenescan reproduce at refrigerated temperatures, so lightly contaminated refrigerated foods can become heavily contaminated.
WhyL. monocytogenesmultiplies intracellularly, control of listeriosis requires cell-mediated immunity; thus, the following people are at high risk:
In pregnant women, listerial infection is usually mild. However, the infection can spread before and during childbirth from mother to child and can cause miscarriage, stillbirth, premature delivery, or early infant death.
Listeriacan cause life-threatening infection in the newborn (seeListeriosis Neonatal Listeriosis ), Includingbacteremia Neonatal Listeriosis Neonatal listeriosis is acquired transplacentally or during or after delivery. The symptoms are those of sepsis. Diagnosis is made by culture or polymerase chain reaction testing of the mother and baby... read more epneumonia Neonatal Pneumonia Neonatal pneumonia is a lung infection in a newborn baby. Onset may occur hours after birth and be part of a generalized sepsis syndrome, or after 7 days and confined to the lungs. Signals can be limited... read more , and are a common cause ofneonatal bacterial meningitis Neonatal bacterial meningitis Neonatal bacterial meningitis is inflammation of the meninges due to bacterial invasion. Signs are sepsis, central nervous system irritation (eg lethargy, seizures, vomiting, irritability... read more .
1.CDC: People at Risk—Pregnant Women and Newborns. Accessed on 12/22/2022.
Symptoms and Signs of Listeriosis
primary listerial bacteremiait is rare and causes high fever without localized symptoms and signs. Endocarditis, peritonitis, osteomyelitis, septic arthritis, cholecystitis, and pleuropneumonia may occur. Febrile gastroenteritis may occur after ingestion of contaminated food. Listerial bacteremia during pregnancy can lead to intrauterine infection, chorioamnionitis, preterm labor, stillbirth, or neonatal infections.
Meningitisis due toListeriain up to 20% of cases in neonates and in patients>60 years old. Twenty percent of cases progress to cerebritis, diffuse encephalitis, or, rarely, rhombenencephalitis and abscesses; rhomboencephalitis manifests as altered consciousness, cranial nerve palsies, cerebellar signs, and motor or sensory loss.
Listeriosis oculoglandularmay cause ophthalmitis and regional lymph node enlargement (Parinaud's syndrome). It may follow conjunctival inoculation and, if untreated, may progress to bacteremia and meningitis.
Diagnosis of Listeria
Listerial infections are diagnosed by culture of blood or cerebrospinal fluid. The laboratory must be informed whenL. monocytogenessuspected because the organism is easily confused with diphtheroids.
In all listerial infections, IgG agglutinin titers peak 2 to 4 weeks after onset.
Ampicillinorpenicillin G, usually with an aminoglycoside
Listerial meningitis is best treated withampicillin2 g IV every 4 hours. Most authorities recommend addinggentamicin(1 mg/kg IV every 8 hours) based on in vitro synergy. Cephalosporins are not effective.
For the treatment of neonatal meningitis, seeOrganism-specific antibiotic therapy Organism-specific antibiotics Neonatal bacterial meningitis is inflammation of the meninges due to bacterial invasion. Signs are sepsis, central nervous system irritation (eg lethargy, seizures, vomiting, irritability... read more .
Endocarditis and primary listerial bacteremia are treated withampicillin2 g IV every 4 hours plusgentamicin(for synergy) administered for 6 weeks (for endocarditis) or 2 weeks (for bacteremia) in addition to defervescence.
Oculoglandular listeriosis and listerial dermatitis should respond toerythromycin10 mg/kg orally every 6 hours, continued until 1 week after defervescence.
Cephalosporins have no in vitro activity and should not be used; failures withvancomycinhave been reported.Trimethoprim/sulfamethoxazole 5/25 mg/kg IV every 8 hours is an alternative.Linezolidit is active in vitro, but clinical experience is lacking.
Because food contamination is common and becauseL. monocytogenescan reproduce at refrigerated temperatures, lightly contaminated foods can become heavily contaminated even during refrigeration. This problem is of particular concern when foods (eg refrigerated ready-to-eat foods) are consumed without further cooking. Thus, proper food hygiene is important, particularly for people at risk (eg, immunocompromised patients, pregnant women, the elderly). Those at risk should avoid eating the following:
Soft cheeses made with unpasteurized milk (eg, feta, brie, camembert, queso fresco, queso blanco); raw (unpasteurized) milk and dairy products, althoughListeriacontamination can occur after pasteurization
Refrigerated ready-to-eat foods (e.g., hot dogs, deli meats, pates, meat patties) unless heated to an internal temperature of 73.9°C (165°F) or until very warm before serving
Chilled smoked seafood (e.g., nova style, lox, kipper, smoked, beef jerky), unless cooked
L. monocytogenesit is very common in the environment but causes infection in only about 1,600 people annually in the US, usually through contaminated food products.
Attack rates are higher in newborns, adults≥60 years, pregnant women and immunocompromised patients.
Several organ systems can be affected; Maternal infection during pregnancy can cause fetal death.
Butampicillin, usually moregentamicin.
Advise high-risk patients to prevent illness by not eating foods that are likely to be contaminated.
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Listeriosis is an infectious disease caused by the bacterium Listeria monocytogenes.Is listeriosis reported to CDC? ›
However, CDC is concerned that illnesses continue to be reported. Listeria illness is rare, but it can result in serious illness or death. Listeria is especially harmful if you are pregnant, aged 65 or older, or have a weakened immune system.Do you have to report listeriosis? ›
In the United States, listeriosis is nationally notifiable, meaning the infections must be reported to local, state, territorial, or federal public health authorities, who monitor the disease and look for signs of an outbreak.What is the diagnostic procedure of listeriosis? ›
A blood test is often the most effective way to determine whether you have a listeria infection. In some cases, samples of urine or spinal fluid will be tested as well.Is Listeria contagious or infectious? ›
Is listeria contagious? Listeria bacteria is spread by contaminated food and water. It is not contagious from person to person, however extra caution should always be taken among those who are infected.Why is listeriosis an infectious disease? ›
Listeriosis is an infection caused by the bacteria Listeria monocytogenes. People become infected by eating foods contaminated with the bacteria. Listeria may infect many different sites in the body, such as the brain, spinal cord membranes, or the bloodstream.Does Listeria require isolation? ›
Diagnosis requires isolation of L. monocytogenes from normally sterile clinical specimens (CSF, blood, joint fluid, and so forth) and identification through standard microbiologic techniques. Food samples that are sent in should be handled by the sanitarian.Are Listeria and listeriosis the same? ›
What is listeriosis? Listeriosis is a serious infection caused by the germ Listeria monocytogenes. People usually become ill with listeriosis after eating contaminated food. The disease primarily affects pregnant women, newborns, older adults, and people with weakened immune systems.Is listeriosis A virus or bacteria? ›
Listeriosis is a serious infection usually caused by eating food contaminated with the bacterium Listeria monocytogenes.Can you sue if you get Listeria? ›
Can I Sue for Listeriosis? Yes, you can sue for listeriosis food poisoning if there is sufficient evidence to connect the illness to a food product. These cases involve a product contaminated during processing and sold at a grocery store or other retailer (Costco or Walmart, for example).
The Listeria Rule states that Lm is a hazard that establishments producing post-lethality exposed RTE meat and poultry products must control through HACCP plans, prevent in the processing environment through a Sanitation SOP, or prevent through another prerequisite program.What biohazard level is Listeria? ›
CAUTION: Listeria monocytogenes is a Biosafety Level 2 (BSL-2) pathogen.What is the first line treatment for Listeria? ›
Ampicillin is the drug of choice. It interferes with bacterial cell wall synthesis during active multiplication, causing bactericidal activity against susceptible organisms.What are listeriosis Prevention measures? ›
- Cook thoroughly raw food from animal sources, such as beef, pork, or poultry.
- Wash raw vegetables thoroughly before eating.
- Keep uncooked meats separate from vegetables and from cooked foods and ready-to-eat foods.
- Avoid raw (unpasteurized) milk or foods made from raw milk.
Most healthy patients who are exposed to listeria and develop symptoms will not require any sort of treatment. Their immune system will eradicate the bacteria, and symptoms will tend to go away within three days, though they may last as long as one week.How do you get rid of Listeria? ›
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.What are the first signs of Listeria? ›
- Muscle aches.
Intestinal illness: Most people recover from intestinal illness without antibiotic treatment. Antibiotics are needed only for patients who are very ill or at risk of becoming very ill. People who have an intestinal illness should drink extra fluids while they have diarrhea.What antibiotic kills Listeria? ›
Listeriosis is treated with antibiotics. The most commonly prescribed treatment is intravenous ampicillin. Many physicians also recommend treatment with the antibiotic gentamicin in combination with ampicillin.What antibiotics are used to treat listeriosis? ›
Ampicillin in combination with an aminoglycoside such as gentamicin is the therapy of choice. Listeria is not susceptible to cephalosporins of any generation. Therefore, cephalosporins should not be used to treat Listeria infections.
Once listeriosis is diagnosed, high-dose penicillin or ampicillin is the treatment of choice.Can a person spread Listeria? ›
The main route of transmission is oral, through ingestion of contaminated food. Other routes include mother-to-fetus transmission via the placenta or at birth. The infectious dose is unknown. Horizontal human-to-human infection has not been documented.What is the incubation period of listeriosis? ›
Cases involving a blood infection have a fairly short incubation period, with a median of 2 days. For cases involving encephalitis or meningitis, the incubation period is longer, with a median of 9 days. There is also a skin form of listeriosis that results from intact skin coming into direct contact with the bacteria.How long does Listeria bacteria live on surfaces? ›
|Type of bacterium||Duration of persistence (range)||Reference(s)|
|Listeria spp.||1 day – months||[15, 90, 102]|
|Mycobacterium bovis||> 2 months||[13, 90]|
|Mycobacterium tuberculosis||1 day – 4 months||[30, 90]|
|Neisseria gonorrhoeae||1 – 3 days||[24, 27, 90]|
If a facility has Listeria germs, the germs can spread to food that touches contaminated equipment or surfaces. Listeria can also spread from contaminated food to surfaces. It can even grow on foods kept in the refrigerator. The good news is that Listeria is easily killed by heating food to a high enough temperature.What foods carry Listeria? ›
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.
Higher-risk people other than pregnant women: Symptoms can include fever, muscle aches, headache, stiff neck, confusion, loss of balance, and convulsions. Pregnant women: Pregnant women typically experience only fever, and other non-specific symptoms like chills and headache.What temperature kills Listeria? ›
Reduce your risk for listeriosis by: Cooking raw food from animal sources, such as beef, pork or poultry to the correct temperature. 145 degrees F for whole meats, plus 3 minutes stand time for safety. 160 F for ground meats, no stand time needed.What foods should you avoid if you have Listeria? ›
Hot dogs, deli meats, and luncheon meats - unless they're reheated until steaming hot. Soft cheeses like Feta, Brie, and Camembert, "blue-veined cheeses," or "queso blanco," "queso fresco," or Panela - unless they're made with pasteurized milk. Make sure the label says, "made with pasteurized milk."
Symptoms of intestinal illness usually start within 24 hours after eating food contaminated with Listeria and usually last 1–3 days.
They are Arkansas, California, Colorado, Missouri, New York, North Carolina, Pennsylvania, South Dakota, and Washington. Listeriosis can cause a variety of symptoms, such as fever and diarrhea, similar to other foodborne pathogens.What toxin does Listeria produce? ›
Listeria monocytogenes is a foodborne pathogen capable of secreting listeriolysin O (LLO), a pore-forming toxin encoded by the hly gene.What are the 6 states of Listeria? ›
The six states that have been affected by the Listeria outbreak are California, Illinois, Maryland, New Jersey, Massachusetts, and New York. Of these states, New York had had the highest number of reported sick people.Does vinegar prevent Listeria? ›
Two other household products that can be effective against Listeria on food contact surfaces are hydrogen peroxide (available in 3% concentration) and distilled white vinegar (available in 5% concentration). Cooking foods thoroughly will destroy any Listeria that may be present on the food.What are some interesting facts about Listeria? ›
1) Listeria bacteria were first discovered in the 1920s, and a Listeriosis infection cause by the rod-shaped bacteria can take between 3 and 70 days to manifest as symptoms. 2) While formal diagnosis requires a blood test, common symptoms include headaches, fever, stiff neck, vomiting and diarrhoea lasting 2-3 days.Can Listeria cause permanent damage? ›
Listeria infections can lead to meningitis, an inflammation of the membranes surrounding the brain. If a newborn infant or fetus is infected with Listeria, long-term consequences may include mental retardation, seizures, paralysis, blindness, or deafness.Do most people recover from Listeria? ›
For most people, listeriosis is mild and gets better in a few days. You can usually look after yourself at home by resting and drinking plenty of fluids. If you're at a higher risk of getting seriously ill (for example, you're pregnant or have a weakened immune system), you may need antibiotics.How often is Listeria fatal? ›
CDC estimates that listeriosis is the third leading cause of death from foodborne illness with about 260 deaths per year. Nearly everyone with listeriosis is hospitalized. The case-fatality rate is about 20%.What type of infection is listeriosis? ›
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.What is the classification of listeriosis? ›
Listeria monocytogenes belongs to the category of facultative anaerobic bacteria, and is the pathogen of listeriosis, potentially lethal disease for humans.
The genus Listeria belongs to the class Bacilli and the order Bacillales, which also includes Bacillus and Staphylococcus.Is listeriosis a viral or bacterial infection? ›
Listeriosis is a serious infection usually caused by eating food contaminated with the bacterium Listeria monocytogenes.What antibiotics are used to treat Listeria? ›
Once listeriosis is diagnosed, high-dose penicillin or ampicillin is the treatment of choice.What are examples of listeriosis? ›
Humans are infected when they consume foods that harbor the bacteria. The most common foods to cause listeriosis outbreaks are deli meats and unpasteurized dairy products. However, many other foods have also been found to spark outbreaks, including caramel apples, cantaloupe, and cabbages fertilized by sheep manure.Who is most likely to get listeriosis? ›
Listeria is most likely to sicken pregnant women and their newborns, adults aged 65 or older, and people with weakened immune systems.What is another name for listeriosis? ›
Other names for listeriosis include L. monocytogenes and listeria.What biosafety level is Listeria? ›
Listeriosis is treated with antibiotics. The symptoms vary with the infected person: Higher-risk persons other than pregnant women: Symptoms can include fever, muscle aches, headache, stiff neck, confusion, loss of balance, and convulsions.What is the main cause of Listeria? ›
How do people get infected with Listeria? Listeriosis is usually caused by eating food contaminated with Listeria monocytogenes. If infection occurs during pregnancy, Listeria bacteria can spread through the placenta.Where is Listeria most commonly found? ›
Meats, cheeses, and salads from the deli
Products sold at the deli, especially those sliced or prepared at the deli, can be contaminated with Listeria. Listeria spreads easily among deli equipment, surfaces, hands, and food. Deli products are kept refrigerated, but refrigeration does not kill Listeria.
Listeriosis is treated with antibiotics. The symptoms vary with the infected person: Higher-risk people other than pregnant women: Symptoms can include fever, muscle aches, headache, stiff neck, confusion, loss of balance, and convulsions.How long does Listeria last in the body? ›
Symptoms of intestinal illness usually start within 24 hours after eating food contaminated with Listeria and usually last 1–3 days.Does Listeria go away on its own? ›
Listeriosis is a rare infection caused by bacteria called listeria. It usually goes away on its own, but can cause serious problems for some people.