Erysipelothrix/Listeria Flashcards
What is Erysipelothrix?
-
E. rhusiopathiae: Pathogenic
- Swine: Erysipelas
- Sheep & Cattle: Polyarthritis
- Chicken and Turkeys: Skin infections
- Humans: Skin infections, Erysipeloid; zoonotic pathogen
- E. tonsillarum: Nonpathogenic
What is Erysipelothrix rhusiopathiae?
- Gram positive - May appear Gram negative
- Nonspore forming
- Facultatively anaerobic slender rods
- Alpha hemolysis
- H2S production along stab line of TSI Agar
What is the habitat of E. rhusiopathiae?
- Prmary reservoir is swine
- Present in sewage or ground contaminated with feces
- Common on fish skin
- Does not survive too long in the environment
What are the antigenic characteristics of E. rhusiopathiae?
- Peptidoglycan: Heat stable
- 26 serovars
- Serovars 1 & 2
What is the mode of infection of E. rhusiopathiae?
- Ingestion
- Skin: scratches and wounds
What are the Virulence factors of E. rhusiopathiae?
- Capsule: Acidic polysaccharide
- Surface proteins: Adhesins
- Hyaluronidase: Spreading factor
- Neuraminidase
- Type III hypersensitivity: Arthritis
What is Neuraminidase?
- Cleaves sialic aci on the cell surface, which leads to vascular damage and thrombus formation
- Responsible for skin lesions
- Amount of enzyme produced correlates with virulence
What is Erysipelas?
- Pigs between 3 months to 3 years are most susceptble
- 3 Forms:
- Acute, Subacute and Chronic
- Acute: Septicemic
- Sudden onset, high fever, rapid course, high mortality
- Subacute: Milder
- Skin lesions: Diamond shaped
What do the skin lesions of Erysipeals look like?
- Appear on days 2 - 3
- Disappear on days 4 - 7
- Intensity of the lesions:
- Light pink to purplish lesions - recover
- Dark purplish to red - Death
What is the chronic form of Erysipelas result in?
- Polyarthritis
- Resembles rheumatoid arthritis in humans
- Endocarditis
- Valvular lesions resulting from bacterial emboli
Does Erysipelas affect other animals?
- Sheep & Cattle - Polyarthritis
- Turkeys
- Males more often than females
- skin injuries
- Hemorrhagic lesions
How is Erysipelas diagnosed?
- Clinical signs:
- Fever, arthritis, and skin lesions
- Bacteriologicl examination
- Recovery within 24 - 36 hours with penicillin
How is Erysipelas treated and prevented?
- Penicillin, Tetracyclines, Lincosamides, and Tylosines
- Bacterin or modified live vaccine
- Vaccinated breeding stock to transfer protection to piglets
What is Erysipeloid?
- Erysipelas in Humans
- 3 forms:
- Localized Cutaneous
- Generalized Cutaneous
- Septicemic
- Occupational disease - “Fish Handler’s Disease”
What is Listeria?
- 8 species:
- L. monocytogenes
- L. ivanovii
- Disease is called “Listeriosis”
What is Listeriosis?
- Primarily a disease of cattle, sheep, and goats
- CNS infection, Septicemia, abortion, and mastitis
- Food borne infection that causes high mortality
What is Listeria monocytogenes?
- Gram positive rods
- Nonspore forming
- Motile - umbrella motility
- Hemolytic
- Positive CAMP reaction
- More pathogenic
- CNS infection
- Disease in animals and humans
- Food borne pathogen
- Psychrophilic - can grow in the refrigerator
What is Listeria ivanovii?
- Less pathogenic
- No CNS infection
- Disease only in cattle
What are the antigenic characteristics of Listeria?
- 13 serotypes
- Serotypes:
- 4b, 1/2a, 1/2b, 3 - Animals
- 4b, 1/2a, 1/2b, 1/2c - Humans (95%)
- Somatic (peptidoglycan) and Flagellar antigens
What is the habitat of Listeria?
- Widely distributed
- Feces
- Tissues - Tonsils and lymph nodes
- Soil, Water, and vegetation
- Hardy and persistent
What is the mode of infection of Listeria?
- Ingestion
- Silage (pH > 5.0) is the most common source in dairy cattle
- Inhallation or through broken skin is possible (soil)
- Direct entry into the conjunctiva
What are the virulence factors of Listeria?
- Facultative intracellular pathogen
-
Internalin:
- Membrane associated protein is responsible for internalization
-
Listeriolysin (LLO)
- Hemolysin
-
Phospholipase C
- Allows escape from the phagosome
-
Act A
- Polymerization of actin molecules
What is Listeriosis in Ruminants?
- Infrequent but a serious disease
- Four Forms:
- CNS infection
- Abortion
- Septicemia or visceral
- Mastitis
- Rarely, Gastroenteritis, Keratoconjunctivitis
What is the CNS Form of Listeriosis in Ruminants?
- Incubation period: 3 - 4 weeks
- Meningoencephalitis (adult)
- Meningitis (preruminant calves)
- Circuling disease
- Common in winter or early spring (silage)
What is the pathogenesis of CNS Listeriosis in Ruminants?
- Poorly understood
- No septicemia
- Bacteria travel through nerves
- Trigeminal nerve from the oral cavity
What are the Clinical Signs of the CNS Form of Listeriosis in Ruminants?
- Depression
- Drooping ears
- animal holds the head to one side (torticollis)
- Protrusion of the tongue
- Salivation
- paralysis of the facia muscls
- strabismus (cross eyed)
- “Circling disease”
- Progresses to complete paralysis
- Death in 2 - 3 days
What are the CNS lesions of Listeriosis in Goats?
- No gross lesions
- May be:
- Congested meninges
- Cloudy CSF
- Discolored brain stem
- PMN and mononuclear cell infiltration
- Perivascula cuffing
What is the Abortion form of Listeriosis?
- Late in gestation
- Sporadc in cows
- Outbreaks more common in sheep and goats
- Placentitis
- No other signs
What is the Septicemic or Visceral Form of Listeriosis?
- More common in the young ruminant and in monogastrics (any age)
- Clinical Signs:
- Depression
- Dyspnea
- Salivation
- Nasal discharge
- Lacrimation
- Lesions
- Focal necrosis of Liver, Spleen, and Lymph nodes
What is Mastitis?
- Source: Feces
- Subclinical to clinical
- Suppurative infection
- Listeria in milk
What are the other forms of Listeriosis?
- Gastroenteritis with diarrhea
- sometimes with blood
- Keratconjunctivitis - Direct entry
What is Listeriosis in Monogastrics?
- Rare in Horses, pigs, dogs, and cats
- Septicemic form with or without encephalitis the most common
- Horses: Keratitis or enteritis
- Chickens: Encephalitis
What is Listeriosis in Humans?
- Zoonotic pathogen - rarely by direct contact
- Food borne pathogen:
- Milk (unpasteurized)
- Milk products
- Cold meat cuts
- Contaminations happens more often in food processing and food preparing facilities (hardy organism)
- 2,500 cases a year
- 500 deaths per year
- Causes abortion in pregnant women
- Meningitis in immune compromised adults
How is Listeriosis diagnosed?
- History: silage feeding
- Clinical Signs: neurological
- Lesions: Perivascular cuffing
-
Cultural examination: Brain, blood, milk, placenta, and fetus
- Enrichment is needed to isolate from brain
- PCR and immunohistochemistry are preferred method of diagnosis
What is the treatment for Listeriosis?
- Cattle and sheep are NOT treated
- Cost of therapy
- Could become sublinical
-
Penicillin is the drug of choice
- Tetracyclines
- Macrolides
-
Vaccine: None in the US
- Live attenuated - used in Europe and Australia
How is Listeriosis Controlled?
- Not feeding spoiled silage
- Isolation of sick animals
- Quick disposal of dead animals
- Disposal of dead animals
- Thorough cleaning of the barn after an outbreak
What is Listeria ivanovii?
- Gram Positive rods
- Non spore forming
- Also hymolytic
- Causes abortion in sheep
- Rarely causes human infection
What are the top 5 pathogens causing Food Borne Illnesses?
- Noro virus
- Salmonella
- Clostridium perfringens
- Campylobacter sp.
- Staphylococcus aureus
What are the top 5 pathogens causing food borne illnesses resulting in hospitalization?
- salmonella
- Noro Virus
- Campylobacter sp
- Toxoplsma gondii
- E. coli O157
What are the top 5 pathogens causing food borne illnesses resulting in death?
- Salmonella
- TOxoplasa gondii
- Listeria monocytogenes
- Noro virus
- Camplylobacter
