How does polyomyelitis work?
Its an enterovirus (Type 1, 2, 3) that infects anterior horn cells of LMNs causing Asymmetric Flaccid paralysis (mainly in legs)
What type of poliomyelitis is used in the vaccine?
Trick question its all 3
How does Rabies work?
transmitted by bite of saliva in open lesion
Neurotropic, so the virus gets into PNS and migrates to the CNS
- Paraesthesia at site of lesion
- Asc. Paralysis
How do we diagnose Rabies?
PCR or Serology
These only work after the clinical disease is already apparant
How does the rabies vaccine work and who gets it in the UK?
Active immunisation using the killed virus.
- Bat Handlers
- Handlers of imported animals
- Travellers to enzootic areas
How do we treat Rabies after exposure?
# Wash the wound # Give the Active Rabies Immunisation (Vaccine) # Give Passive Immunisation (Human Rabies Immunoglobulin) if at high risk
How does Tetanus work?
Clostridium Tetani (Anaerobic Gram +ve Baccilus)
Toxins block inhibition at NMJ causing rigidity and spasm
How do we prevent Tetanus?
Penicillin & Immunoglobulin for high risk patients after exposure
How does botulism work?
Clostridium Botulinum (Anaerobic Gram +ve Bacillus)
Neurotoxin binds irreversibly to presynaptic membranes of NMJ & Autonomic junctions,
This blocks Ach release and they wont recover till new axons sprout
How is Clostridium Botulinum transmitted to humans?
- Infantile intestinal colonisation
- Food Borne
- Wound (Injecting drugs mainly)
How does Botulism present?
4-14 days incubation then:
- Desc. Symmetrical Flaccid Paralysis
- Incl. Resp Failure
- Autonomic Dysfunction e.g. Pupil Dilation
How do we diagnose Botulism?
- Nerve Conduction Studies
- Culture from wound
- Mouse Neutralisation Bioassay (For toxin in blood)
How do we treat Botulism?
- Anti Toxin (A, B & E)
- Penicillin/Metronidazole (prolonged treatment)
- Radical Wound Debridement