Rabies

T/F rabies is basically 100% fatal?

True

T/F rabies is 100% preventable?

True

Where is rabies most prevalent?

In rural and poor areas of the world

What is the major rabies-related virus?

Lysaviruses like Civettictis civetta and Felis catus

What genus if rabies virus?

Lyssavirus

What is the genome of rabies?

ssRNA negative

What protein gives rabies the bullet shape?

M protein

What protein in rabies produces a vaccine response?

G protein

Describe the infection and replication of rabies

Absorption
Viral RNP into cytoplasm
Transcription (viral polymerase transcribes mRNA)
Translation and processing
Replication
Assembly (M protein encapsulates RNP core and binds to glycoprotein in membrane)
Budding

What is the pathogenesis of rabies?

Highly neurotropic (no viremia)

Travels through nerves to spinal cord and brain (no clinical signs)

Virus rapidly multiplies in brain and moves to the salivary glands (signs of disease begins)

When does shedding of rabies begin in dogs, cats, and ferrets?

A few days prior to onset of clinical signs

What should you do if you are bit by an animal and are unsure on its rabies status?

Isolate for 10 days. If no clinical signs appear than the animal could not have been shedding yet.

Where does rabies remain in the brain?

Lowest and most primitive part, medulla oblongata

What does damage from rabies cause?

Activation of salivary glands and damage to breathing as well as loss of muscle control

What are the different rabies cycles?

Wildlife reservoir and canine reservoir that can transmite to domestic animals, livestock, or humans

What are the most commonly reported rabid domestic animal?

Cats

Why are cats more likely to develop rabies?

Less likely to be vaccinated
Roam outdoors unsupervised
Greater contact with wildlife
Wide variation in state vaccination requirements

How is rabies transmitted?

Bite with transdermal inoculation or scratches

Aerosol inhalation (usually in a lab or bat roost environment)

Human-human transplant (cornea, whole organ) all innervated tissues potential infections

T/F there is fomite transmision for rabies?

False

What is the immune response to rabies?

RABV tropism for nervous tissue which is immune pirviledged

Innate response causes early suppression of interferon response

Adaptive response develops in periphery and G protein elicits a robust B cell response. Occurs late in infection

What influences susceptibility to rabies disease?

Severity of exposure (deeper and bigger wound is more severe)

Viral inoculum

Location of exposure (higher risk near the head)

Variant

What are the two manifestations of rabies?

Furious rabies

Paralytic rabies

What does furious rabies look like?

Cerebral symptoms
Aggression with tendency to attack (70% of human cases)

What does paralytic rabies look like?

Spinal cord symptoms
Progressive paralysis
30% of human cases

What is the prodromal phase of rabies?

Subtle change in behavior
Slight rise in temperature
Dilation of pupils
Impaired corneal reflexes

What is the acute excitement neurologic stage?

Hyperactivity
Aggressive
Pharyngeal spasms
Muscular spams
Increased salivation

What are the general strategies for rabies control?

Surveillance
Animal vaccination
Legislation
Reservoir host population control
Human vaccination
Awareness

What is the purpose of rabies surveillance in animals?

Inform and facilitate rabies prevention and control measures and fulfill notification requirements

What is the national rabies surveillance system?

A laboratory based surveillance system with 130ish labs that conduct rabies testing

What monitors the country for wildlife rabies?

USDA wildlife services

How many animals rabies cases are reported to the CDC every year?

5,000

How many people get PEP for rabies every year?

55,000

What is the average cost of PEP?

$3800

T/F Species-specific variants of RABV transmit among animals in the same species but spill over to other species is rare?

True

What is a major concern for RABV?

The normal host can shift into a novel species requiring subsequent need for management intervention in other species

How many cases of human rabies occur a year in the US?

1-3 cases, usually from bats

What is the main reason why humans did not get PEP for rabies?

Not knowing bats can transmit rabies

How can we control rabies in reservoir animals?

Sterilization of dogs and population reduction (vampire bats)

Describe the rabies regulations in Kansas

Not State-level, but many counties require rabies vaccinations

What is the rabies vaccination schedule for domestic animals?

>3 months old
2 months old for some cats
Booster one year later then annually or triennially

What do rabies vaccines protect against?

Terrestrial and bat rabies

What wild animals get vaccinated by state/federal agencies?

Racoons, coyotes, gray foxes

What is the guidelines for PEP in vaccinated animals?

Immediately boosted within 4 days and observe for 45 days

What is the guidelines for PEP in unvaccinated aniamls?

All domestic species: euthanize
Dog and cat: vaccine in 4 days and quarantine for 4-6 months if vaccine is delayed
Livestock: quarantine for 6 months

What is the PEP for animals with a vaccine that is out of date and has documentation?

Dog and cat: booster within 4 days and observe for 45 days or more if booster is delayed

What is PEP for out of date vaccinated animals wit no paperwork?

Prospective serological monitoring or treatment or treat as unvaccinated

What is required for dogs that are rabies free or from low-risk countries to be imported?

CDC dog import form
Health on arrival
6 months or older
Microchip identifies

What is required to import dogs from a high-risk country?

Same as low-risk but also a certificate of US issued rabies vaccination or a USDA-endorsed export health certificate and a CDC dog import permit

What are the import requirements for dogs from a high-risk country and are foreign vaccinated?

Same as low-risk plus

• Certification of foreign rabies vaccination

• Valid rabies serology titer report from a CDC approved laboratory

• CDC dog import permit

• Reservation at CDC approved animal care facility

What are the vaccination requirements for travel?

Dogs vaccinated for the first time must wait 4 weeks

Puppies must be > 3 months old

Adult dogs may travel < 4 weeks after a booster if vaccinated after 3 months old and a have a current booster

What type of risk assessment should you do for rabies exposure in humans?

Species of offending animals

• Reservoir species

• Domestic or wild

What is the riskiest animal exposure for humans?

Bats

What should you do before doing PEP if you might’ve been exposed to a dog, cat, or ferret?

10 day observation period

What % of animals tested for rabies are rabid?

6%

Who should get pre-exposure vaccination in humans?

Persons with high frequency or continous risk of rabies exposures

Travelers to endemic areas

What are the steps to PEP in humans?

1. Immediate flushing

2. Passive immunization

3. Active immunization

The the whole PEP chart in humans

OK

What is the recommended treatment for a category 1 exposure of rabies?

None

What is the recommended treatment for a category II exposure to rabies?

Administer vaccine immediately

What is the recommended treatment for a category III exposure to rabies?

Administer RIG and vaccine immediately

Exposure to abt is what type of exposure?

Category 3

T/F you should give the full course + RIG for IC individuals even if previously vaccinated?

True

Why is canine rabies still a threat?

Neglected
Misunderstood
Inaccessible biologics
Funding for prevention measures not sustained

What should you do if an unvaccinated dog bites and kills a positive skunk?

Euthanize or vaccinate and strict quarantine for 4 months

What should you do if a dog that is currently vaccinated bites and kills a positive skunk?

Booster and observe under owner control for 45 days

What should you do if a dog that is vaccinated, but out of date bites and kills a positive skunk?

Treat as unvaccinated and do prospective serum monitoring (no anamnestic response then treat as unvaccinated)

What is prospective serologic monitoring?

Taking serum and administering rabies vaccine to see what happens to the serum and if the animal responded to the booster

What is the average incubation period for rabies?

35 days

T/F you can administer Ab to people that are exposed to rabies and that will provide immunity for 21 days?

True

When does the window for prophylaxis end?

When clinical signs begin

What are the 3 phases of disease manifestation for rabies?

Prodromal phase

Acute neurologic phase (excitement)

Acute neurologic phase (paralysis)

Coma or death

What does the acute neurologic paralytic phase look like for rabies?

Ascending myelitis
Flaccid paralysis
Muscle fasciculations
Paralysis of respiratory muscles

What are the clinical signs of rabies in dogs and cats?

Lethargy, fever, vomiting, anorexia, salivation, bone in throat, change in behavior, biting, self mutilation, irritability, seizures, paralysis, lack of muscle coordination

What are the clinical signs of rabies in cattle?

Profuse salivation, frequent bellowing, muscle spasms and tremors, constipation and tenesmus, foreign body in throat, ataxia and paresis, hind limb paralysis, recumbence

What are the clinical signs of rabies in goats?

Aggression (butting), circling and other repetitive actions, excessive bleating

What are the clinical signs of rabies in sheep?

Head pressing, vigorous wool pulling, sudden falling

What are the clinical signs of rabies in horses?

Distress or agitation, self mutilation, dropping lower jaw, lameness

What are the clinical signs of rabies in pigs?

Rapid chewing movements, head rubbing and rooting, muscle spasms and tremors, inability to squeal

What is required from the specimen information wise for rabies testing?

Type of animal
Location of animal
Animal vaccination status
Clinical status of animal

What sample can you send for rabies testing?

Whole carcass, head, or brain to get the brain stem and cerebellum

What is the gold standard for rabies testing?

Direct fluorescent antibody test (DFA) then validated and confirmed with conjugated antibodies against viral antigen

What does an apple-green color on a rabies test mean?

Positive for rabies

What samples can be collected for rabies antemortem testing?

Saliva, serum, CSF, and skin biopsies

What tests are used for rabies testing in humans?

RFFIT
RT-PCR
DFA

T/F you need to do several tests to detect in humans?

True

T/F a negative rabies test cannot rule out rabies in humans?

True