161. Lyme borreliosis (Zoon.) and rabbit syphilis.

Question 1

Occurrence and Aetiology of Lyme borreliosis?

Answer 1

Occurrence

• Widespread infection (agent)
• Clinical form is rare in animals
• Frequent in humans (Zoonosis = Campylobacter > Salmonella > Borrelia)

Aetiology:

• B. burgdorferi, B. afzelii, B. garinii, and other species
• Geographical differences: all three species are present in Europe
• Cultured only in special media difficult

Question 2

Epidemiology of Lyme Borreliosis?

Answer 2

ͻ Epidemiology

• Susceptibility: human > companion animals (dogs, horses), farm animals, wild living animals
• Natural hosts vector: focal infection
• Natural host: rodents (mice) small mammals, wild living ruminants, birds nesting on the ground
• Vector (seasonality):
• Ticks (Europe: Ixodes ricinus)
• Trans-stadial passage, transovarial: rare
• Infection rate Hungary 2.3-11%
• Dog: brings closer the infection ʹ can carry and ticks pass to humans
• Regional differences in the infection rate of ticks (still quite high)

Question 3

Pathogenesis of Lyme Borreliosis?

Answer 3

Pathogenesis

• Infection: Tick
• Before blood sucking: present in the gut ʹ sucks blood infects
• Remove tick ASAP to decrease risk of infection
• Delayed inflammatory reaction
• (tick saliva contains anti-inflammatory materials & have anticoagulant effect)
• After blood sucking: reverse flow of blood from the tick to the human ʹ infects the host
• Changed surface antigen in the host (host not recognise them), anti-complementary
• skin -> Lymph -> blood(bacteremia) organs, skin, joint, brain, nervous system, eye
• Wide variety of clinical signs - Focus on skin, LNs & joints!
• Bacteria & Abs present at the same time ->Immune complexes deposited in eye/kidney –>lesions

Question 4

Clinical signs of Lyme Borreliosis?

Answer 4

Clinical signs

• Frequently subclinical or mild clinicalsigns
• Incubation 1-4 weeks
• Dog:
• Fever, depression, anorexia, listlessness, erythema (early sign), arthritis (large joints ʹ
• inflammation of different joints at different times b/c bacteria is limited in the blood)
• Chronic polyarthritis, lymphadenopathy, muscle paralysis, myocarditis
• Corneal opacity
• Renal failure (uraemia, protein-losing nephropathy, oedema)
• Cat: rare, mild, corneal opacity (seroconversion absent)
• Horse: arthritis, iridocyclitis (rare, similar to Leptospira iridocyclitis), ulcerative keratitis, nephritis,
• hepatitis, encephalitis, abortion, hyperaesthesia
• Ruminants: rare, arthritis, mainly seroconversion
• Human:
• Acute: fever, depression, headache, muscular pain, erythema (erythema chronica nigrans ʹ
• seems like the erythema is moving), enlargement of LNs
• Chronic: arthritis, meningoencephalitis, carditis, acrodermatitis
• No deaths ʹ No PM lesions!

Question 5

Diagnosis of Lyme Borreliosis?

Answer 5

Diagnosis

• Epidemiology (anamnesis ʹ tick bite) ʹ clinical signs (often none/not clear)
• Laboratory examination - difficult: low number of the agent
• Detection of the agent: microscope (sample from edge of erythema, see movement of bacteria), IF, PCR,
• culture (not routine diagnostic method)
• Detection of antibodies (most important): iIF, ELISA (v. sensitive, sometimes not specific enough ʹ used for
• first screening),
• Western-blot (to confirm the diagnosis, sensitive & more specific), paired samples

Question 6

Treatment of lyme Borreliosis?

Answer 6

Treatment

• Penicillin, ampicillin, amoxicillin, doxycycline, tetracycline, chloramphenicol
• Early treatment is necessary; Long treatment (~ 4 weeks)
• Symptomatic treatment

Prevention, control

• Tick control, removal of ticks, repellents (dog-collar/spot-on)
• Vaccines - dogs
• 1. Inactivated B. burgdorferi (cross protection btwn the agents)
• 2. Inactivated B. burgdorferi, B. afzelii, B. garinii
• 3. B. burgdorferi outer membrane proteins, recombinant
• ~ 1 year long protection
• 9-12 weeks then 3 weeks later –>booster

Question 7

Rabbit syphlis?

Answer 7

Occurrence:

• worldwide, rare (sporadic)

Aetiology:

• T. paraluiscunniculi(trepenoma) - cannot be cultured
• Genetic relationship with T pallidum

Epidemiology

Infection:

• sexual transmission,
• milk, during birth (mother to offspring)
• Indirect infection (devices)
• Slow spreading (Bacterium doesn’t rep fast

Question 8

Pathogenesis Rabbit Syphilis?

Answer 8

Pathogenesis

• Infection (sexual, PO) - asymptomatic infection can happen
• Mucous membranes of the genitals:
• hyperaemia, oedema, papules, ulcer, crust
• Bacteriaemia is rare, if then generalised
• Lesions of other mucous membranes, skin, nose, eyelid, oral cavity
• Sometimes myelitis (third phase of disease ʹ gets into CNS
• inflam. of SC), lame

Question 9

Clinical signs of Rabbit syphlis?

Answer 9

Clinical signs

• Incubation: 1 week- 4 months
• Genital mucous membranes: oedema, nodule, ulcer
• Generalisation: head, lips, nose, eyelids
• Nervous system: inflammation of the spinal cord (myelitis), paralysis

Question 10

Diagnosis Treatment and Prevention rabbit syphilis?

Answer 10

Diagnosis

• Epidemiology - clinical signs
• Detection of the agent: microscopy, silver impregnation, PCR
• Detection of the antibodies: RPR (Rapid plasma antigen) test!

Treatment: antibiotics (s.c.) penicillin and hay

Prevention

• Movement restrictions
• Disinfection (cages)
• Antibiotic treatment of contact animals
• Stop breeding