Erysipelothrix/Listeria Flashcards
(40 cards)
1
Q
What is Erysipelothrix?
A
-
E. rhusiopathiae: Pathogenic
- Swine: Erysipelas
- Sheep & Cattle: Polyarthritis
- Chicken and Turkeys: Skin infections
- Humans: Skin infections, Erysipeloid; zoonotic pathogen
- E. tonsillarum: Nonpathogenic
2
Q
What is Erysipelothrix rhusiopathiae?
A
- Gram positive - May appear Gram negative
- Nonspore forming
- Facultatively anaerobic slender rods
- Alpha hemolysis
- H2S production along stab line of TSI Agar
3
Q
What is the habitat of E. rhusiopathiae?
A
- Prmary reservoir is swine
- Present in sewage or ground contaminated with feces
- Common on fish skin
- Does not survive too long in the environment
4
Q
What are the antigenic characteristics of E. rhusiopathiae?
A
- Peptidoglycan: Heat stable
- 26 serovars
- Serovars 1 & 2
5
Q
What is the mode of infection of E. rhusiopathiae?
A
- Ingestion
- Skin: scratches and wounds
6
Q
What are the Virulence factors of E. rhusiopathiae?
A
- Capsule: Acidic polysaccharide
- Surface proteins: Adhesins
- Hyaluronidase: Spreading factor
- Neuraminidase
- Type III hypersensitivity: Arthritis
7
Q
What is Neuraminidase?
A
- 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
8
Q
What is Erysipelas?
A
- 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
9
Q
What do the skin lesions of Erysipeals look like?
A
- 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
10
Q
What is the chronic form of Erysipelas result in?
A
- Polyarthritis
- Resembles rheumatoid arthritis in humans
- Endocarditis
- Valvular lesions resulting from bacterial emboli
11
Q
Does Erysipelas affect other animals?
A
- Sheep & Cattle - Polyarthritis
- Turkeys
- Males more often than females
- skin injuries
- Hemorrhagic lesions
12
Q
How is Erysipelas diagnosed?
A
- Clinical signs:
- Fever, arthritis, and skin lesions
- Bacteriologicl examination
- Recovery within 24 - 36 hours with penicillin
13
Q
How is Erysipelas treated and prevented?
A
- Penicillin, Tetracyclines, Lincosamides, and Tylosines
- Bacterin or modified live vaccine
- Vaccinated breeding stock to transfer protection to piglets
14
Q
What is Erysipeloid?
A
- Erysipelas in Humans
- 3 forms:
- Localized Cutaneous
- Generalized Cutaneous
- Septicemic
- Occupational disease - “Fish Handler’s Disease”
15
Q
What is Listeria?
A
- 8 species:
- L. monocytogenes
- L. ivanovii
- Disease is called “Listeriosis”
16
Q
What is Listeriosis?
A
- Primarily a disease of cattle, sheep, and goats
- CNS infection, Septicemia, abortion, and mastitis
- Food borne infection that causes high mortality
17
Q
What is Listeria monocytogenes?
A
- 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
18
Q
What is Listeria ivanovii?
A
- Less pathogenic
- No CNS infection
- Disease only in cattle
19
Q
What are the antigenic characteristics of Listeria?
A
- 13 serotypes
- Serotypes:
- 4b, 1/2a, 1/2b, 3 - Animals
- 4b, 1/2a, 1/2b, 1/2c - Humans (95%)
- Somatic (peptidoglycan) and Flagellar antigens
20
Q
What is the habitat of Listeria?
A
- Widely distributed
- Feces
- Tissues - Tonsils and lymph nodes
- Soil, Water, and vegetation
- Hardy and persistent
21
Q
What is the mode of infection of Listeria?
A
- 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
22
Q
What are the virulence factors of Listeria?
A
- 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
23
Q
What is Listeriosis in Ruminants?
A
- Infrequent but a serious disease
- Four Forms:
- CNS infection
- Abortion
- Septicemia or visceral
- Mastitis
- Rarely, Gastroenteritis, Keratoconjunctivitis
24
Q
What is the CNS Form of Listeriosis in Ruminants?
A
- Incubation period: 3 - 4 weeks
- Meningoencephalitis (adult)
- Meningitis (preruminant calves)
- Circuling disease
- Common in winter or early spring (silage)
25
What is the pathogenesis of CNS Listeriosis in Ruminants?
* Poorly understood
* No septicemia
* Bacteria travel through nerves
* Trigeminal nerve from the oral cavity
26
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
27
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
28
What is the Abortion form of *Listeriosis?*
* Late in gestation
* Sporadc in cows
* Outbreaks more common in sheep and goats
* Placentitis
* No other signs
29
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
30
What is Mastitis?
* Source: Feces
* Subclinical to clinical
* Suppurative infection
* *Listeria* in milk
31
What are the other forms of Listeriosis?
* Gastroenteritis with diarrhea
* sometimes with blood
* Keratconjunctivitis - Direct entry
32
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
33
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
34
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
35
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
36
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
37
What is *Listeria ivanovii?*
* Gram Positive rods
* Non spore forming
* Also hymolytic
* Causes abortion in sheep
* Rarely causes human infection
38
What are the top 5 pathogens causing Food Borne Illnesses?
1. Noro virus
2. *Salmonella*
3. *Clostridium perfringens*
4. *Campylobacter sp.*
5. *Staphylococcus aureus*
39
What are the top 5 pathogens causing food borne illnesses resulting in hospitalization?
1. *salmonella*
2. Noro Virus
3. *Campylobacter sp*
4. *Toxoplsma gondii*
5. *E. coli* O157
40
What are the top 5 pathogens causing food borne illnesses resulting in death?
1. *Salmonella*
2. *TOxoplasa gondii*
3. *Listeria monocytogenes*
4. Noro virus
5. *Camplylobacter*
