ListeriosisListeriosisListeria MonocytogenesListeria Monocytogenes

(A Psychrophilic Bacterium)(A Psychrophilic Bacterium)

What is What is ListeriosisListeriosis??

ListeriosisListeriosis is a serious infection caused by is a serious infection caused by eating foods contaminated with the eating foods contaminated with the bacterium bacterium Listeria MonocytogenesListeria Monocytogenes..

This disease affects primarily pregnant This disease affects primarily pregnant women, newborn, and adults with weakened women, newborn, and adults with weakened immune systems.immune systems.

This bacterium is too small to be seen This bacterium is too small to be seen without a microscope.without a microscope.

Listeria monocytogenes is a rod-shaped aerobic and gram positive pathogenic bacterium that invades the cytoplasm of living cells. It develops a distinctive rocket tail structure to help push through the cytoplasm.  Eventually, these "rockets" push bacteria into neighboring cells, propagating the infection

SymptomsSymptoms

FeverFever Muscle acheMuscle ache GI Sx: Nausea, diarrheaGI Sx: Nausea, diarrhea Pregnant women: mild Pregnant women: mild

flu-like Sx, miscarriage, flu-like Sx, miscarriage, still birth, premature still birth, premature delivery, or infected delivery, or infected newborn.newborn.

LethargyLethargy irritabilityirritability

If infection spreads to the If infection spreads to the nervous system: headache, nervous system: headache, stiff neck, confusion, loss stiff neck, confusion, loss of balance, or convulsions.of balance, or convulsions.

Listeria can cause Listeria can cause Pneumonia, Meningitis, Pneumonia, Meningitis, and Sepsis.and Sepsis.

ContaminationContamination Listeria MonocytogenesListeria Monocytogenes is is

found in soil and water.found in soil and water. Vegetables can become Vegetables can become

contaminated from the soil contaminated from the soil or from manure used as or from manure used as fertilizer.fertilizer.

Animals can carry the Animals can carry the bacterium without bacterium without appearing ill and can appearing ill and can contaminate foods of contaminate foods of animal origin such as animal origin such as meats and dairy products.meats and dairy products.

The bacterium has been The bacterium has been found in uncooked meats found in uncooked meats and vegetables, soft and vegetables, soft cheeses, deli cold-cuts, and cheeses, deli cold-cuts, and unpasteurized milk or unpasteurized milk or foods.foods.

If acquired at birth, the If acquired at birth, the incubation period is 7 to incubation period is 7 to 28 days.28 days.

The average incubation The average incubation period is 31 days; with a period is 31 days; with a range from 11 to 47 days.range from 11 to 47 days.

How do you get How do you get ListeriosisListeriosis??

Eating food Eating food contaminated with contaminated with Listeria.Listeria.

Babies can be born Babies can be born with with Listeriosis Listeriosis if the if the mother eats mother eats contaminated food contaminated food during pregnancy.during pregnancy.

ListeriosisListeriosis is generally is generally not contagious from not contagious from person to person.person to person.

DiagnosisDiagnosis

There is no routine screening test for There is no routine screening test for susceptibility.susceptibility.

If you have Sx of fever, or stiff neck, consult If you have Sx of fever, or stiff neck, consult your doctor.your doctor.

A blood or spinal fluid test (to cultivate the A blood or spinal fluid test (to cultivate the bacteria) will show if you have bacteria) will show if you have ListeriosisListeriosis..

During pregnancy, a blood test is the most During pregnancy, a blood test is the most reliable way to find out if your Sx are due to reliable way to find out if your Sx are due to ListeriosisListeriosis..

PreventionPrevention• Thoroughly cook raw food Thoroughly cook raw food

from animal sources.from animal sources.• Was raw vegetables Was raw vegetables

thoroughly before eating.thoroughly before eating.• Separate uncooked meats Separate uncooked meats

from vegetables, cooked foods from vegetables, cooked foods and ready-to-eat foods.and ready-to-eat foods.

• Avoid unpasteurized milk or Avoid unpasteurized milk or food.food.

• Wash hands, knives, and Wash hands, knives, and cutting boards with hot soapy cutting boards with hot soapy water for at least 20 sec after water for at least 20 sec after handling uncooked foodshandling uncooked foods..

• Observe all expiration Observe all expiration dates on food items. dates on food items.

• Consume perishable and Consume perishable and ready-to-eat foods as soon as ready-to-eat foods as soon as possible.possible.

• Do not eat soft cheeses: feta, Do not eat soft cheeses: feta, brier, camembert, blue-brier, camembert, blue-veined, or Mexican-style etc.veined, or Mexican-style etc.

• Do not east refrigerated meat Do not east refrigerated meat spreads, smoked salmon, spreads, smoked salmon, smoked seafood; canned or smoked seafood; canned or shelf-stable smoked seafood shelf-stable smoked seafood may be eaten.may be eaten.

• Listeria monocytogenesListeria monocytogenes is is killed by cooking or by killed by cooking or by heating methods, including heating methods, including pasteurization.pasteurization.

TreatmentTreatment ListeriosisListeriosis is a serious disease requiring hospitilization. is a serious disease requiring hospitilization. A combination of antibiotics is given intravenously through A combination of antibiotics is given intravenously through

a small straw-like catheter.a small straw-like catheter. When infection occurs during pregnancy, antibiotics must When infection occurs during pregnancy, antibiotics must

be given promptly to the mother to prevent infection of the be given promptly to the mother to prevent infection of the fetus or newborn.fetus or newborn.

Babies with Babies with ListeriosisListeriosis receive the same antibiotics as receive the same antibiotics as adults.adults.

The duration of antibiotic treatment is at least 2 weeks.The duration of antibiotic treatment is at least 2 weeks. Even with prompt treatment, some infections result in Even with prompt treatment, some infections result in

death.death.

StatisticsStatistics

About 2,500 people in the U.S develop About 2,500 people in the U.S develop ListeriosisListeriosis each year. each year. 5 out of every 100 people carry 5 out of every 100 people carry Listeria MonocytogenesListeria Monocytogenes in their in their

intestines.intestines. About 20% of people die from the infection.About 20% of people die from the infection. In 1989, there were 1,965 cases of Listeriosis with 481 deaths.In 1989, there were 1,965 cases of Listeriosis with 481 deaths. In 1993, there were 1,092 cases of Listeriosis with 248 deaths.In 1993, there were 1,092 cases of Listeriosis with 248 deaths. Listeria MonocytogenesListeria Monocytogenes reached the blood and cerebrospinal fluid in reached the blood and cerebrospinal fluid in

89% of cases.89% of cases. Listeriosis Listeriosis results is a higher number of hospitalizations than any other results is a higher number of hospitalizations than any other

food-born illness.food-born illness. Pregnant women account for 27% of cases, people with Pregnant women account for 27% of cases, people with

immunodeficiency disorders account for 70% of cases.immunodeficiency disorders account for 70% of cases. AIDS patients are 280 time more likely to contract AIDS patients are 280 time more likely to contract ListeriosisListeriosis than than

others.others.

Government InterventionGovernment Intervention

FDA( Food and Drug Administration) and (FSIS) U.S FDA( Food and Drug Administration) and (FSIS) U.S Department of Agriculture monitor food regularly.Department of Agriculture monitor food regularly.

FSIS now requires plants that slaughter and process meat FSIS now requires plants that slaughter and process meat and poultry to use a process called (HACCP) Pathogen and poultry to use a process called (HACCP) Pathogen Reduction and Hazard Analysis and Control PointReduction and Hazard Analysis and Control Point

When a processed food is found to be contaminated, food When a processed food is found to be contaminated, food monitoring and plant inspection are intensified, and if monitoring and plant inspection are intensified, and if necessary, the implicated food is recalled.necessary, the implicated food is recalled.

NCID( National Center for Infectious Disease is extensively NCID( National Center for Infectious Disease is extensively studying studying ListeriosisListeriosis to help measure the impact of prevention to help measure the impact of prevention activities. activities.

Early detection and reporting of outbreaks can help identify Early detection and reporting of outbreaks can help identify sources of infection and prevent more cases of the disease.sources of infection and prevent more cases of the disease.

The EndThe End