Rabies Flashcards
Family
Rhabdoviridae
Structure
enveloped negative-sense ssRNA
Locations
found most places except Hawaii, Japan, and New Zealand
History
one of oldest viruses in known history
originated in old world bats
1st vaccine
Dr. Louis Pasteur-1885
Transmission Cycle
Direct transmission through bite
Rarely can be transmitted via ingestion of virus
Main reservoirs
East Coast: raccoon
Midwest/West Coast: Skunk
Arizona: fox and skunk
Alaska: fox
Pathogenesis
Saliva enters through the bite-> local muscle cells for ~2 days-> local nerves-> brain in 2-3 days can start infecting others
Fast or Slow progression
Slow progression- average is 3-8 wks but can take up to a years depending on location of bite and species
Clinical Signs Prodromal Stage
first 2-3 days after symptoms
-personality change, larynx spasms, active licking or scratching site of original bite
Clinical Signs Excitative stage
next 1-7 days
animal has no fear, suffers hallucinations, and becomes very aggressive
Clinical Signs- Paralytic or Dumb Stage
next 2-4 days
weakness/paralysis- larynx is paralyzed-> inability to swallow-> drooling or foaming at the mouth
Incubation
Dogs: 21-80 days
Cats: 28-42 days
Wildlife: 30-180 days
Pathologic Lesions
spongiform lesion in brain, brain appears swollen, congested, and inflamed, negri bodies in brain tissue
Diagnostics
ONLY test is to diagnose rabies is fluorescent antibody testing of brain
Can to bloodwork, PCR or others to rule out other diseases