Rabies and VSV Flashcards
what do you use to diagnose rabies?
rabies FA
what parts of the brain do you need to do a FA for rabies?
midbrain
cerebellum
hippocampus
what pathway do Lyssaviruses like rabies take to reach the central the central nervous system and how do they get back out? how does that explain the incubation period?
AChR at peripheral nerves -> ascending fibers -> spinal column -> CNS -> peripheral excretory organs (salivary glands)
how long are quarantine periods for an animal that has been bitten someone and an animal that has been bitten? what is the rationale for the length of quarantine?
-animal bites someone: 10 days (typical period of time between onset of symptoms and death)
-(unvaxed) animal is bitten: 4 months (max incubation period; ferrets=6months)
what are the pathology and pathognomonic microscopic findings in rabies infections? what tissues are most commonly tested, and by what assay?
perivascular cuffing in CNS with Negri bodies
intracytoplasmic neuonral inclusions
-midbrain, cerebellum, hippocampus- FA on impression smears
what vectors are responsible for rabies transmission in man and animals and what roles do they play both in the US and worldwide?
US- bats +/- skunks, raccoons
outside of US- dogs
how is rabies most commonly diagnosed- which tissues are needed and what it is the testing methodology?
fluorescent antibody testing of the brain (cerebrum, midbrain, cerebellum)
what lyssavrius are located in Europe and Australia?
bat lyssaviruses
what is the central phase of the rabies pathogenesis and where so they travel from?
retrograde axonal transport to dorsal ganglion
-salivary glands, eye, skin
what are the progressive neurological signs of rabies in dairy cattle?
stargazing
ataxia
what is the diagnoses in animals that bite
euthanasia
10 days isolation to monitor
prevention and treatment for vaccinated animals?
post-exposure in animals (animals that have been bitten)
what is the prevention and treatment in non-vaccinated animals?
-euthanize if the biting animal tests positive
-rare, long-term inpatient monitor (4months) if the biting animal was not tested, followed by vax
-ferrets 6 months
how is VSV transmitted and how does that help explain its cyclical appearance?
Culicoides midges which are only present seasonally
large parts of the country are exposed and develop a herd-level immunity for 5+years
what are important differentials fro VSV infections?
any of the vesicular diseases- FMD, SVD, VES, etc
which species are affected by VSV? How might that help you differentiate it from the many important differentials?
VSV affects most livestock, including horses
vesicular lesions in horses and other species almost always mean VSV
what procedures must you take when VSV is suspected and where are samples sent for diagnosis?
notify state/regional USDA veterinarian
samples sent to USDA labs in either Iowa or Plum Island
what are the clinical signs of vesicular stomatitis?
vesicular lesions
hypersalivation
coronary band lesion
how is vesicular stomatitis virus transmitted?
direct contact
Culicoides spp
what is the treatment and prevention for vesicular stomatitis virus?
palliative
no commercial vax
quarantine (14-30 days)
insect management
