RABIES

 

Etiology:

  1. Rhabdovirus that is transmitted by saliva after animal bite and less commonly by aerosol.
     
  2. Animals most involved are skunks > bats > raccoons > foxes=dogs=cats. Rodents are not involved.
     
  3. Virus spreads along the axon to CNS and then to periphery.

S & S:

  1. Patients evaluated immediately after the bite are asymptomatic.  Early symptoms are nonspecific and include: fever, headache, malaise, anorexia, pruritus and paresthesias.  Late symptoms include agitation, hydrophobia, confusion and paralysis.

Differential:

  1. Polio, tetanus, encephalitis, meningitis, alcohol withdrawal, Guillain-Barré, cholinergic poisoning.

Treatment:

  1. If animal is high risk and captured it is sacrificed, and pt is started on treatment until test results are back.
     
  2. If animal is low risk, pt has 48 hrs. before initiating the treatment.
     
  3. Common circumstance is a neighbor's dog that bit the pt. The pt has a choice of getting vaccination now or finding out within 48 hrs. if the animal was vaccinated.  Pt should be told that vaccination is not completely  protective.
     
  4. Wound is cleansed with soap and scrubbing (90% protective).
     
  5. Passive immunization: HRIG 20 IU/kg.  Half is given IM in gluteal area and other half is given locally around the wound.
     
  6. Active immunization: HDCV 1 cc in deltoid on days 0, 3, 7, 14, 28 from the day of the bite.  It takes 1-2 weeks to develop an antibody response.  If HRIG was not given initially, it could be given up to 1 week after getting HDCV.  Pt that had prior immunization should get HDCV only on days 0 and 3.
     
  7. Both immunizations are safe in pregnancy.  In immunocompromised pt, the proper response should be confirmed by titers.

[BACK]