Lecture 34 11/14/24 Flashcards
What are the stages of rabies clinical signs in dogs?
-prodrome/non-specific period
-excitative/”furious” phase
-paralytic/”dumb form” phase
How long does the clinical course of rabies last?
less than 10 days
What are the clinical signs of rabies in cattle?
-posterior incoordination
-anorexia
-repeated bellowing
-recumbency
-opisthotonos
-excessive salivation/difficulty swallowing
-running movements with front legs
What are the clinical signs of rabies in horses?
-similar to cattle
-fasciculations of muscles around muzzle
What are the signs of rabies in wildlife species?
skunks: out during daytime, unafraid
raccoons: aggressive nature, urbanized
foxes: out during daytime, unafraid
ferrets: ataxia, leg weakness, paresis/paralysis
What are the clinical signs of rabies in humans?
-initial flu-like symptoms
-hallucinations
-confusion
-aggravation
-behavioral change
-coma
What are the characteristics of the fluorescent antibody test of brain tissue?
-only test to rule out transmission of rabies where humans or animals are exposed
-must examine hippocampus, cerebellum, and medulla
-virus must be found in CNS in order to make it into saliva
-98% sensitivity
What are the characteristics of the rabies skin test?
-done on live animals
-fluorescent antibody that IDs rabies antigen
-muzzle biopsy of “guard hair” follicle
-positive test is valid
-negative test cannot rule out rabies
What are the characteristics of the direct rabies immunohistochemical test?
-can be done on frozen tissue
-does not require special microscope with UV light
What are the characteristics of rabies PCR?
-high sensitivity and specificity
-can be performed on fresh, frozen, archived, deteriorated, and formalin-fixed tissue
What are the characteristics of rabies prevention in humans?
-pre-exposure vx consists of 2 doses given on days 0 and 7
-individuals at greater risk of rabies exposure are advised to have titers checked and/or receive a booster dose within 3 years of initial vx
-check titers every 2 years
What are the characteristics of rabies post-exposure treatment?
-must be done before clinical signs appear
-if previously vaccinated, receive IM injections on days 0 and 3; no rabies immunoglobulin needed
-if not previously vaccinated, receive IM injections on days 0, 3, 7, and 14, as well as rabies immunoglobulin
-immunocompromised individuals also receive IM injections on day 28
What are the methods for preventing rabies?
-vaccinate dogs, cats, ferrets, and livestock
-use the USDA-APHIS oral rabies vaccine program
-recognize “abnormal” behavior in animals
-reduce exposure to wildlife species
What are the characteristics of rabies vaccines for animals in the US?
-no MLV for animals
-inactivated vaccine for domestic animals
-recombinant oral vaccine for wildlife
What is the vaccine series for rabies in dogs and cats?
-initial vaccine given at 3 months of age or older
-initial vaccine boosted 1 year later
-subsequent boosters given every 3 years
What is the vaccine series for rabies in ferrets?
-initial vaccine
-boosters repeated every year
When is an animal considered vaccinated for rabies?
-28 days after initial vaccine
-when boostered if most recent vx is out of date
What is the best post-exposure treatment for domestic animals?
rabies vaccine plus monoclonal antibody
Why is it important to vaccinate livestock against rabies?
-valuable animals
-frequent human contact
-potential for crossing state lines regularly
What is the goal of the USDA-APHIS oral rabies vaccine program?
stop western and northern spread of raccoon variant rabies
What are the characteristics of the oral rabies vaccine?
-recombinant
-licensed for free-range raccoons, grey foxes, and coyotes
-fish or dog food flavored bait
-not available to practicing veterinarians
-bait drops done for 2-3 weeks a year
-bait distributed via plane or by hand
How can interactions with wildlife be prevented?
-do not feed wildlife
-do not leave food outside for dogs or cats
-keep garbage locked up
-have bird feeders that are not accessible to other species
What constitutes a rabies exposure?
-bite or saliva contact with mucous membrane/skin break from a known or suspected rabid animal
-contact with mucous membrane/skin break from moist tissues of a dead known or suspected rabid animal
What happens if a dog, cat, or ferret is exposed to rabies?
-immediate booster and 45 day observation if currently vaccinated or overdue
-euthanasia OR 4 month isolation and vaccination if never vaccinated
What are the options for managing a dog, cat, or ferret that bites a person?
-euthanize and test before clinical signs
-10 day quarantine; euthanize and test if clinical signs develop
What are the additional responsibilities of a veterinarian in the management of rabies?
-proper handling of rabies specimens
-preventing exposure of self and staff
-ensuring that euthanized animals have not bitten anyone in last 10 days; written acknowledgement
How are rabies test samples prepped and shipped?
-delivered to rabies lab. within 48 hours
-fresh, unfixed brain
-brain should not be removed unless state requires it
-animal should NOT be fixed in formalin
