RABIES

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RABIES !

• WORLD RABIES DAY, SEPTEMBER 8, 2007
• Working together to stop the ongoing tragedy of
  rabies!
• Did you know....
• Rabies is 100 preventable, yet results in over
  55,000 human deaths each year.
• Rabies is present throughout the world.
• The greatest number of human deaths occur in Asia
  and Africa where canine (dog) rabies is common

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Rabies, Geography, Raccoons, Vampire Bats, and War

• What does Rabies cause?
• A few case histories
• Rabies in a Red Fox in Texas
• Rabies in a Fox in Arizona
• An Otter in Massachusetts?
• Bats in Ecuador
• Edgar Allen Poe revisited

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Typical Case in Humans

• A 49 year old man visited a neurologist with
  increasing right arm pain and seeming paralysis.
  The neurologist diagnosed neuropathy. The
  symptoms increased and with hand spasms and
  sweating. After developing dysphagia,
  hypersalivation, agitation, and generalized
  muscle twitching, the patient was admitted to a
  hospital. Within hours he became confused. The
  neurologist suspected rabies. Rabies immune
  globulin, vaccine, and acyclovir were
  administered.
• In addition, renal failure developed.
• The patient died.
• The patient did not report contact with a bat,
  although his wife reported that 3 months
  previously a bat had flown into their house and
  the patient had removed it.

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Typical Case in Humans

• Symptoms
• dysphagia, hypersalivation, agitation,
  generalized muscle twitching, confusion,
  delerium, coma, death
• Dyspahgia inability to swallow
• The old term hydrophobie

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Arizona Department of Health Services Office of
Infectious Disease ServicesVector Borne and
Zoonotic Disease Section Rabies in Arizona


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Rabies in Arizona
Pima County, 2005
Periodic skunk epizootic outbreaks of rabies in
Pima County
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Rabies Pathogenic Pathway

• Bite / break in skin
• ? local muscle tissue -Virus Replication
• ? virus enters peripheral nerve ending
• ? virus travels via retrograde axonal
  transport (50 mm/day) to
• CNS
• medulla ? midbrain ? hippocampus
• ? virus travels via angteriograde axonal
  transport to tissues, including
• salivary gland

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Rabies Pathogenic Pathway

• No signs of infection occur until the virus
  enters the brain, when..

• 1) Change in behavior leading - in carnivores -
  to wandering, and unprovoked aggression
• 2) Virus travels to the salivary gland
• leading to spread of the virus by biting
• 3) The brain infection leads to encephalitis
  and death

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Diagnosis of Rabies

• Performed via a Post-mortem autopsy on animals
• Observing neuronal brain cells with
  intracytoplasmic inclusions (Negri bodies)
• Identification of Rabies Strain

Negri Bodies
Rabid brain stained with Fluorescent anti-rabies
antibody
Rabid brain stained with Hematoxylin and eosin
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Why is there such a high risk of Rabies?

• Viral infection from bite of a furious rabid
  animal will be fatal
• Since virus travels from the
• bite to the brain, via nerves there is a
  variable latent period, making rabies
  unpredictable

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Rabies the virus
An enveloped ssRNA bullet shaped virus that
exists in the CNS of animals NOT environmentally
stable Bats can be persistently infected and
shed the virus in saliva.
The enveloped particle with spikes
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Rabies the virus
Rabies is a Lyssavirus in the family
Rhabdoviridae Lyssaviruses Australian Bat
Lyssavirus European Bat Lyssavirus -1 European
Bat Lyssavirus -2 Duvenhage virus Mokola
virus Lagos Bat virus Rabies virus
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The Niche of Rabies
Humans
Domestic Animal Reservoir (dogs and cats)
Wildlife Reservoir
Death (except for bats)
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The Rise of Rabies in Wildlife
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Where is Rabies in the USA?
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U.S. Animal Reservoirs of Rabies
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U.S. Animal Reservoirs of RabiesRaccoon Rabies
on the East Coast
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Raccoon Rabies on the East Coast
The virus has now jumped the St. Lawrence
seaway to Canada and the Appalachia mountains
to Ohio
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TypingRabiesVirus
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Why Type a Rabies virus?

• Where did the virus come from?
• The case of Rabies at the National Western
  Stockshow, Denver, in 1991
• A prize bull gets rabies
• Who and how many were exposed?
• From what source?

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Why Type a Rabies virus?
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Prevention of Rabies
Interrupting the ecological niche bat can we
control wildlife? Practical methods Avoidance,
quarantine, vaccination, wild or domestic
population control
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Prevention of RabiesThe vaccine
Pet Animal vaccines Wildlife edible bait vaccines
Euthanize (kill) all rabid animals Quarantine
biting, aggressive unvaccinated pets or pet
animals bitten by wildlife
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Prevention of RabiesThe Oral Vaccine

• The Oral Rabies Vaccine Program for Wildlife
• A vector vaccine
• A pan tropic harmless virus with the rabies
  immunogen (glycoprotein) gene added to it.
• Vaccinia Virus ( the Smallpox vaccine for
  humans)
• Virus in animal bait

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The Texas ORVP
                               1.  The bait
matrix is composed of either fish meal (Coyote
ORVP) or dog food (Gray Fox ORVP),
                  2.  A low-temperature sealing
wax is used to hold a vaccine sachet inside the
bait.                   3.  The vaccine sachet
contains 2 ml of oral rabies vaccine
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The Texas ORVP
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The Texas ORVP
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RABIES !

• WORLD RABIES DAY, SEPTEMBER 8, 2007
• Working together to stop the ongoing tragedy of
  rabies
• Future Eradication ?