Lecture 34 11/14/24

Question 1

What are the stages of rabies clinical signs in dogs?

Answer 1

-prodrome/non-specific period
-excitative/”furious” phase
-paralytic/”dumb form” phase

Question 2

How long does the clinical course of rabies last?

Answer 2

less than 10 days

Question 3

What are the clinical signs of rabies in cattle?

Answer 3

-posterior incoordination
-anorexia
-repeated bellowing
-recumbency
-opisthotonos
-excessive salivation/difficulty swallowing
-running movements with front legs

Question 4

What are the clinical signs of rabies in horses?

Answer 4

-similar to cattle
-fasciculations of muscles around muzzle

Question 5

What are the signs of rabies in wildlife species?

Answer 5

skunks: out during daytime, unafraid
raccoons: aggressive nature, urbanized
foxes: out during daytime, unafraid
ferrets: ataxia, leg weakness, paresis/paralysis

Question 6

What are the clinical signs of rabies in humans?

Answer 6

-initial flu-like symptoms
-hallucinations
-confusion
-aggravation
-behavioral change
-coma

Question 7

What are the characteristics of the fluorescent antibody test of brain tissue?

Answer 7

-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

Question 8

What are the characteristics of the rabies skin test?

Answer 8

-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

Question 9

What are the characteristics of the direct rabies immunohistochemical test?

Answer 9

-can be done on frozen tissue
-does not require special microscope with UV light

Question 10

What are the characteristics of rabies PCR?

Answer 10

-high sensitivity and specificity
-can be performed on fresh, frozen, archived, deteriorated, and formalin-fixed tissue

Question 11

What are the characteristics of rabies prevention in humans?

Answer 11

-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

Question 12

What are the characteristics of rabies post-exposure treatment?

Answer 12

-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

Question 13

What are the methods for preventing rabies?

Answer 13

-vaccinate dogs, cats, ferrets, and livestock
-use the USDA-APHIS oral rabies vaccine program
-recognize “abnormal” behavior in animals
-reduce exposure to wildlife species

Question 14

What are the characteristics of rabies vaccines for animals in the US?

Answer 14

-no MLV for animals
-inactivated vaccine for domestic animals
-recombinant oral vaccine for wildlife

Question 15

What is the vaccine series for rabies in dogs and cats?

Answer 15

-initial vaccine given at 3 months of age or older
-initial vaccine boosted 1 year later
-subsequent boosters given every 3 years

Question 16

What is the vaccine series for rabies in ferrets?

Answer 16

-initial vaccine
-boosters repeated every year

Question 17

When is an animal considered vaccinated for rabies?

Answer 17

-28 days after initial vaccine
-when boostered if most recent vx is out of date

Question 18

What is the best post-exposure treatment for domestic animals?

Answer 18

rabies vaccine plus monoclonal antibody

Question 19

Why is it important to vaccinate livestock against rabies?

Answer 19

-valuable animals
-frequent human contact
-potential for crossing state lines regularly

Question 20

What is the goal of the USDA-APHIS oral rabies vaccine program?

Answer 20

stop western and northern spread of raccoon variant rabies

Question 21

What are the characteristics of the oral rabies vaccine?

Answer 21

-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

Question 22

How can interactions with wildlife be prevented?

Answer 22

-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

Question 23

What constitutes a rabies exposure?

Answer 23

-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

Question 24

What happens if a dog, cat, or ferret is exposed to rabies?

Answer 24

-immediate booster and 45 day observation if currently vaccinated or overdue
-euthanasia OR 4 month isolation and vaccination if never vaccinated

Question 25

What are the options for managing a dog, cat, or ferret that bites a person?

Answer 25

-euthanize and test before clinical signs
-10 day quarantine; euthanize and test if clinical signs develop

Question 26

What are the additional responsibilities of a veterinarian in the management of rabies?

Answer 26

-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

Question 27

How are rabies test samples prepped and shipped?

Answer 27

-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