Listeriosis Listeria monocytogenes

Facts ~ 2,500 (1,100) seriously ill per year 500 (415) die per year Soil and water Gram-positive rod-shaped bacterium Parasitic Less common Highest hospitalization rate

Hardy Non-spore forming Grow 3°C (37.5 °F) Resist –Freezing –Drying –Heat

Identification Human –Blood –Cerebrospinal fluid Food –24-48 hours –5-7 days

Reservoir 1-10% of humans may be intestinal carrier 37 mammalian species 17 species of birds Fish and shellfish

Onset >1000 organisms Gastrointestinal –< 12 hours Phagocytic –Brain –transplacental migration Nervous –Few days - 3 weeks

Influenza-like Symptoms Gastrointestinal –Fever –Nausea –Diarrhea –Vomiting –Muscle aches Nervous –Headache –Stiff neck –Confusion –Loss of balance –Convulsions Duration 5-10 days

Target Populations Pregnant women/fetus Immunocompromised Cancer patients - leukemic Elderly Normal people

Contamination Vegetables –Soil or fertilizer Meats –Ill animals –Raw milk –Before packaging (hot dogs)* Soft Cheeses* (brie, feta, queso)

Prevention Proper cooking Temperatures Wash vegetables Proper storage Avoid unpasteurized (raw) milk Proper handwashing Sanitizer buckets for utensils and clothes

Outbreak California (1985) –Mexican-style cheese (milk) –86 cases (58) –47 deaths –Stillbirths –Pinholes in pasteurizing unit Ohio (2000) –2 cases

Recalls John Morrell & Co. (2002) –140,000 pounds of hot dogs Bosell Foods, Inc (1999) –350 pounds of sliced ham