Spirochetes I (Borrelia) Flashcards
What are the general characteristics of Spirochetes?
- Long, slender, spiral-shaped
- Gram negative
- Tightly coiled and look like miniature springs or telephone cords
- Motile - axial filaments similar to flagella
- Extracellular organisms
How is the Membrane and Cell wall of Spirochetes different from regular Gram Negative bacteria?
How is the Membrane and Cell wall of Spirochetes different from regular Gram Negative bacteria?
How are Spirochetes Classified?
- Genus: Borrelia (8-16 mcm)
- vector-borne (tick and louse)
- 15-40 flagella
- Genus: Treponema (3-8 mcm)
- T. pallidum, transmitted by close contact
- Genus: Leptospira (6-20 mcm)
- Hooked end, pathogenic and free living
- 2 flagella
- Genus: Brachyspira
- 6-10 flagella
What is the Pathogenesis of Spirochetes?
- Extracellular pathogens
- Migrate from the site of infection to other parts of body via blood an lymph
- Antigenic variation
- important method to evade host response
How is a Spriochetes infection diagnosed?
- Clinical signs and case history
-
Microscopy
- Dark field
- Fluorescent antibody
- Giemsa or Wright’s stain
-
Antibody tests
- Western blot, ELISA
- Paired serum sample analysis
- acute and convalescent
- PCR
How is a Spirochetes infection treated?
- Doxycycline
- Drug of choice
- Penicillin
- Erythromycin
- Tetracycline
What are the important diseases are caused by Spirochetes?
- Vector-borne diseases
- Ticks
- lice
-
Lyme Disease
- Human, Dogs, Horses, Cattle, Cats
- Avian Borreliosis
- Relapsing Fever - Humans
What is the cause of Lyme Disease?
- Borrelia burgdorferi
- Transmitted by:
- Ixodes scapularis
- Ixodes pacificus
What are the signs and symptoms of Lyme Disease?
- Tick Bite
- Clinical symptoms start ~7 days in humans
- Fever
- Malaise
- Fatigue
- Stiff neck
- Headache
-
“Bull’s eye” Rash
- Erythema Migrans
- Pathogen disseminates from the site of tick bite via lymphatic and blood circulation
-
Arthritis:
- Intermittent swelling and joint pain
- Muscle pain and depression
-
Neurological manifestations
- Lymphocytic meningitis
- Cranial neuropathy
- Sleep disturbances
- RARELY fatal
What animals can B. burgdorferi cause infections in ?
- Humans
- Dogs
- Cats
- Cattle
- Horses
How does Lyme Disease affect Dogs?
- Loss of appetite and fever
- 104 - 105F
- Lethargy
- “shifting lameness”
- Kidney damage
- Heart disorders
- Neurological symptoms
- aggression
- Delirium
- Seizure
How does Lyme disease affect Cats?
- Fever
- Loss of appetite
- Fatigue
- May show lameness
- Eye infection
- irregular breathing
- Some infected cats maybe asymptomatic
How does Lyme Disease affect Cattle?
- Many do not show any visible clinical signs
- Fever
- Laminitis
- Weight Loss
- Lameness
- Swollen Joints
- Skin Rash may be present on the udder
- B. Burgdorgeri May be found in urine, colostrum, blood, milk, synovial fluid and in aborted fetal tissues
How des Lyme Disease affect Horses?
- Mild to no fever
- May have lameness or stiff joints
- Laminitis
- depression
- Loss of appetite
- Blindness or partial loss of vision
- Abortion
- Neurological signs
- Head tilt
- Aimless wandering
- encephalitis
- Transplacental transmission have been reported
- Newborn colts my display birth defects