Pm

• Rabies

  Acute viral disease of CNS
• Rabies

  • Affects all mammals
  • Caused by RNA virus→ Lassavirus→ Rhabdovirus
• Rabies epidemiology

  • Worldwide distribution (Australia, Antarctica)
  • Urban rabies: dogs, cats
  • Sylvatic rabies: foxes, wolves, bats
• Rabies transmission

  • Bite
  • Aerosol
  • Ingestion
  • Transplantation
• Rabies importance

  Neurological disease of mammals that is almost invariably fatal once clinical signs develop
• Rabies transmission

  Readily transmitted between mammals, whether same or different species, usually spread in saliva when infected animal bites another
• Rabies virus dissemination

  Enters eclipse phase after infection, replicates in non-nervous tissue like muscle, does not stimulate immune response but susceptible to neutralization if antibodies present
• Rabies incubation period

  Varies with amount of virus, virus strain, site of inoculation, host immunity, nature of wound; 10 days to 6 months, most cases 2 weeks to 3 months
• Rabies clinical signs

  • Initial signs nonspecific (apprehension, restlessness, anorexia, vomiting, fever, pupil dilation, hypersalivation)
  • Paralytic ("dumb") form: progressive paralysis, throat/jaw paralysis, profuse salivation, ataxia, incoordination, ascending spinal paresis
• Rabies post-mortem lesions

  No characteristic gross lesions, stomach may contain abnormal objects, histological signs of polioencephalo-myelitis and craniospinal ganglionitis, Negri bodies may be seen